High idle

[BQUICK]

Have high idle.
I reset points from .028 to .020. Idle still high. Throttle all the way closed.

Have not checked timing yet. Any thing else I should look for?

[Dale Finch]

I'm certainly not a carb expert, but if you do a search, I think you will find there is an idle adjust screw on the top of the carb. There are free manuals that include the owners and service manuals available from the QUICK LINKS in the above left corner.
Check page 13:
http://farmallcub.com/rudi_cub/www.cleancomputes.com/Cub/Blue%20Ribbon%20Service%20Manuals/GSS-1132%20Fuel%20System/GSS-1132%20Fuel%20System.htm

[Don McCombs]

Page 13 refers to the Zenith carburetor. Your 1964 Cub should have an IH carb. Check the procedure on Page 10 for adjusting the governor to carburetor control rod. Point gap has no relationship to idle speed.

[BQUICK]

I figured it affects timing so could affect idle rpm.
I notice governor spring looks weak and also throttle shaft bracket loose.

Ordered carb kit with new shaft and a new gov spring.

[Steve Butram]

Back the idle screw out a half turn to see if the engine slows down. I'm guessing you need to adjust the the governor linkage. then set the timing.

[BQUICK]

Which idle screw?....one on linkage or mixture?

[staninlowerAL]

The only adjustment on the IH carb adjusts the air flow mixture. The Idle screw adjustment is on the linkage above the carb.

[Dale Finch]

The only adjustment on the IH carb adjusts the air flow mixture. The Idle screw adjustment is on the linkage above the carb.

That's the one I was thinking of...a simple mechanical limiting stop screw.

[inairam]

Before you rebuild the carb and replace the governor spring ( both things most cubs need) adjust the linkage between the governor and the carb per the manual. If the cub starts and runs the carb is probably ok.

adjust the linkage between the governor and the carb first and then do the fine adjustment on the carb for low idle second. You will have to do it again when you pull the carb to rebuild or replace the spring but it should be less.

Have you separated the cub recently? The linkage between the throttle and governor will fit both ways but there is a front and back end. If you put it in backwards it will fit but will mess up the RPM control with the throttle.

[Don McCombs]

This is the control rod we are all talking about.

[BQUICK]

Hmmm....that could be it...clutch was recently put in.....

[BQUICK]

Clevis is toward front of Cub....didn't remove it to do clutch.

[Glen]

Hi,
I sent you a PM, you get to it at the top of the page.

Below is a pic from TM Tractor of the idle speed adjustment screw on the IH carburetor, it is at the top area of the carb, on the engine side of the carb. It should have a spring on it.