Cliff's Quadrajet Parts and Rebuild Kits
Quadrajet Problem Solving => Diagnose a Quadrajet carburetor problem => Topic started by: MP81 on August 26, 2019, 08:29:29 AM
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So, I'm pretty sure most of what has been suggested to me thus far for this is probably the correct answer (that being: rebuild carb), but I figured I'd pose the question here just to be sure.
Earlier this year, I noticed that the car doesn't seem to like heavy throttle anymore (that said, this has happened on a few occasions of light throttle applications - I will detail below). If you get on it, it just doesn't go anywhere for a good few seconds - it's hard to describe exactly what it sounds/feels like, but it's almost like a rough/grating sound, mild sputtering (without actually sputtering). It just sounds "rough", and it just sits there not really accelerating, until it suddenly smooths out and pulls way harder (relative, given you were just not going anywhere the second before).
I'm sure not coincidentally, this seems to have also come at the same time as the vehicle starting to a rather low idle. The car starts (right up if it's been run in the last couple days, after the usual long cranking if it's been more than a few days - car has always been that way, probably the bowls draining or something) and idles at roughly 500 RPM, so you have to give it a rev or two to keep it from stalling. Those revs sound very "broken up". After a few seconds, it goes up to ~700 RPM where it should be, and sits there just fine.
Driving the car like a normal human being seems to be mostly fine, but as I've mentioned earlier in the post, sometimes you can notice it. One time that stands out in my mind was really the first instance where I noticed this all happening, leaving my spot after a car show back in June. Car started up right away, since I had driven it there in the morning, and then I went to pull out of the spot, but I looked like a total rookie with the car hopping up and down like it was trying to stall (4-speed car)...but I was driving it like I normally would, it's just that the gas I was giving it didn't seem to be doing anything at all. Then suddenly, that "smooth out" hit and the car took off, since now my foot was in it far more than normal, trying to get it to go.
I'm thinking maybe something to do with the accelerator pump, but I've really got no idea.
Made sense to post here before I go rebuilding the carb, in the event that maybe this is something else. For what it's worth, it did not do this at all last year, nor did I notice it the few times I started the car and let it run up to temp over the winter.
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I did some quick investigation yesterday:
First what I did was play with the throttle before even starting the car - last time it was started was a week or so ago, so the main bowl wasn't full. What I noticed were slight "fuel bubbles" coming from this kind of "crevice" here in the corner between the gasket and the raised area around the choke flap. You could hear it and see it "lightly" bubbling there when you'd open the throttle.
(http://nastyz28.com/attachments/p1130310-jpg.82243/)
(http://nastyz28.com/attachments/p1130313-jpg.82244/)
With the car running and the choke flap fully warmed up, it looked like I was getting a good solid spray in the primaries:
(http://nastyz28.com/attachments/p1130317-jpg.82245/)
After revving it, the car seemed to only want to idle at like 500-600 rpm, lower than it should be, but it stayed there and didn't stall, but it was a little odd.
I noticed that this rod was a bit wet where it goes into the carb body:
(http://nastyz28.com/attachments/p1130322-jpg.82246/)
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the "fuel bubbles" is normal with throttle movement. it should actually be a small stream, this is from your accellerator pump. the rod in the last picture is the stem from the accellerator pump. most likely time to order a kit from cliff and rebuild. make sure to check primary throttle shaft for wear (most likely) and also make sure primary & secondary well plugs are not leaking. you can check them with shop air and soap water.
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The fuel bubbling in here is normal? Didn't seem like the other side did that, but I could be wrong. I don't recall it doing that in the past, before all this started happening.
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it should be squirting fuel into the other side. sounds like airhorn gasket and/or the airhorn is warped slightly. cliffs airhorn gaskets are thicker than stock and generally allow for a slightly warped airhorn.
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It does - but yes, I was wondering if it was something like that.
Ultimately, necessary action aside, what is likely the root cause of the issue? It seems odd that it'd be too rich or too lean for a few seconds, and then suddenly be okay - but maybe it is! I'm an engineer, so I just like to know things, for my own personal knowledge.
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your accellerator pump seal is probably worn and failing from age and is probably not ethanol resistant.
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And then putting in too much fuel initially, causing it to bog, then when it stops adding fuel it goes back to being a better AFR which is where it actually accelerates?
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The "bubbling" at that location indicates a plugged hole in the partition past the accl pump discharge hole in the airhorn. You need to remove the carb, remove the top and clean it out.
While it's apart get one of our kits and replace all the internals to get it up to par for this new fuel. It looks like it's been a while since it's had any TLC anyhow.....Cliff
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It looks like it's been a while since it's had any TLC anyhow.....Cliff
If my assumptions are correct - 38 years! I have to confirm with my uncle, but I'm pretty sure this thing has never been off the car, haha.
Thanks for the feedback guys, looks like I will be placing an order here for the rebuild kit shortly!
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Those are actually excellent units, and after that many years for sure it needs a good cleaning and some modern components for this new fuel......Cliff
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Good deal! I just placed the order for the rebuild kit.
I also have the book (my buddy had a copy he let me borrow), but haven't had a chance to dive into it too much (we're on vacation this week) - but it looks like it's a pretty good breakdown on how to rebuild the whole carb. Does it mention any "performance tweaks" that are worth doing while I'm in there?
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Thanks for the order.
The CCC carburetors respond to all secondary performance mods same as any non-CCC unit.
The ECM only controls part throttle A/F, so heavy and full throttle is same as any other unit.
Always do the "basics", all throttle plates adjusted to 90 degrees, index the throttle plates if/as needed.
A quick release choke pull-off helps, and some will need a little material ground off the stop on the secondary air door to get a little more CFM to them........Cliff
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I assume all that is detailed in the book?
