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Paul D.

Engine reving high (Help needed)

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Paul D.

So I was just finishing up mowing the other day and all of a sudden out of now where my motor revs out of control! I dropped the throttle and shut if off but I can't seem to figure out whats going on I checked the governor and it seems to be adjusted correctly. I didn't see anything else glaringly wrong. I normally have a budy that does all my carb. and engine trouble shooting work but he is sidelined right now by medical issues. Anybody got any ideas on what might be going on here? It's a Kohler 14hp on a C 141

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Sparky

I bet your govenor is not fine and thats why its over revving.

Mike...........

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oldredrider

I have GT-14 that did the same thing once. I have rebuilt countless Kohler engines and carbs and still don't know why it happened. Rev limiter is set properly. Hope someone can give us a clue.

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rmaynard

There is a part of the governor called the cross shaft that is inserted as one of the first parts when reassembling the engine. The end of the cross-shaft is what sticks out through the brass bushing nut and the governor arm attaches too. There is a plate riveted to the cross shaft inside the engine that is activated by the pendulums on the governor gear. That part is known to come off. When it does, the governor is no longer functional, and the engine will rev out of control. Unfortunately, the repair requires almost total disassembly of the engine.

The way to find out if this is the problem is to loosen the bolt that secures the governor arm. Rotate the governor shaft counter-clockwise. It should stop. If it doesn't, your cross shaft has come apart.

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oldredrider

I checked the cross shaft when it over revved. Not broken. Only revved high once and has been perfect since.

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Paul D.

So good news I think... I checked and the governer and it does stop when rotated so I assume that the cross shaft is intact. Sooo what do I check next?

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Paul D.

If I drop the throttle it does idle down very nicely but when I raise it back up it revs right back up again

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joel_400

I would check to make sure theres nothing binding that may cause the intermittent problem. I too have had a cross shaft break. You dont absolutely have to take it all apart to replace the cross shaft. With patience, a magnet and a wonderful girlfriend to hold the flashlight it can be done!

Joel

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can whlvr

i would check the throttle stop bracket,maybe it loosened off and is letting her rev up

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Paul D.

I will try to find time to check a few things tomorrow. It's ball season and with 3 kids on 5 teams 3 of which I coach time is kind of at a premium this time of year. I will post my findings as soon as I can. Thanks for all the input!!!

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Cole

i would check the throttle stop bracket,maybe it loosened off and is letting her rev up

yep I would check the throttle stop bracket also, i have (had) the same problem as you yesterday i read this post, looked and my throttle stop bracket wasnt there so i had to fab a new one and now works perfect again this has helped me so far so hopefully it helps you too. :)

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Paul D.

So adjusted the throttle stop bracket, set the governor to original setting and the engine seemed to be reving correctly again. Then I drove forward and I have lose of power. Engage the deck and drive forward and it really struggles to go at all! What am I missing? I am sure it's something stupid but it's kicking my butt :angry-screaming:

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can whlvr

so did you adjust the cross shaft as per manual,loosen the pal nut on the gov arm,turn it all the way away from the carb,then grab the cross shaft end with pliers and turn all the way counterclock wise and retighten palnut then adjust the stop,if this doesnt work then maybe you lost a flyweight on the gear,hope not as this requires complete tear down of the bottom end

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Paul D.

Is there any way to check that without tearing down the motor?

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can whlvr

what do mean,check the gear,or adjust the crosshaft,the cross shaft is an external setting,the gear is way inside above the cam,its the first thing that goes in on a rebuild,but you might see in there with the pan off the bottom,dont know if theres room for a scope through the cam plate and then around the cam to see,matbe someone has done this but for me i would take the oil pan off and see if any meatal parts in there,after i illiminated all other avenues

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sorekiwi

I am thinking that if the flyweights had come apart inside the engine, then it wouldnt have fixed itself and returned to normal behaviour.

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Paul D.

It didn't fix itself. I had to adjust the throttle cable and throttle stop. I guess I am kind of surprised that it didn't bounce around and destroy something else if it came loose

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Rooster

Over revving can also be caused by an extremely lean condition...such as running out of gas.

The big difference, when you run out of gas it revs up then dies, lol!

This will also cause a loss of low end power.

It is possible you have a fuel issue, blocked line or dirty carb.

You are most likely on the right track with the throttle settings, but I also wanted to put that out there as a possibility.

at idle you are manually holding the carb down, as soon as you come off of idle the governor is more in control than you are.

Use the manual and get all of the governor settings correct !

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Anglo Traction

I concur with Rooster, If all the Governor gear is ok and correctly adjusted, look at the Carb.

It only needs a piece of loose junk in the Carb's High Speed Needle or it's housing and the mixture can 'Lean Out' and rev over Max with the Throttle Plate wide open.

Additionally if the Throttle Shaft is worn, it will draw more air in while at Full Throttle and add to the increased engine speed.

If you have the equipment to check your RPM, use it to set your Max rev limit to 3400 until your sure the problem is cured. Then reset to 3500 if you wish.

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Paul D.

Well I've been gone for awhile (life's been getting in the way). I am planning on tearing down the engine this weekend to see what's going on with the governor. If the plate has come loose is there a way to reattach it or do I need to replace it?

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lobo

I just had a govenor gear break, before you tear it all apart you might want to take the welsh plug out and take a look at your govenor gear.

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Paul D.

Well I drained the oil and pulled the pan Friday night. As suspected the governor gear was trashed. Picked one up sat. Afternoon and yesterday we tore the engine down, put in the new gear, reassembled and dropped it back in the tractor. She's running like a top again. With the snowblower installed. Now if we can just get some snow!!!

Thanks for all the input guys!

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gregg'shorses

It's good that you got it repaired before the connecting rod goes through the block . :eek:

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