Hesitation off idle

[Trooper182]

Ok so now that I have fixed my melting hose issue my 97 GTX runs great except for it hesitates off of idle. If I stop and let it idle and then try to punch it it will hesitate and sometimes stall. Also does this if i shut it off and then start it later and try to go. I have to feather the trottle a bit and then it takes off and is fine. I have already rebuild the carbs with genuine rebuild kits, pop off is at 35 on both. New fuel lines, fuel selector valve, fuel filter O-ring and filter, new plugs. Compression is 151 on both cylinders. Any ideas?

 

[LikeabossTM]

Ok so now that I have fixed my melting hose issue my 97 GTX runs great except for it hesitates off of idle. If I stop and let it idle and then try to punch it it will hesitate and sometimes stall. Also does this if i shut it off and then start it later and try to go. I have to feather the trottle a bit and then it takes off and is fine. I have already rebuild the carbs with genuine rebuild kits, pop off is at 35 on both. New fuel lines, fuel selector valve, fuel filter O-ring and filter, new plugs. Compression is 151 on both cylinders. Any ideas?

If your popoff is good I'd guess your lever arms aren't high enough under the diaghram (level with the body of the carb floor). Or maybe transition ports aren't clear.

Whatever it is, sounds like a lean hesitation off idle.

 

[Trooper182]

ok so I verified my pop off again and am at 35/34. I'm still getting hesitation/dying off idle. Should I attempt to lower my popoff some or perhaps try adjusting the lowside screw some more? Right now I'm set to factory specs.

 

[Pwnage1337]

Chasing a similar issue on my XP. I'm gonna check Rotary valve cover clearance.

I was reading and it sounds like if the clearance is too large, the cylinders can "steal" each other's air/fuel mixture at lower RPM. I also have a hard starting when hot symptom that makes me think my clearance is excessive.

I am going to do one thing at a time instead of a bunch at once so I know what took care of the issue.

Now if SBT would just ship my RV cover I ordered....

 

[Trooper182]

Chasing a similar issue on my XP. I'm gonna check Rotary valve cover clearance.

I was reading and it sounds like if the clearance is too large, the cylinders can "steal" each other's air/fuel mixture at lower RPM. I also have a hard starting when hot symptom that makes me think my clearance is excessive.

I am going to do one thing at a time instead of a bunch at once so I know what took care of the issue.

Now if SBT would just ship my RV cover I ordered....

I have no issues starting back up when hot. Will idle fine all day long. Just hesitant when starting off. I'm going to order new springs since I reused the original ones when I did the carbs rebuild and reset my popoff. Maybe see if I can get it a little lower.

 

[Pwnage1337]

You could try opening up the low speed screw a little bit (1/4 turn) to see if that helps clear your problem up, then you can verify that it is in fact a lean mixture issue that is causing your issue.

In theory the hesitation would be reduced by richening the low speed mixture.

Then you could pull the carbs and clean all the passages again, and re-verify popoff. If you are going to check popoff it would only take a few more mins to disassemble carbs and clean all the passages with compressed air and carb cleaner