Do I need any fancy tools? I've seen that I need certain Thexton tool kits, but I've heard from others I don't? I totally forgot to order any, so "not" would be the preferable answer, haha.
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No special tools required. I like to slot the M/C solenoid adjustment screw with a fine hacksaw blade so I can turn it with a tiny flat tip screwdriver. Pretty easy to make a special tool for it was well from an old screwdriver. Cut a "slot" in the screwdriver shank pretty much like a tire valve core tool.
The upper metering rod limit screw can be done in similar fashion. I'd tap and install set screws instead of driving in the tamper proof plugs so any adjustments needed can be done with the carb on the engine......Cliff
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Sweet - sounds like stuff I can pick up at Home Depot as needed. I might actually have a couple set screws, somewhere...
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Hopefully you don't mind, but I'm going to document my progress here - in the event that I have an issue, or perhaps in case someone spots something I didn't!
Before removing the carb:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70141080_10156659072313597_3653558469153259520_n.jpg?_nc_cat=107&_nc_ht=scontent.fdet1-1.fna&oh=35f829ae098e7e5bf8db11e62171f02c&oe=5E05CB60)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69687416_10156659072098597_1508833010496045056_n.jpg?_nc_cat=110&_nc_ht=scontent.fdet1-1.fna&oh=6c2d23ccef0f854029b3cca1f3bff680&oe=5DF38534)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69988242_10156659072493597_8047901988303667200_n.jpg?_nc_cat=106&_nc_ht=scontent.fdet1-1.fna&oh=43c00ad7873b52caf84d8a7400d542ec&oe=5E145DDE)
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70978473_10156659072083597_2011857458489720832_n.jpg?_nc_cat=105&_nc_ht=scontent.fdet1-2.fna&oh=a93bfe9a997ffa8d8482a3937a2eee2d&oe=5DC823E9)
Carb removed - the inside of the intake looks pretty clean
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69874106_10156659072148597_2986854428121759744_n.jpg?_nc_cat=106&_nc_ht=scontent.fdet1-1.fna&oh=52bda04cc0341a9bba513fc1d2db2ca6&oe=5E12AC4D)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70633856_10156659072343597_6842072430844837888_n.jpg?_nc_cat=100&_nc_oc=AQm4w_tRGq54ZPG3DhrfhEBMXqYyAXFPUYYC2O20mtlv1xbZHY7vN63ZFHL01wDBEXQ&_nc_ht=scontent.fdet1-1.fna&oh=207ff9bbc80bb8bd4657f2a45305e784&oe=5E12634F)
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Carb off the car:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70747165_10156659072373597_3327340374283780096_n.jpg?_nc_cat=110&_nc_oc=AQlwTpug3StPwb8xyu9BOrraLtDUBEW0wSL-RuMUEy6UjyFEclkm2OF0JP8A0V_X4W8&_nc_ht=scontent.fdet1-1.fna&oh=e5edacd52e7b0abad61145a5dd8fa7bc&oe=5DF82F70)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69877234_10156659072568597_1629869350720634880_n.jpg?_nc_cat=110&_nc_oc=AQmPLKVWgdADfn09_DfEoiFkC_vFziPnAKveTUbB71A1hlnrR6oKToWI0tdaMfFbd_k&_nc_ht=scontent.fdet1-1.fna&oh=43f89cbaf0105efdb5f1858dd91ed449&oe=5E0D4384)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69683976_10156659072803597_2583468484046356480_n.jpg?_nc_cat=101&_nc_oc=AQmJ0VoWkuW7wCq5i8q9uqU42dKH8946f1f6_j8eAHOhWXW4Zvej59G7UJAuVuZfVIg&_nc_ht=scontent.fdet1-1.fna&oh=23201d3903640705d4a82b2b44fa52ef&oe=5E01141A)
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/69767431_10156659072693597_2940030187854626816_n.jpg?_nc_cat=109&_nc_oc=AQl-MNE04fgYEPTTq5QObVczYdCr5T_8XCwWmAvqgRP1A6-AOYJmAkQv9NOemPoGqU8&_nc_ht=scontent.fdet1-2.fna&oh=39de715fa2d748aa9e14287142f36ce0&oe=5DFC0322)
Fuel filter looks a tad dirty...
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69948298_10156659072518597_5411816087547281408_n.jpg?_nc_cat=100&_nc_oc=AQlN3ftjkbOnJQVgK1Bc1kIaqVzXUmj7BMkhN3V6ZBPusY9PNC4cJbptBT0MAtv2hgA&_nc_ht=scontent.fdet1-1.fna&oh=abc2ffd7166c90660466774e29e862a9&oe=5E1361BC)
After a quick spray/wipe off with carb and brake cleaner - quite a lot cleaner (especially for doing this outside while being eaten alive by mosquitoes)! Time to let this dry overnight...
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69856149_10156659072653597_3864905915639529472_n.jpg?_nc_cat=103&_nc_oc=AQl3Qg7N06Nt9Eg3SdXubAiWa_ZeJCDQpLTj90SJah0RTZEspZQPww9WgxzDNbHNvnU&_nc_ht=scontent.fdet1-1.fna&oh=fc68f25b0fce251aefd393569e1acbda&oe=5DF2E718)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69885569_10156659072713597_514002062279704576_n.jpg?_nc_cat=110&_nc_oc=AQkVOF-WKvdP5ZkZBrY9jU0RwdFETR2cHYl_keMnu-zF0G9602edV_lIzYgFA5lxpjo&_nc_ht=scontent.fdet1-1.fna&oh=0a92bc894b0bef6c0a41fec1e6d02efb&oe=5E0177E5)
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Looks like it's had some work done to it. The primary throttle shaft screws have been out at some point, hopefully it got bushings during that evolution......Cliff
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It must have. Someone was saying a plug up top wasn't there that should be if it was never rebuilt.
How can you tell on the screws? Would be great if the bushings were done so I don't have to...
