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How much force to move throttle with engine not running?

Posted: Mon Apr 19, 2021 8:19 am
by TinkerBolt
I'm in the process of rebuilding my first non-running Cub so have no experience with a running run. How much force should it take to move the throttle linkage at the governor? I have the linkage disassembled from the carb but my throttle is very difficult to move one way or the other. I am thinking something is jammed in the governor but wanted to make sure this linkage is not dependent on the engine running. Should the throttle always be able to move back and forth easily or does the engine have to be running? Also, if it should be easy to move the throttle, what are the causes of mine being very difficult? I'm guessing there is something going on inside the governor preventing it from moving easily. Thanks for any advice.

Re: How much force to move throttle with engine not running?

Posted: Mon Apr 19, 2021 8:25 am
by SamsFarm
Moving the throttle lever at the steering wheel support should be relatively easy, and the same whether running or not!

Re: How much force to move throttle with engine not running?

Posted: Mon Apr 19, 2021 8:31 am
by TinkerBolt
Thanks for that confirmation. I just found the article on how to rebuild the governor. I will take it apart and see what be causing the issue.

Re: How much force to move throttle with engine not running?

Posted: Mon Apr 19, 2021 9:04 am
by Dale Finch
Often the problem is the governor lever being "frozen" on the shaft. Spend some time spraying it with some penetrating oil, and try moving it a tiny bit at a time. Be careful, though...avoid hard prying or hitting that lever, as it is easily broken. Patience is the answer!
Here is what it looks like...#11 below:

http://farmallcub.com/rudi_cub/www.cleancomputes.com/Cub/Cub%20Parts%20Manuals/TC-37F%20Revision%206%20(08-79)/Group%20-%2012%20-%20Power%20-%20C-60%20Engine/Page-18.jpg

Re: How much force to move throttle with engine not running?

Posted: Mon Apr 19, 2021 6:21 pm
by Glen
Hi,
The throttle lever on the steering wheel support should move freely when everything is connected normally, especially in the rear half of it's movement. From straight up and forward, it pulls on the governor spring, so it is going to feel harder to move.
The farther ahead, the more tension on the spring.

The lever uses the same amount of effort to move with the engine running, or not running.

It sounds like the governor linkage arm on top of the governor might be partly frozen, from no lube, and hard to move, a common problem with Cubs.
Below is a pic from TM Tractor of the governor, and arm, lube it with penetrating oil where the cotter key is, and at the other end of it, about 1" toward the right side of the Cub.
It may take time to free it up, the arm should turn freely on the shaft, keep lubing it, and working it.
Don't pry on the arm hard, or hammer on it, it can break.
When it is free, oil it with motor oil.
The arm turns on the shaft, the shaft is supposed to be solid on the governor.

There are usually 1 or 2 notches at each end of the quadrant that are not used, the lever won't move into them.
There is a stop bolt on the governor for the high speed, the arm touches the bolt when the throttle lever is ahead to where the high speed is adjusted to.
You didn't say the year of the Cub, the high speed for Cubs before serial number 192113 is 1800 RPM. :)

Re: How much force to move throttle with engine not running?

Posted: Wed Apr 21, 2021 9:31 pm
by cjack
Yes, be careful with the lever on the governor. I can attest to Glen's statement that hammering on it can break it! We did find a steel replacement after a quick search.

Re: How much force to move throttle with engine not running?

Posted: Thu Apr 22, 2021 6:41 am
by inairam
TinkerBolt wrote:Thanks for that confirmation. I just found the article on how to rebuild the governor. I will take it apart and see what be causing the issue.


It is almost never the governor itself. As others have posted it is usually the linkage or the lever or something else. Start by making sure the linkage is free from the lever to the carburetor, and for that matter that the carb is free, to identify the problem area. After you have exhausted all other possibilities then consider the governor itself.

Re: How much force to move throttle with engine not running?

Posted: Thu Apr 22, 2021 10:19 am
by TinkerBolt
Thanks again for all the tips. Generous doses of PB Blaster, WD-40, and lightweight oil freed the lever up after about 24 hours. Operates very smooth now.