Run away engine

Gregyver

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I think I posted something about this a couple weeks ago. On startup after sitting idle for a season this John Deere D140 riding mower with a B&S 24hp motor revved up so high I thought it was going to blow up. The governor went full throttle and would not go to an idle. I took the engine apart and examined the governor but I could not find anything wrong. I re-assembled the engine the engine and started it up but it went right back to full throttle. I checked the governor adjustment and it was correct. Anyone have any ideas as to why this happened?
 

Gregyver

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UNFORTUNATELY THAT IS NOT THE PROBLEM. I WISH IT WERE THAT SIMPLE. GOVERNOR IS ADJUSTED CORRECTLY AND THE LINKAGE IS GOOD AS WELL. ON START UP THIS ENGINE GOES MAX RPM AND STAYS THERE. I'M AT A LOSS TO EXPLAIN IT.
 

ILENGINE

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Have you looked at the throttle plate in the carb. If it came loose and is jammed in the intake will effect throttle control. Other than that it sounds like a failed governor. But an intake air leak between the carb and the head cause also effect engine speed.
 

hlw49

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You need to learn some manners or maybe you don't know that replaying in all caps is consider shouting. Not a good way to get any help.
 

Gregyver

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Have you looked at the throttle plate in the carb. If it came loose and is jammed in the intake will effect throttle control. Other than that it sounds like a failed governor. But an intake air leak between the carb and the head cause also effect engine speed.
I haven't taken the carburetor off yet. I didn't think to look there. Thank you for that. I will definitely look at that this evening. I hope the problem is that! I will keep you posted. Thank you again
 

Tiger Small Engine

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I haven't taken the carburetor off yet. I didn't think to look there. Thank you for that. I will definitely look at that this evening. I hope the problem is that! I will keep you posted. Thank you again
You went to all the work of removing engine, taking engine apart, and checking the governor, and then reinstalling. Something is wrong with the governor if adjusted correctly. Probably means repeated all steps and this time replacing with a new governor assembly.
 

bertsmobile1

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Governors 101
the governor tries to slow down the engine
The faster the engine goes the harder the governor tries to shut the throttle down.
So simple test is to gat some one to start the engine while you hold the governor arm then feel for the governor trying to move against you finger
IF you can easily move in fast & slow with no change is resistance then the governor is shot
If it moves strongly and that movement opens up the throttle then it is connected to the wrong hole on the carb.
 
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