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Also, I forgot to mention, all four bolts were not even finger tight. ;D
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Started disassembly:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/69673686_10156661190473597_719545813948170240_n.jpg?_nc_cat=105&_nc_oc=AQmOFrUMOsfwVu0EOAijxQIrAh7HrlaQoqap5-Zk8rrN9znr4t6ASSF-W_rZIVIqRws&_nc_ht=scontent.fdet1-2.fna&oh=2271b4b1d5b45c24579c0acc74c0f580&oe=5DF65D11)
Air horn removed:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69949806_10156661190328597_7749259361590968320_n.jpg?_nc_cat=103&_nc_oc=AQkfMisNyich-10u04BMrIloHDTb2tMuUlQclMck8wlz7tW9Nybyl0nTAnKtx5Ry-Dg&_nc_ht=scontent.fdet1-1.fna&oh=abfb7da65fda506ce30981435de9074a&oe=5E01FAC1)
Main casting with the air horn removed:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70293390_10156661190368597_5556962102133915648_n.jpg?_nc_cat=111&_nc_oc=AQlFsRBmJ-AH8JyizfzbBLp0JBBbZu6cJ8lq1LWW-AMd9kk16_LY1dAhw0xCnEr7zrA&_nc_ht=scontent.fdet1-2.fna&oh=76ff1eed4b596c83355dd781804d58f5&oe=5DEFB6C1)
Gasket removed:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70390280_10156661190483597_3649977553055121408_n.jpg?_nc_cat=109&_nc_oc=AQlOWlhsbFeBre-8pBzhaFqYjuxTXCaig9Xeu6qbysAD3Y2LoXnHY0FEadi-sGhgCc8&_nc_ht=scontent.fdet1-2.fna&oh=0e8faa381d8202b5ebe68d89d063f597&oe=5DF491C7)
Accelerator pump - seal does look mostly okay, I think:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69913794_10156661190313597_8992311098501758976_n.jpg?_nc_cat=106&_nc_oc=AQlohI76vCpT7mNh4jZFnL0hanM-NIt_S7KUlRGFeLniIQcFa4koyVmwAJyStpYdFP4&_nc_ht=scontent.fdet1-1.fna&oh=fc14560e599b49a8db76ca42a6ec986e&oe=5E0A174F)
Main casting components removed:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70127463_10156661189858597_3370062581480816640_n.jpg?_nc_cat=109&_nc_oc=AQk8jeXm2NM7ThSh5A32LVNhCqjtsKXj-AMCIu17yOHd_yYDo-BSKE0o-Yb5dat8ng4&_nc_ht=scontent.fdet1-2.fna&oh=d176b01f37cf87b2b263226d1ef8f08f&oe=5E1412FE)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69900877_10156661190178597_5660344172561825792_n.jpg?_nc_cat=106&_nc_oc=AQn7h9S_2ugSJEH2Tz8tbHCkynHTh2yccZAQqITXNVqZ_Mb8FCYJZQZgVYBB1eye6Gc&_nc_ht=scontent.fdet1-1.fna&oh=36b7464950c4c97b984e2c2c4b5e8642&oe=5DFDCB9C)
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Well, looks like the plugs were removed down here:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69024535_10156661189888597_2287660179266732032_n.jpg?_nc_cat=106&_nc_oc=AQmWm9LV0gviUmZ7KmM4R0vrPi3tHqEGiqkU_GwtMEmP6OSWYG7xjhh1rxhavrwnvBg&_nc_ht=scontent.fdet1-1.fna&oh=eea4cf71b88f32a6abd195e1caac3d91&oe=5DEF0071)
Throttle plate removed:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69957972_10156661190168597_3048594630246400000_n.jpg?_nc_cat=100&_nc_oc=AQk4nQYjCNePZFz1I_mhNnXq-AJuaziVN3hRy8O4r6ZPzUEU2mHoz2luaFZ_1iiNYkU&_nc_ht=scontent.fdet1-1.fna&oh=b4c4293348a07a4b40b0d6afd042cc79&oe=5DFAE883)
Fuel bowl plugs have already been epoxied in the past:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70263956_10156661190118597_7946553984322371584_n.jpg?_nc_cat=105&_nc_oc=AQkje-4asVoQ4mdRJlTAZZGUnSzDbeucEZwAJgwg76oES68vgQik6MACAO_J-RQhA54&_nc_ht=scontent.fdet1-2.fna&oh=e1594d8d225efef6b3ee2dc0e0005232&oe=5E0DF3DE)
Throttle plate gasket removed:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69784056_10156661189848597_2977891973836308480_n.jpg?_nc_cat=110&_nc_oc=AQlH4drB-CPhptx-C46zIph8_pL2bCIqbqG8UGXo1xTB8TK7wI7Uz0EB5-ej6fcD-_8&_nc_ht=scontent.fdet1-1.fna&oh=e0974b88079e8d809772da53b17f5ec2&oe=5DF366D7)
I need to do a quick soapy water test and see if the bowl plugs are leaking or not, but the epoxy looks to be pretty solidly on there, so we'll see. Everything is really quite clean inside. Nothing seems gummed up - everything moves quite easily and freely.
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Some other detail pictures:
The first one: some plunger on the underside of the air horn?
The second one: The accelerator pump seems awfully springy and wanting to pop out of the casting - this normal?
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First one: Power piston?
Second one: So I took this out, and it looks like the rebuild kit has a similar part, but with some kind of plunger in there? Mine does not have that. It also doesn't have the slots like mine does.
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Your kit has a high flow solid fuel inlet seat which is correct for that carburetor.....Cliff
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Ok, cool, so it just looks different and has that springy plunger thing and no slots because it is a better part, correct? Or could my needle/seat be stuck somewhere (or did someone remove it entirely)?
