Q jet idling issue

[Jstock85]

Qjet on 85 c10. did a rebuild kit several weeks ago and has been running great. went out for a drive yesterday and idle in drive is choking out. RPMs drop to about 300. Park and neutral RPMs hover around 500-800. Any suggestions?

[oldpurple]

I would check for vacuum leaks. You can use carb cleaner to spray around various areas while it's running, and you will hear the engine speed up a bit. Don't over tighten the mounting bolts, especially the two long ones at the front. I like to use an inch pound tq wrench on them.

What kind of gasket did you use between the carb and intake? I had a crappy thin one (came with a cheapo kit) that wasn't sealing properly, and a better 1/4" one fixed that problem.

I would also check the screws that hold the air horn to the main body, and if you're removing the carb I would check the ones holding the throttle plate onto the body. I found that after a few heat cycles some of mine really loosened up enough to cause some leaks, especially the two down in the primary bores. Maybe the factory used some sort of threadlocker?

[Jstock85]

Got the kit from cliff's. Several recommended it on this board. The plate is one of the 1/4 in thick ones. Im hoping the problem is a simple fix. The vac lines seem secure when i gave it a quick check. I will check the bolts and maybe that'll fix the problem. Thanks for the response.