Author Topic: 17056264 carb issue.  (Read 2553 times)

Offline DeCaff2007

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17056264 carb issue.
« on: December 31, 2016, 01:03:42 PM »
Ok here's my issue.  Bought carb off ebay, cliffs SP kit, and rebuilt it to the letter using cliffs book.  Wasn't too awfully difficult, but it gave me some grief..  Even though I had ZERO parts left over, I'm pretty sure I'm missing something.  Hot air choke for one, the linkage that connects the hot air choke to the primaries, and I just might have missed something in the rebuild.

So, that said, I bolted my carb to my 76 Trans Am, gave the throttle linkage a few pumps, and definitely saw fuel spraying into the bowl.  Good.  So I turned the key and it will crank but won't start.  I have spark, timing is dead on, but then I held the throttle plate open and watched the fuel drain to the intake manifold.  Turned the key and it fired right up... for about 2 seconds, and died.

So wash, rinse, repeat... why is the carb not allowing fuel through to the intake? 

Any thoughts before I tear this apart again and make a bigger mess?

Offline Ethan1

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Re: 17056264 carb issue.
« Reply #1 on: December 31, 2016, 05:52:55 PM »
Ok here's my issue.  Bought carb off ebay, cliffs SP kit, and rebuilt it to the letter using cliffs book.  Wasn't too awfully difficult, but it gave me some grief..  Even though I had ZERO parts left over, I'm pretty sure I'm missing something.  Hot air choke for one, the linkage that connects the hot air choke to the primaries, and I just might have missed something in the rebuild.

So, that said, I bolted my carb to my 76 Trans Am, gave the throttle linkage a few pumps, and definitely saw fuel spraying into the bowl.  Good.  So I turned the key and it will crank but won't start.  I have spark, timing is dead on, but then I held the throttle plate open and watched the fuel drain to the intake manifold.  Turned the key and it fired right up... for about 2 seconds, and died.

So wash, rinse, repeat... why is the carb not allowing fuel through to the intake? 

Any thoughts before I tear this apart again and make a bigger mess?

 Where is your idle mixture screws set at? Idle speed screw set at?
Ethan

1972 Chevelle

(oo______oo)

Offline qjetsrule

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Re: 17056264 carb issue.
« Reply #2 on: December 31, 2016, 07:06:57 PM »
if the choke opens too far and the engine is cold it will die also. good luck

Offline omaha

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Re: 17056264 carb issue.
« Reply #3 on: January 01, 2017, 02:16:15 AM »
...is it possible that the choke is closing all the way because of the missing linkage. If the choke does not open at all, it will kill the engine. Make sure the choke is open at least somewhat. {wire it open etc.} It should run if it is cold even if you have to modulate the pedal. Usually the choke pulloff will open it enough but if is not adjusted correctly or inoperative you will have problems. Other than that, if the choke is opening, then the idle supply is being blocked. cold weather will kill the engine also but it seems like if you could keep it running at least by pumping the pedal a bit til it gets some heat into it you should at least get it to high idle with a high idle setting. So double check throttle opening adjustment and ,idle screw adjustment, {depends on what screws you have, regular or fine thread}sometimes the fine thread screws will need to be turned quite a few turns before you will get a good idle, and make sure the choke is open at least 3/16 to 1/4 while its trying to start. Happy New Year!!!

Offline Ethan1

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Re: 17056264 carb issue.
« Reply #4 on: January 01, 2017, 11:50:02 AM »
 And, yes, it is VERY easy to forget parts on these carburetors once there together. I sometimes even have my problems! :o
Ethan

1972 Chevelle

(oo______oo)

Offline DeCaff2007

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Re: 17056264 carb issue.
« Reply #5 on: January 02, 2017, 05:15:16 AM »
Where is your idle mixture screws set at? Idle speed screw set at?

Wherever Cliff's book said to set them at, that's where they are. 

Gents, thanks for all the replies.  We did mess with the carb a little more.  My psuedo f-i-l even came over and checked things out (mechanic for 40+ years).  He said my carb isn't perfect, but the real problem is the timing.  Also, I do really need to find a hot air choke and the associated main shaft. 

Guess I'll be tearing back into that next.  I'll post back when I get some more results.

Ok thanks again for the re

Offline 429bbf

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Re: 17056264 carb issue.
« Reply #6 on: January 07, 2017, 02:18:18 PM »
unless your dead set on a hot air choke go ahead and put one on . i wouldn't waste the time unless your doing a restoration or some thing . order a nice electric kit from cliff and install get set right and problems solved .imo

Offline Ethan1

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Re: 17056264 carb issue.
« Reply #7 on: January 15, 2017, 01:54:06 PM »
unless your dead set on a hot air choke go ahead and put one on . i wouldn't waste the time unless your doing a restoration or some thing . order a nice electric kit from cliff and install get set right and problems solved .imo

 This is the way to go! Stop messing with the hot air choke. Conversion is pretty straightforward. Unless your car is stock and you're trying to stay stock, I would go with an E-choke conversion. JMHO.
Ethan

1972 Chevelle

(oo______oo)