Just wanted to double check. I saw a white piece, I think I saw it referred to a secondary cam or something? Couldn't find where that goes - perhaps I missed something in disassembly? Everything else looks to match something I've taken out, which is good.
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Also, something I keep forgetting: Will I need a dwell meter to get this carb dialed in, since it is "electronic"?
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Just was able to pull all the epoxy off the plugs, so it's pretty apparent those are probably still leaking.
I see no way to remove these, is there some "easy" way? I won't have the time to tap and install plugs, unfortunately.
What epoxy should I use to cover them (and if they're removable, put in between the plug and where they go, so they stay in place)? I believe I saw Marine-Tex recommended before (JB weld makes a petroleum-resistant Marine epoxy now, too)? Of course nothing like that seems to be available locally, and tomorrow was going to be my full rebuild day, since this thing needs to be back on the car Saturday morning, so...
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Just sprayed some water where I thought I was supposed to with soap water over the plugs and didnt even see the water move. Hmm...
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Apparently I missed the paragraph stating that the later swaged-in plugs are much less likely to leak. Perhaps that is why I saw no bubbles - it may have been done as preventative, or by someone under the impression they'll leak like the earlier ones.
Maybe I am actually good to go? I see no discoloration that would, in my mind, present itself as a leak over time. Usually if it's been a good few days, the car takes a while to start, but if it's been like a day or two, it normally starts right up.
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(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69946393_10156663187063597_7445035502186528768_n.jpg?_nc_cat=107&_nc_oc=AQnnoZU8o5TcplVXMJoRko6QZ-IJwQRunmIy08l0a_B5JAGNtvGQIqCWJ-cJtvvBE57YbsD5Wcmw8W014jHgTicT&_nc_ht=scontent.fdet1-1.fna&oh=8eb98e2f251b0073753e7e48636eba73&oe=5DF737E3)
Sorry for the rapid fire in the last few posts - just was trying to get my thoughts down before we took the dog to the vet and I forgot. ;D
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have you verified with soapy water and air compressor that the plugs are not leaking? the last 3 quadrajets i have had at least 1 well plug that leaked. these are the newer swaged style that "rarely leak". i grind/file the top of the well plug flat so the swaged portion is gone. i then use a #8 drywall screw to extract the well plug. carefully drill an appropriate sized hole, screw in the drywall screw then using a pair of side cutters i "pop" the well plug out. you can purchase a repair kit from cliff, i personally use a 7/16 fine bottoming tap and then make my own plugs out of bolts. cliff recommends marine-tex, I use it at work occasionally so this is what I use. many years ago i had a gas tank that had been welded, we smeared jb weld on it as leak insurance. a year later it had softened and had a noticeable wet spot. others have had good luck with it, i personally have not used it since (about 10 years ago).
https://cliffshighperformance.com/simplemachinesforum/index.php/topic,4149.0.html (https://cliffshighperformance.com/simplemachinesforum/index.php/topic,4149.0.html)
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Yes, I put soapy water on them, and used a rubber tip on the blow gun (I did this a few times, since I felt like I wasn't doing it right because it wasn't leaking - then I read Cliff's note in the book that these don't usually leak).
I didn't block the other passages where air was coming out, but even still, I would have seen something happening around the plugs. There also is no visual indicator of a gasoline leak out of any of them, like there should be if there was a leak over time - it should eventually "stain" the casting.
The plug above the lean mix solenoid adjustment screw has been removed, so I'm thinking that the gasoline in the bowl likely evaporates from there, since that effectively opens the fuel bowl up to the atmosphere.
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So, plugs aside, let me try and sum up the remaining questions (and or revisions to said questions) I have from my gigantic mess of posts on the last page. ;D
1. I found the needle still stuck to the old float via a clip. I believe I have read this clip is not necessary (I see the new one does not have one), which makes sense to be, but I figure I'd be sure, as I can probably put the old one on the new one if it's of any help to the carb.
2. The needle seat in the kit looks to have no slots near the threaded base, whereas the one I removed from the carb does. What is the purpose of those slots in the old one - was that the incorrect one that someone put into this carb in the first place?
3. The secondary cam - this looks to go up top in the air horn? The screws I imagine are for the secondary air plates? Remove those, remove the shaft and install the new cam/spring?
4. Because I am (probably) an idiot, I did not count the number of turns of the lean mix screw before I removed it. I can see a distinct change in color that shows me, roughly, how far down it was originally, so that helps, but is there a good way to set that? The plug in the air horn above is removed, so I should be able to adjust it, on car, I believe - I may have to make a tool, though (I bought a flexible Lisle one for the lower two screws, if needed - rather have it and not need it, than need it and not have it). This may lead into the next question...
5. Dwell meter - do I need one?
Hopefully less chaotic of a (long) list than my 453,000 posts before.
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Updates from today - stopped just before putting the air horn back on just in case there is any feedback that requires me to access the components that would be under it.
