Help needed on carburetor issue...

Jordan · Post by **Jordan** » Tue May 30, 2017 4:18 pm

Gentlemen:

I'm having a carburetor issue on my CJ2A. Not sure who the carb manufacturer is, but it's a fully rebuilt carb (bought it a few years ago, but its been sitting on the jeep a couple years since I installed it, but without any use). Here's the problem: when I depress the throttle, the engine hesitates and dies, unless I back off the throttle or give it some choke. I can give it throttle and keep it running, but only if I choke it at the same time. In other words, I have to have the choke pulled out to run this thing much above idle, otherwise it dies. Gas is fresh. What might the problem be??

Any suggestions are appreciated.

Thanks,

Jordan

Post by **wesk** » Tue May 30, 2017 9:42 pm

We could all make some stabs in the dark at your problem but we really shouldn't. Let's get back to : What carb are we talking about????? Since we have a non-standard carb, what else is non-standard CJ2A? Post some photos of the engine bay and a few closeups of the carb!

If you have the L134 engine then you usually only find either a Carter WO or a Solex 32 PBIC. The make & basic model #'s are cast in the carb housings. The specific part/series number is on a triangular shaped tag attached to the carb.

Jordan · Post by **Jordan** » Wed May 31, 2017 10:48 am

Wesk:

The carburetor is a Carter YS. I'll shoot and post photos of the carb and engine bay later today.

Thank you,

JOrdan

Hawkshadow · Post by **Hawkshadow** » Wed May 31, 2017 1:04 pm

Jordan, are you confident that the timing is set exactly before we dive in to carb issues?

Post by **wesk** » Wed May 31, 2017 1:11 pm

So you are running a YS637S waterproof carb on your CJ2A.

As Hawkshadow mentions incorrect timing and/or inoperative governor advance or in the case of the CJ2A if you have the civvy distributor then that would be inoperative vacuum advance will give you a stumble on acceleration.

The YS637S carb will give you a stumble if the vacuum operated accelerator pump is malfunctioning. Same issue requiring choke when the metering rod vacuum operated diaphragm is malfunctioning.

Use a copy of TM 9-1826A Carter Carbs MX to assist you with troubleshooting. You will find excellent circuit charts in there.

Jordan · Post by **Jordan** » Wed May 31, 2017 3:29 pm

Thank you gentlemen. Your advise is very much appreciated. I'll dive into the TM and go from there.

Jordan

Jordan · Post by **Jordan** » Thu Jun 01, 2017 1:34 pm

Hawkshadow wrote:Jordan, are you confident that the timing is set exactly before we dive in to carb issues?

Hawk:

Will double check timing.

Thanks,

Jordan

Post by **wesk** » Fri Jun 02, 2017 12:09 am

Be sure to inspect and check the governor advancing mechanism for being stuck or rusted into a fixed position. You can either disassemble the distributor or just remove the cover and try to rotate the rotor with your hand. It should rotate in one direction only about 5 degrees or so and then spring back on it's own.