Heavier throttle (mostly) issues

[MP81]

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.

[MP81]

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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. 

[tayto]

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

[MP81]

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.

[MP81]

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. 

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.

[MP81]

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:




Main casting and throttle plate reassembled:


New needle and seat installed


New float installed:


Mixture control solenoid, metering rods and power piston reinstalled:


New accelerator pump installed and TPS reinstalled:


I also reinstalled the choke housing and linkage.

[tayto]

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.

[MP81]

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.

[MP81]

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.

[MP81]

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.

[tayto]

we want to know what the play is perpendicular to the throttle body, side to side is not a concern.

[MP81]

Well shoot, I hooked in those holes...

No perpendicular play, only side to side.

All back together aside from the fuel inlet:


Much cleaner:


All complete:





New versus old gasket - I'm not sure why they aren't the same:


Carb back on the car - looks a bit cleaner than it did before:


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.

[tayto]

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.

[Cliff Ruggles]

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?

[MP81]

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.