Carb? Wht Wont Idle Return to normal???

[DanStew]

Well my cabr problems seem to be a thing of the past, but one thing that seems to linger is that if i really rev my engine, sometimes the idle will not return to normal. I run around 800 rpms at idle. Last weekend i revved the engine to get the attention of my club buddies and then engine would not settle down. it kept the idle to about 1500 - 1600. This was a real bugging problem. I had to keep the jeep in 4 low to keep it from rear ending the other jeeps in my group. But after i shut the jeep down and let it cool down, i will start it up and it will return to normal. Does anyone know what could cause this?? I have done vacuum readings and everything seems to be kosher. It does not happen all the time, but i would like to know what is causing this to happen. By the way the carb is a 390 cfm holly 4 bbl.
Thanks
Dan Stewart 1963 CJ5 "Caloosa Jeepers" member

[ozarkjeep]

sounds like a linkage binding problem, maybe the choke fast idel cam linkage?

not real freindly with Holley 4bbls, so probably not any help



OzarkJeep

I love the U.S.A.

[Drury]

Also your throttle cable could be dirty.

78 CJ7 Golden Eagle/TR Ignition/Weberized

The last time I had a "sticky" carb, it turned out to be the throttle cable. It had fraid inside the cable sheathing and kept jamming up. It took 4 months of fiddling with the carb before the cable finaly snapped and I found out what the problem had been.
Thank God for multi-tools.
Check on the choke linkages first though. That seems like the perfect idle for a fast idle cam.


'88 Sahara, 4.2 that runs. The rest is getting there![img]/wwwthreads_images/icons/blush.gif[/img]

[DanStew]

Thanks for the replys guys...
I know it is not the throttle linkage, because i run a straight rod from my pedal and when this problem was happening i was pulling on my pedal and it didnt fix, and i also popped the hood and fiddled with the linkage. I havent checked the choke setting. I dont have the electric choke hooked up. I pulled off the linkage to the top plates. I just finished fixing my taillights, so i will go for a ride later tonight and see if it is still a problem.

Dan Stewart 1963 CJ5 "Caloosa Jeepers" member

Make sure you have a return spring hooked up somewhere to your linkage. Don't just count on the spring in the carb.

[MyRide]

What about just cleaning the linkages with carb cleaner? How's the throttle spring tension?
Give it a try, Scott...

My Rides
1979 CJ-7: 304, 3spd, much is my rebuild
1983 CJ-7: 258, 5spd, for Peru Excursion
1989 XJ: has seen every state except Hawaii

In search of lost paths and distant locations...

Sounds like a problem with your fast idle cam. When the engine is cold the choke brings up the fast idle cam and the engine idles higher (usually between 1500-1700rpm) in order for the engine to warm up faster. As the engine warms up the choke plate slowly opens and the cam drops down, the engine then idles at curb idle. It seems that when you open up the throttle the cam is coming up and staying there. Try checking if the choke is set properly, if its to tight the cam won't drop down. Also it might be your fast idle cam adjustment screw is not properly set. Hope that's some help.