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throttle adjustment

Sun Oct 14, 2012 4:56 pm

I recently rebuilt a leaking carburetor (successful), but now I can't get the throttle adjusted. I've tried adjusting the idle screws on the carburetor, and also adjusting the linkage between the governor rockshaft and carburetor per the manual.

The tractor is at one RPM only, nearly full RPM's, with no control what so ever with the throttle rod. Please give suggestions as to my next step.

Thanks,

Todd

Re: throttle adjustment

Sun Oct 14, 2012 5:06 pm

Todd, sounds like you may have an issue with the governor. If you have made all the proper connections at the carburetor with the control rod, etc. I would be looking further back on the line of things that can go wrong. Is the key way on the governor output shaft worn?

Re: throttle adjustment

Sun Oct 14, 2012 5:10 pm

Although it's unlikely, check to make sure you don't have the throttle rod and choke rod reversed.

Re: throttle adjustment

Sun Oct 14, 2012 5:17 pm

Don McCombs wrote:Although it's unlikely, check to make sure you don't have the throttle rod and choke rod reversed.
My first thought. Throttle and choke rods mixed up at carburetor.

Re: throttle adjustment

Tue Oct 16, 2012 1:31 pm

Is the Woodruff key to the governor missing?

Re: throttle adjustment

Tue Oct 16, 2012 4:57 pm

Do this simple troubleshooting step:

Engine off, speed control all the way to the rear, curb idle position. Grasp the lever on the carb side of the tractor that is connected to the governor rockshaft and linked to the carb throttle plate. You should realize no movement in either direction.

Advance the speed control all the way forward to fast idle. Again, no movement in either the forward or backward direction should be realized.

Lastly, move the speed control lever to the center of its travel. Grasp the rockshaft lever and this time you should be able to move the lever forward closing the throttle plate.

When testing the lever for movement, don't do it with brute force, just attempt to move it gently, you will overcome the governor spring if you crank on it too hard defeating the purpose of this test.

If in either speed control lever position of fully forward or fully backward you are able to move the rockshaft, expect to find damaged or worn governor shaft linkage components.

Re: throttle adjustment

Tue Oct 16, 2012 7:13 pm

Thanks for the responses and the governor does need to be looked at sometime given that it is very slow to respond. The above fix was a simple adjustment of the idle screw on the front of the carburetor.

Todd
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