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Sat Mar 06, 2010 5:52 pm

Stock 36 hp I can not seem to get it to idle down I have just finished sealing up all th air leaks (which were many) but I cant seem to get the enigne to idle down.
The CO adjusting screw does absolutely nothing I can turn it all the way in or all the way out My timing was bang on at 7 degress but I have since retarded it in a failed attemp to slow the idle down
The carb was rebuilt..(by me) I am no expert but I have played with these cars for over 10 years and have done lots of my own carb rebuilds with no problems
Any and all suggestions are appreciated
Tom

Sat Mar 06, 2010 6:57 pm

i had this problem once , i dont know if it will be your problem but ill still tell you. I was useing an aftermarket air cleaner and the adjusters at the bottom of the aircleaner was holding the throttle open. This was a mind boggler for me for 2 days hahahahaha !! Finally i turned the ar cleaner and idle went down ... just a suggestion. Good luck.

Sun Mar 07, 2010 4:45 am

Thanks Painted..but I havent even got to putting the oil bath back on yet...it really is a frustrating mind boggler
Tom

Sun Mar 07, 2010 11:33 am

Take the mixture screw out and check it is not broke on the end or has a worn step on the taper.If the screw has been wound in hard the seat for the screw could be damaged and your carb will never run right.You could just try another mixture screw and see if it improves.Is the choke off?

Sun Mar 07, 2010 12:07 pm

You have a 28 PCI carb., correct?

I had this problem on a slightly later carb., the 28 PICT and it turned out someone had drilled out the idle jet so it was larger. This prevented the mixture screwed from stalling out the car when turned all the way in. Replaced that and everything was fine.

I'm assuming the throttle shaft in your carburetor is not sloppy and therefore not leaking.

Easy stuff which you probably already checked:
Is the idle speed screw completely backed off so it isn't even touching and you still have a high idle?
Is the accelerator cable "loose" meaning the carburetor arm is returning all the way shut?
Is the choke all the way off?

Post some pics of the carburetor and engine...

Sun Mar 07, 2010 3:46 pm

Thanks
Yep choke is all the way off and cable is loose ... I will take out the mixing screw tomorrow night and see if it is damaged I should have tried that yesterday ..if that isnt it I will try a 28 PICT-1 that I have ....getting a little frustrated with this engine it is my first 36hp

Sun Mar 07, 2010 7:02 pm

Did you adjust the timing?Too much advance will cause a fast idle.

Sun Mar 07, 2010 11:29 pm

Don't forget all the parts for the accelerator cable I had this happen to me the spring wasn't strong enough to return it to low idle

Mon Mar 08, 2010 6:29 am

Sunroof53 wrote: Did you adjust the timing?Too much advance will cause a fast idle.

Sticking counterweights in the distributor will have the same effect. Using WD-40 as a lubricant will cause this problem, as it gums up over time.

Sat Mar 13, 2010 5:42 am

Well It is confirmed it is all carb problem. I put on an old ratty 28 PICT-1
and it runs great. I guess I will try another rebuild on a different 28 PCI
Maybe somebody messed with the idle jet like yours Everett.
Thanks for all the suggestions
Tom

Sun Mar 14, 2010 4:45 pm

Hey there!
With the same symptoms, I found that the idle circuit
in the carb was plugged, try taking apart, soaking in
carb cleaner, blow out every opening with compressed air.
It worked for me!