Cleaned up the main casting and throttle plate a bit:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/69061301_10156666017678597_3565214436438310912_n.jpg?_nc_cat=104&_nc_oc=AQkcGN5wuCvt7lDiQ0p0cCqbdScifee_DffH4ymLPNlQwY_Xt8ov6zyIyC_rYJ6edPY&_nc_ht=scontent.fdet1-2.fna&oh=be95d77184cf5915053871ee40a61fd1&oe=5E12B7BD)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70486595_10156666017428597_8526822547256246272_n.jpg?_nc_cat=103&_nc_oc=AQnJzEZI7MSDDqms8Qg3JvZRN7YwtkdCS_6S5ad06VZPoIIM7ZHBdQA9dE4QSGOX1oc&_nc_ht=scontent.fdet1-1.fna&oh=ee91ef399b628aad53b5a3291fabd381&oe=5DFF8AE4)
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70760252_10156666017273597_6906514373557092352_n.jpg?_nc_cat=108&_nc_oc=AQlNfbkpWk9xRpBgQjY5Phr5lGYSWSBbWNapXt_NfYy2pBgeFdBfaZtLp4vW7ONRmN0&_nc_ht=scontent.fdet1-2.fna&oh=f6f6c86d5909cf378c93a8329602c6fa&oe=5DF75266)
Main casting and throttle plate reassembled:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69927734_10156666017608597_6576587845010456576_n.jpg?_nc_cat=110&_nc_oc=AQktFxUcHVs41FniUwdBCc1-Ki0Gk9q6q6TrI30J4q6C1PlUsv_eeGLmc9oRvagVpTI&_nc_ht=scontent.fdet1-1.fna&oh=4cfb7d633b1a9c1b42306b939a4ab462&oe=5E075B53)
New needle and seat installed
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70004216_10156666017493597_1041008490962747392_n.jpg?_nc_cat=109&_nc_oc=AQm76u028wpwkBG4vPZxH0Fj3bpNW0SiDrd2KdceyNUhNVsyCbWTOpE-DWPVAujqK8U&_nc_ht=scontent.fdet1-2.fna&oh=070b4666aead3e305993cc726b18825c&oe=5DFCD34D)
New float installed:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70265864_10156666017263597_4018876112334487552_n.jpg?_nc_cat=101&_nc_oc=AQnVtMItRPai5Dm0esrZhv9-A3_baLHja5W4D-mD3ZB295nym-v5iL2fkOA8SGH-iVo&_nc_ht=scontent.fdet1-1.fna&oh=ce09d2b72a8c763a94abf60a7f12d81d&oe=5E0F2F14)
Mixture control solenoid, metering rods and power piston reinstalled:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70333534_10156666017248597_5208711288892424192_n.jpg?_nc_cat=101&_nc_oc=AQnz2zoZaCz_KFaNwBHesDkC2H7-Z7WdEKfZJ5sWlewP-RaGecVnNGP_TAvvjd8WKzQ&_nc_ht=scontent.fdet1-1.fna&oh=a9826532deee861ea88fe76f1bb3abfc&oe=5E108604)
New accelerator pump installed and TPS reinstalled:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70037925_10156666017413597_5681548524886425600_n.jpg?_nc_cat=104&_nc_oc=AQnxnOcXg3MvqiYrJtO409MvSBtIwY7nMgd5PZyNUBYs6gvt45xq0oBZqarQu8YZzF8&_nc_ht=scontent.fdet1-2.fna&oh=7e014ac9bbe81d442483bb184865d04f&oe=5DF3C9D3)
I also reinstalled the choke housing and linkage.
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1. I found the needle still stuck to the old float via a clip. I believe I have read this clip is not necessary (I see the new one does not have one), which makes sense to be, but I figure I'd be sure, as I can probably put the old one on the new one if it's of any help to the carb.
If you are running a stock mechanical fuel pump I would opt to keep
it. I rebuilt a qjet for friends stock 1980 Firebird about 4 years ago and discarded the clip. Upon attempting to start the car would only run if I dumped fuel down the throat. Removed airhorn and found the needle sealed so well the original pump could not break it free. Installed clip, fired up immediately and ran great after setting idle speed, mixture, etc. Now could the pump have just been tired? Quite possible, I know Cliff runs an e-pump and has diacarded the clip.
2. The needle seat in the kit looks to have no slots near the threaded base, whereas the one I removed from the carb does. What is the purpose of those slots in the old one - was that the incorrect one that someone put into this carb in the first place?
Most likely an aftermarket replacement, it's clear that someone has rebuilt the unit before. Install the correct one supplied in the kit and move on.
3. The secondary cam - this looks to go up top in the air horn? The screws I imagine are for the secondary air plates? Remove those, remove the shaft and install the new cam/spring?
make sure to grind the tips of the screws off if it hasn't been done already. they are staked from the factory and there is a good chance they will snap off upon removal. i reinstall new screws with blue loctite once i get the flaps where i want them.
4. Because I am (probably) an idiot, I did not count the number of turns of the lean mix screw before I removed it. I can see a distinct change in color that shows me, roughly, how far down it was originally, so that helps, but is there a good way to set that? The plug in the air horn above is removed, so I should be able to adjust it, on car, I believe - I may have to make a tool, though (I bought a flexible Lisle one for the lower two screws, if needed - rather have it and not need it, than need it and not have it). This may lead into the next question...
I believe Cliff's generic starting point is 5.5 turns out from seated for the APT and 2.5 turns out from seated for the idle mixture screws
5. Dwell meter - do I need one?
Hopefully less chaotic of a (long) list than my 453,000 posts before.
I have an automotive DMM that has dwell and rpm settings. My digital timing light also has one. If you have access to a DMM that can measure duty cycle you can convert to dwell with this formula:
Dwell = (360 divided by # of cylinders) x (%DC divided by 100%)
Have you verified that the throttle shaft has been bushed? I have not come across a single unit that doesn't need bushings.
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Hot damn - thanks for the replies to all my (too many) questions!
The clip looks easy enough to remove, and I don't have to do too much work to get back down to that point, so I can pop that on. It just goes through one of those slotted holes on the end of the float, yeah?
I'll have to check the screws up top and see, but thanks for that advice - something I likely would have missed. So those four screws are for the throttle blades - remove those, pull the shaft out, and replace the cam/spring in the center?
Regarding the lean mix adustment screw, which also holds the mixture control solenoid down, it seems like when I removed it, it was basically tightened to "tight" - I'm not sure it should be any other way, because otherwise the solenoid would be pretty loose. I'm tightening by hand though - I get the double-D "socket" today, so it'll be easier to do than using my fingers. I tightened it back to the same "point" - and angle of the Double D - as what I removed. But that'll come out when I put the clip on the needle.
