My Willys 3A and 3B Community

3A, 3B, DJ Technical Knowledge Base => "Original"-- Technical Questions, Answers, Observations => Topic started by: Weedhopper on March 27, 2011, 07:54:02 PM

Title: It runs but it won't idle
Post by: Weedhopper on March 27, 2011, 07:54:02 PM

I reach the stage in my rebuild where I started the engine today. All went well with only one small oil leak at the filter canister, the gasket for the lid was bad. My problem is that I can't get the engine to idle without the choke closed. The idle mixture screw doesn't seem to make much difference wherever it is adjusted. The engine runs smooth at 1000 rpm and up, anything lower it sputters and stalls. I rebuilt the WO carb., with a master kit,  Any ideas?

Title: Re: It runs but it won't idle
Post by: Carls_jeep on March 27, 2011, 09:50:36 PM

It sounds like the idle circuit is plugged. How did you clean the carb before the rebuild?

Title: Re: It runs but it won't idle
Post by: RA472A on March 28, 2011, 12:41:24 AM

Sounds like it could be a vacuum leak also.  Make sure carb is tightened down with a good gasket under it.

Title: Re: It runs but it won't idle
Post by: Weedhopper on March 28, 2011, 10:38:45 AM

I disassembled the carb and cleaned it in Berryman Chemtool, it was reassembled with a master rebuild kit from Walacks. It's possible that I have a blockage in the idle circuit.  I'll give that a check. The carbs base gasket is new but worth a check to see it it's leaking. Thanks

Title: Re: It runs but it won't idle
Post by: F Bill on March 28, 2011, 10:58:46 AM

This is way out in left field, but is your PCV valve operating properly? A stuck one can give you a big vac leak...

Title: Re: It runs but it won't idle
Post by: Weedhopper on March 28, 2011, 12:31:25 PM

The PVC valve was disassembled and cleaned also, but it worth a look to see if its working like it should.

Title: Re: It runs but it won't idle
Post by: rocketeer on March 28, 2011, 12:42:34 PM

If it runs with the choke closed that means it's starving for fuel. As mentioned, check for vacuum leaks and if the PVC valve is functioning.

Recheck the metering rod adjustment. Make sure to back out the throttle stop screw before making the adjustment. One often overlooked little item is the tiny spring on the metering rod. The metering rod won't work correctly if that spring is missing. The spring holds the rod down against the pin. If it's missing the rod can float around making it impossible to achieve a correct setting.

(http://i863.photobucket.com/albums/ab191/rocketeer_2010/Jeep/carb_spring.jpg)

Larry