Engine won't speed up.

[Royalwulff24]

Hey guys, so I got my 59 running, timing, etc, all good, ran it for about an hour, throttle worked fine. That was 3 weeks ago, went out this morning had a heck of a time starting it, got it running, after about five minutes, with choke open I pushed the throttle lever ahead, nothing, pushed it the whole way forward, remained at an idle, it ran for a few more minutes with the throttle in wide open positioning, after a few minutes the engine began to speed up, it revved for about 15-20 seconds and went right back to idle, another minute or two it did it again, back down to idle then it shut off. I spayed the holy heck. Out of the linkage last fall and replaced the spring on the governor, the gov to carb linkage is adjusted according to the manual, but when it is adjusted properly I am so close to being out of adjustment that I can't give it the extra turn to account for wear or it will fall off. I Have a problem but I am stumped at the moment, any advice, as always is appreciated
Thank you

[Stoffregen Motorsports]

Are you sure the throttle shaft on the carb is actually moving? The throttle linkage goes to the governor first and that actuates the carb throttle shaft. Try moving the throttle shaft while it's running and see if that allows it to rev. If it does, then there's a problem with the governor.

[Royalwulff24]

Yes everything seems to be working, when I got it started, with the throttle at full speed, it only idles, as it was idling it does up for a second, then slowed back down. The thing worked fine 2 weeks ago, it revved up and slowed down perfectly. I put a new distributor in it, could I possibly have the timing off ? I turned the motor some when the distributor was out When I had it running, it would only run at full throttle, one notch off full throttle and it shut off. Also, when adjusted according to the manual my yoke on the carb to governor shaft is completely out of adjustment, that doesn't seem right. Just seems odd it worked fine two weeks ago

[inairam]

The first thing to check is if the lever on the governor is actually moving back and forth when you move the throttle. The lever does lock up. I had one break just after I replaced the spring.

The second is the adjustment between the governor and the carb needs to be adjusted per the manual. You may want to do this again.

Can you manually move the rod to the carb and get it to rev up? The shaft in the carb could be frozen.

Also, I have had cotter pins that we too long on the connections to the carb causing hand-ups

In my experience, it is almost never the governor's insides. It is almost always a linkage or adjustment problem

[Don McCombs]

Lube all pivot points in the throttle/governor/carburetor linkage system. Then work them each back and forth with the engine off. You may have to disconnect some of the linkage to do this. Check for a broken external governor spring.

[Dale Finch]

You might also check where the governor rockshaft enters the governor lever. There is a tiny woodruff key there which can wear (or the slot it sits in), causing some "slop", or if sheared, would allow the shaft to slip and not respond to governor commands.
Worth a quick check...any rotation of that shaft should cause the lever to move.

[Stoffregen Motorsports]

You haven't said if the throttle shaft at the carb is actually moving. That would tell us a lot about what's going on.

Second, you had the distributor out? Yeah, timing that's far off can cause it to not rev.

Last, have you tried running it without the air cleaner hooked up to the carb? There might be an obstruction inside the filter housing or in the tube itself. With the tube off the intake of the carb, look inside the carb throat and see if the butterfly is moving when you actuate the throttle.

[Eugene]

Lube all pivot points in the throttle/governor/carburetor linkage system. Then work them each back and forth with the engine off. You may have to disconnect some of the linkage to do this. Check for a broken external governor spring.

Spray solvent where the shaft to the carb linkage exits the governor. Then gently work the shaft back and forth, more solvent. Frequently gummed up at that location.

[SamsFarm]

Did one of the pins fall out in the linkage anywhere?

Did it ran ok before you adjusted the linkage?

Have you manually tried to throttle it up at the carburator while it was running?

Doing that you can feel the governor try to override your hand pulling on link arm on the carburator.

[Royalwulff24]

Thank you, I got it. The throttle was sticking and only half open. Thanks again, I never fail to learn something new
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[Matt Kirsch]

For future reference, it's okay to get off the tractor while it is running to inspect the throttle linkage. Give it a tug and see if it is moving. The tractor should rev up by pulling on the rod. That will prove to you that the engine is capable of higher RPMs, and it's not something like the carburetor or distributor that is causing the issue.

Obviously make sure it's not in gear and there are no curious hands around that might somehow slip it into gear.

[Stoffregen Motorsports]

Thank you, I got it. The throttle was sticking and only half open. Thanks again, I never fail to learn something new
,

Nice work.

Curious - where was it sticking?