Looking at getting this, as it measures Dwell Angle...and has Prime Same Day: https://smile.amazon.com/INNOVA-3340-Automotive-Digital-Multimeter/dp/B000KIMHRQ/ref=sr_1_1?keywords=Automotive+DMM&qid=1568374886&s=gateway&sr=8-1
As far as the throttle shaft - I do not think I saw any bushings, but I have to look again. With the primaries open, there was probably 1/16"-1/8" end play or so, but as the blades closed, they centered themselves. The shaft rotates nice and freely, without any play around the shaft itself, just end play.
At this point, I don't have time to do the bushings, since the carb needs to be back on the car (and tuned) tonight. But it seems to spin freely, which is good.
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Cool, my buddy has a timing light with the dwell function, so I'm just going to borrow that from him today.
I've noticed various O-rings in a bag (where a new check ball was) as well as a small thicker round gasket (maybe an inch diameter) and then a very thin white plastic ring of a similar diameter - can't figure out where any of these go.
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Looking at the CCC instructions, it seems they recommend 3.5 turns back from bottomed out:
https://cliffshighperformance.com/wp-content/uploads/2018/10/1981-up-ccc.pdf
I will start with that, I'm thinking.
I'm going to see if I have something thin that'll fit down the boss of the air horn in the event I need to tweak from above - the tool I bought does not have a small enough DD for the LMS - it does fit the two idle mix screws on the bottom though.
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we want to know what the play is perpendicular to the throttle body, side to side is not a concern.
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Well shoot, I hooked in those holes...
No perpendicular play, only side to side.
All back together aside from the fuel inlet:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70486787_10156668652818597_4513247030155411456_n.jpg?_nc_cat=105&_nc_oc=AQlI0FaWay5ZEly1LcSOPR0d5T3zQhQySI9jlF6_EIX6DKA4yiuX30x_xZ_YRG2mWyznbiN3GirX7b0nh7kTH1-T&_nc_ht=scontent.fdet1-2.fna&oh=605499a6b60a8e85e5925f58644fc69e&oe=5E3A5AAB)
Much cleaner:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70155083_10156668652208597_3979283441647616000_n.jpg?_nc_cat=109&_nc_oc=AQlYHd1gOoiGKVhYJIIQ4eon43ZtcLEBWXgmnWtEfBqqZXBH24z9XobWEvWljwIu5W_y_5cIFapz02oqv8NYQ-WY&_nc_ht=scontent.fdet1-2.fna&oh=1e7af4f66652b3b9461f44c7035cfce7&oe=5DF41357)
All complete:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70284491_10156668652028597_1398851662688288768_n.jpg?_nc_cat=102&_nc_oc=AQm82xmFf3YE7wAY2j8eUHyZhHRW82bNxJiqOL3FnCc92lNMBw8Y4FpyusNJBZSYpt4PW3Avv9cN--N6YwvZPb8K&_nc_ht=scontent.fdet1-2.fna&oh=5e7c28c0fad30f45dca318406186fa50&oe=5DFD0C9A)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70328120_10156668652083597_3269014881612857344_n.jpg?_nc_cat=103&_nc_oc=AQl5k7qqsrKnwpv0eyL5Al4CDyeXASehZL0wt0ZcHCq2_K3IVEiutSTjatM3wq9wFi3ejHpJfaiNxzJ5UTOBI9yb&_nc_ht=scontent.fdet1-1.fna&oh=b9efb06282de2d8ae1b3b2f6521a3f34&oe=5DF69B61)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70183951_10156668652008597_340776771282534400_n.jpg?_nc_cat=110&_nc_oc=AQkbRHQlI96WINs_TLh337A-Lg7HnytVxdOjSbg4JM8YU7ZrV2GvLBsde9b6U82qAsQC0civ7E7azK5lq5ML0mpL&_nc_ht=scontent.fdet1-1.fna&oh=2bc0836f8edb52da29937cb29c1ded90&oe=5E07989D)
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70188781_10156668652128597_4725272578963275776_n.jpg?_nc_cat=110&_nc_oc=AQk-3ECLy0e_JTQHeWMF1Mrg9rSPbxHiRHuY5gYvLuISTTxW7TGbFoYkzxgznUMHai4P3t4I4niergjycsS7DT4u&_nc_ht=scontent.fdet1-1.fna&oh=83d9161dfade2074c8cefcd82caaad77&oe=5E10F3D6)
New versus old gasket - I'm not sure why they aren't the same:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70186673_10156668652138597_5255420613014585344_n.jpg?_nc_cat=105&_nc_oc=AQkhGzrQgCI1AGrlif9j76Sw-DA0L56yIrOy2spxeZ5hJwdfbBK4w5yq9DlDgYl22cwNecd9iyoTRXMUikRsgcC9&_nc_ht=scontent.fdet1-2.fna&oh=85fa3dfc2ed176b9c674de76d982956b&oe=5DF9D62F)
Carb back on the car - looks a bit cleaner than it did before:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/69915493_10156668651973597_4019475333286723584_n.jpg?_nc_cat=100&_nc_oc=AQkOM9HytkE5xoJ8YTl63twhTuTVwXrmTH3mUQHHG4UXcA1x5IvFPR1P_2DdEgqKagm83GErU4GTpAY9xpT3xqYP&_nc_ht=scontent.fdet1-1.fna&oh=978dee9cb8e0fade590e9eb0721d2c87&oe=5E0BF5F8)
Too bad after all this work, the car idles richer than shoot, and is pretty pissed off - I have succeeded in essentially making my vehicle worse.
I tried for a couple hours to see if I could mess with it, but it's dark out, I can't seem to get any dwell reading off the green diagnostic connector, and it's still stupidly rich. It also tried to restart once on the first shut down, so, that's a great sign.
Won't be taking the car to dyno day tomorrow, so, yep, not a good night for me. :(
Going to need a lot of help trying to figure out how on earth to get this car running properly, it seems.
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did you accurately set float height or install "as is"? have you verified base timing? did you change how clip is hooked onto float? the needle can "hang up" if not in correct position. I don't know much about CCC carbs but i know there are many adjustments that must be set to correctly run.
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Is it flooding?
Did you install new "O" rings on the upper idle airbleed adjusting screw?
Did you remove and clean or at least run something thru the idle tubes to verify they aren't plugged up?
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So, I didn't set float height (I don't think it was mentioned in the book too much - just said that it should be just above the upper surface of the casting, which it is) but it doesn't appear the be overflowing. I did, unfortunately, clip that clip into one of the holes, rather than over the edge, as I had it back together before I saw that.
Is there a way I can tell if it's flooding the carb?
I did not install new O rings on the upper idle airbleed screw, but I also did not remove it.
I ran solder wire that fit perfectly through the idle tubes to verify they were clean (solder wire came out the bottom, so they made it all the way through).
For reference, I set the lean mix screw to 3.5 turns backed out from bottomed. It looks like the rich mix is pre-set and cannot be adjusted (though that plug is also gone). I had found a broken small screwdriver in my yard last year and put it in my toolbench (before I knew it was actually missing the end). I almost tossed it this year but thought "no, this might be useful somehow" - turns out it is, I ground a slot in it that fits around the tiny double-D on the LMS and the RMS and fits down those bores. LMS should be good, but at least I can tweak if needed - though it doesn't seem like I need it to change.
Also worth mentioning - and likely not helping one bit - it sure sounds like I have a colossal vacuum leak - may have just been the idle misbehaving anyway, because it was not being consistent at all - but it sounded like when I sprayed carb cleaner near the front of the carb-to-intake gasket, the idle went up. But again, that may be a function of the idle being all over the place.
Something else that might direct our thoughts to a potential culprit: If I rev it, the revs hang and very slowly come down - did it in the engine bay to observe the throttle shaft behavior - it is snapping back, completely closed, as intended...but something else is keeping revs up.
Perhaps that's part (or all) of the issue. Could be so much extra air coming in, the O2 is seeing it, trying to compensate by fattening it up a whole lot. When I went to shut it down the first time, it tried to stay running for about a second.
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you need to completely rebuild the carb correctly. this includes installing most if not all of the parts supplied in the kit. check trouble areas leaking well plugs, worn throttle shafts, stripped threads, binding linkage etc etc. you also need to setup the carb as it came from factory, setting float height is critical. i told you how correctly hook the needle clip yet you didnt fix it and ran it anyway? did you read the mercruiser bulletin i posted? cliff's book is not a "how to" rebuild step by step it discusses theory and how to modify the carb. there will be a sheet that was sent with your kit, you can look up your carb number and it will tell you the float height. if you spend a few hours reading or searching on this forum you will find most of the answers and methods that are needed to successfully rebuild & modify these carbs. there are also a ton of youtube videos on rebuilding as well.
as far as a vacuum leak from the carb did you check to see if the airhorn or main body was warped? over torquing the mounting bolts will cause warping. also i the idle tubes are in a blind hole, i am not too sure how you were able to see the wire sticking out of the other end. i push wire in until it bottoms, mark the wire then check the other side, if they go in the same distance there is a good chance they are not plugged.
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i told you how correctly hook the needle clip yet you didnt fix it and ran it anyway?
By the time you sent that, the carb was already rebuilt and on the car, so...
What sheet was sent with my rebuild kit? I did not receive any kind of sheet, aside from the link to this, which I always had up on my computer to reference: https://cliffshighperformance.com/wp-content/uploads/2018/10/1981-up-ccc.pdf
The book is pretty step by step, but I don't recall any thing related to setting float height, aside from it being just over the top of the casting surface, which it was. Was the same as the one in there before.
There are four holes right there. Two bottom out, two go through the bottom of the carb. Everything was clean.
I torqued the mounting bolts to the 12 lb-ft specified in the service manual, so those are to spec. But it definitely sounds like that's where the big leak is, as moving my hand near there "blocks" the sound.
Didn't check to see if the air horn or casting were warped, but the gasket interface seemed pretty consistent.
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You need to set the float correctly and hang in the inlet needle clip from behind of the float arm, no way around this.
If not, you will never get the carb working properly.
Follow the instructions for a basic rebuild in order, step by step:
https://cliffshighperformance.com/wp-content/uploads/2018/10/1981-up-ccc.pdf
https://cliffshighperformance.com/simplemachinesforum/index.php?action=dlattach;topic=4148.0;attach=1383;image
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It looks like the clip could bind and cause the needle to stick open - but with both that, and a float that is maybe too high, wouldn't it overflow the carb with gas, and not just run slightly rich? Or can it cause rich running without overflowing the carb?
If I'm able to re-use the same gaskets and take it apart again, then I'm not opposed to doing that. Removing it from the car isn't exactly difficult, nor is getting the air horn off (the TPS plunger is a bit of a bitch, though).
That PDF doesn't really make it clear how to accurately adjust the float. Should it be 3/16" below the top of the main casting or 3/16" above the top of the main casting? The book stated the float should come above the main casting.
Is it worthwhile to get the Quadrajet float gauge to do this, or is it easy enough to do with a straightedge and calipers?
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A too high float setting and binding inlet needle due to misplaced clip can and WILL make the engine run rich without flooding, but flooding does occur from time to time.
A new gasket can be reused many times on the same carb.
The procedure is described on page 2 figure #3 and the fuel level settings are in adjustment data tables on pages 3, 5 and 6.
What is the application number on your Q-jet?
https://cliffshighperformance.com/wp-content/uploads/2018/10/1981-up-ccc.pdf
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Ah, okay, that would make sense then - along with the vac leak pulling in extra air, pissing off the O2, making it dump even more fuel in - vicious cycle.
Carb number is 17081207
And cool - I figured so - it's only seen one heat cycle anyway.
I'm still puzzled why there was such a stark difference in the gasket that was on the car and the new one:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70186673_10156668652138597_5255420613014585344_n.jpg?_nc_cat=105&_nc_oc=AQkhGzrQgCI1AGrlif9j76Sw-DA0L56yIrOy2spxeZ5hJwdfbBK4w5yq9DlDgYl22cwNecd9iyoTRXMUikRsgcC9&_nc_ht=scontent.fdet1-2.fna&oh=85fa3dfc2ed176b9c674de76d982956b&oe=5DF9D62F)
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I already posted a picture of how to set float height, i also suggested searching on YouTube. we are trying to help you but you seem to not want listen. i am tired of repeating myself this will be my last post in this thread, good luck with your rebuild.
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Don't want to listen, what are you talking about?
I simply asked if I need the tool to do it, or if I can use a straightedge and calipers - the image you posted shows a special tool (which Cliff said I would not need, earlier in the post). How is that "not want listen"?
I do appreciate the help in this thread, but if you feel you must go, then I can't stop you.
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Pulled the carb back out on Wednesday and got the air horn pulled off on Thursday, then I adjusted the float to 11/32" (as specified) down from the surface of the main casting and put the needle pull clip in the correct spot.
Pull clip:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70575342_10156686046648597_6573492578044346368_n.jpg?_nc_cat=103&_nc_oc=AQmBwMCi5NUKyE2y7N3yQeSlO3dCzW4VY1CHfuyDcBNvfaDadS-dW1TCp-zeZlqoXrU&_nc_ht=scontent.fdet1-1.fna&oh=f5b0d6f3acf5b1929b62ae8b08c4c592&oe=5E01A4F4)
Float adjusted to the proper level - a good bit lower than it was. Oops.
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/70534544_10156686046668597_325742955522424832_n.jpg?_nc_cat=102&_nc_oc=AQl8lhWXZrQgC_FDawvm4znTOw6XS800OTSi56RLVkh1-yENu08AB1GjLO7B19aJRcs&_nc_ht=scontent.fdet1-2.fna&oh=ad0bf0eb5d6267d10d945817682665d9&oe=5E0059A8)
The pull clip sits pretty loose there, so putting the float/needle back in after adjusting the float to check the height was always fun. Is it supposed to be that loose to the float?
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My wife took a couple of (blurry) pics of the float measurement.
I don't have a super-wide vernier-style caliper, but I was able to go off the corner of the casting there and get pretty close to the 3/16" in from the end that it calls for.
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3/16" is not the float height.
this thread was painful to read.
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3/16" in from the toe of the float, like the measurement method calls for.
The float height is 11/32" down, which is what I said the post before (hence the 0.344" on the caliper).
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Pulled the Idle Air Bleed Valve out to check the O-rings since, for whatever reason, I didn't the first time. Upper O-ring looked mostly fine, but the lower one was a bit...flat:
(https://scontent.fdet1-2.fna.fbcdn.net/v/t1.0-9/71497642_10156702317663597_1715663384042536960_n.jpg?_nc_cat=111&_nc_oc=AQmhT2btOOMGCgU4RdPwOkrlzfj_pFF1QCt4ofpvBl1-PkrXfBnYxXrfFsFDuUOgkam6bPrUeEf5PAkPyYpiXfI5&_nc_ht=scontent.fdet1-2.fna&oh=09ddd6e6ac40ee9860534e32a986643c&oe=5DF4065A)
Upper O-rings - new (left) vs old (right):
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70962490_10156702317633597_5358123073587380224_n.jpg?_nc_cat=107&_nc_oc=AQnQ-ZFZNHgyILyk4lgSlP87JK66IffN6RknWWZ8leYK-kdjYJHvU-Zm3lde5Ubx64k_SLaU6Qq8-fbZornVQdBP&_nc_ht=scontent.fdet1-1.fna&oh=f3c893c96b87c0e8a5df23a96d0f13e4&oe=5E28F12C)
Lower O-rings - new (left) vs old (right) - can see how much "flatter" the old one was:
(https://scontent.fdet1-1.fna.fbcdn.net/v/t1.0-9/70829858_10156702317683597_5042449991012974592_n.jpg?_nc_cat=110&_nc_oc=AQlk41O-wVJxi1ghcl6TcNB2NazIs52bBWNo-sdSkc0zN0QKWANH89UwkNKsYUhJCRcVcrrjs_3qcdtPi-A6AGNY&_nc_ht=scontent.fdet1-1.fna&oh=7032f4a2dd8a818036660fcc8ad2a5cd&oe=5DF004E3)
I adjusted it 4.5 turns back from bottomed.
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Even the slightest air leak past those "O" rings will make tuning impossible. In most cases when I get into a CCC carb they are cracked, split and leaking pretty bad. Since they route air to the idle system they will have a significant impact on idle fuel control at the mixture screws, and fuel to the off idle transfer slots which can lead to poor idle quality, and lean off idle (hesitation/stumble/bog) even if everything else in the carb and computer stuff is working correctly......Cliff
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Good to know! I would honestly not be surprised if that lower O-ring was not sealing all that well, given it was pretty squared off.
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Carb's back on the car - doesn't run perfect by any means, but boy is it night and day compared to what it was like the last time. Now I think I can work with this and get it dialed in (hopefully).
Don't seem to have the vacuum leak (as audibly) like it did last time, nor does it smell rich as hell. Seems to idle a bit low, but maybe that could be due to the idle air bleed being back to the "stock" setting. Need to get the dwell reading to work and get that all tweaked.
Seems like occasionally it has a really low idle - especially if you flick that "lever" (can't find the proper term) down between the choke and the main casting. If you don't, the idle seems to stay high.