B&S 20hp (331777-2372-G5) runs wide open after you start it?

[Bat57]

By front I do hope you mean closest to the engine which most would call rear

Yes it is the one closest to the engine.

 

[Bat57]

Can you move the governor rod to carb freely or it is hard to move. If it is stiff and won the move the carb linkage it is wrong. I have seen the governors make spiral like a bolt on the shaft they are on if so that part is made into the block and not replaceable and new a new motor. Check the linkage first and if not moving free you have it adjusted wrong and if it does move free then it is internal under the governor.

Thanks, have done all that and everything moving freely and working like it is suppose too.

 

[cruzenmike]

I had this exact same issue and I replaced the governor and it fixed the problem. When doing both the static and dynamic governor adjustments on the linkages, you have to be certain that you are turning the governor shaft the correct direction. If not you will end up allowing the engine to race up. I am not sure if you are referencing a service manual for your exact engine, but be sure to check this all out. When I took my crankcase off of my engine I found the governor in pieces.

Here is a link to my post a couple of years back when I was having this problem. A great guy on here provided me with the service manual from Briggs and I was able to properly adjust the governor.

44M777 24hp ELS Revving Uncontrollably

Hello. I was experiencing some hunting/surging on my Briggs v-twin so I attempted to adjust the governor. Now when I start the mower, it revs uncontrollably. It is revving so high the engine is going to explode! I have tried over and over to adjust the governor but nothing I do fixes the...

www.lawnmowerforum.com

 

[Bat57]

I had this exact same issue and I replaced the governor and it fixed the problem. When doing both the static and dynamic governor adjustments on the linkages, you have to be certain that you are turning the governor shaft the correct direction. If not you will end up allowing the engine to race up. I am not sure if you are referencing a service manual for your exact engine, but be sure to check this all out. When I took my crankcase off of my engine I found the governor in pieces.

Here is a link to my post a couple of years back when I was having this problem. A great guy on here provided me with the service manual from Briggs and I was able to properly adjust the governor.

44M777 24hp ELS Revving Uncontrollably

Hello. I was experiencing some hunting/surging on my Briggs v-twin so I attempted to adjust the governor. Now when I start the mower, it revs uncontrollably. It is revving so high the engine is going to explode! I have tried over and over to adjust the governor but nothing I do fixes the...

www.lawnmowerforum.com

 

[Bat57]

I had this exact same issue and I replaced the governor and it fixed the problem. When doing both the static and dynamic governor adjustments on the linkages, you have to be certain that you are turning the governor shaft the correct direction. If not you will end up allowing the engine to race up. I am not sure if you are referencing a service manual for your exact engine, but be sure to check this all out. When I took my crankcase off of my engine I found the governor in pieces.

Here is a link to my post a couple of years back when I was having this problem. A great guy on here provided me with the service manual from Briggs and I was able to properly adjust the governor.

44M777 24hp ELS Revving Uncontrollably

Hello. I was experiencing some hunting/surging on my Briggs v-twin so I attempted to adjust the governor. Now when I start the mower, it revs uncontrollably. It is revving so high the engine is going to explode! I have tried over and over to adjust the governor but nothing I do fixes the...

www.lawnmowerforum.com

Sorry, accidently hit the post button before I typed anything. I replaced the camshaft due to broken compression release valve. Put new one in and checked governor and nothing wrong with it. Reassembled the engine, cleaned and reinstalled the carburetor assembly, hooked all the linkage back up and double checked against manual and another motor from same series. Started motor and it ran at almost full throttle. Shut engine down then loosened nut on governor arm and pulled the throttle all the way open then turned governor shaft until it touched the governor, retightened arm nut. Started engine again, same outcome, almost full throttle and couldn't control with lever. Broke engine apart and installed new governor. Put everything back together, double checked all linkage, did arm adjustment again. Started engine and same exact thing happening again. Engine running at almost full throttle. Thanks for your help.

 

[cruzenmike]

It sounds like you have everything covered, but it is possible that you missed something. Did you by chance replace the governor springs and are they in the correct slots on the governor linkage? These springs can become stretched and result in surging or excessive revving. If I remember correctly, my governor linkage had 2-3 springs and had to be set up just right to ensure that it work properly.

In the end, if you are 100% sure that the governor is not to blame for the problem, then you might want to look at completely rebuilding the carburetor. There is a point where ethanol does damage to rubber o-rings within the carb that cannot be resolved with a simple cleaning. On my ELS I had to remove the two jets and replace the o-rings around them because it was surging. A more catastrophic failure of the carb might lead to excess fuel getting in.

One last thing to look at, in the manual that is linked in my post, look at the adjustment for the RPM. You will need to have a tiny tach or similar. Start with setting the minimum no load RPM. Then you can do a top no load RPM. Of course be careful. If the engine is really racing, you do not want to do this or mess with the governor linkages while it is running at excessive speeds. You can find out your exact RPMs for your engine code by reaching out to your dealer or posting on this site. There are a few Briggs techs who can give you the information that you need.

 

[StarTech]

It sounds like you have everything covered, but it is possible that you missed something. Did you by chance replace the governor springs and are they in the correct slots on the governor linkage? These springs can become stretched and result in surging or excessive revving.

You misunderstand the purpose governor springs. When stretched they do not causing over revving; surging maybe if the spring rates are wrong but just lower than normal governed speed most times. Governor springs pulls the throttle to full speed and then either the pneumatic, air vane, or mechanical governor pushes to slow the engine speed back toward idle speed not the other way around until things balances out.

 

[Bat57]

It sounds like you have everything covered, but it is possible that you missed something. Did you by chance replace the governor springs and are they in the correct slots on the governor linkage? These springs can become stretched and result in surging or excessive revving. If I remember correctly, my governor linkage had 2-3 springs and had to be set up just right to ensure that it work properly.

In the end, if you are 100% sure that the governor is not to blame for the problem, then you might want to look at completely rebuilding the carburetor. There is a point where ethanol does damage to rubber o-rings within the carb that cannot be resolved with a simple cleaning. On my ELS I had to remove the two jets and replace the o-rings around them because it was surging. A more catastrophic failure of the carb might lead to excess fuel getting in.

One last thing to look at, in the manual that is linked in my post, look at the adjustment for the RPM. You will need to have a tiny tach or similar. Start with setting the minimum no load RPM. Then you can do a top no load RPM. Of course be careful. If the engine is really racing, you do not want to do this or mess with the governor linkages while it is running at excessive speeds. You can find out your exact RPMs for your engine code by reaching out to your dealer or posting on this site. There are a few Briggs techs who can give you the information that you need.

Thanks for the info. Will check everything again with new info.

 

[cruzenmike]

You misunderstand the purpose governor springs. When stretched they do not causing over revving; surging maybe if the spring rates are wrong but just lower than normal governed speed most times. Governor springs pulls the throttle to full speed and then either the pneumatic, air vane, or mechanical governor pushes to slow the engine speed back toward idle speed not the other way around until things balances out.

So based upon what you are saying, it HAS to be the governor that is set up incorrectly on the OPs engine. I could not recall whether or not the governor had a natural tendency to open or close the carb via the linkages. Only makes sense, that like in air brakes, the configuration would be to the safest "condition" and in this case it would be the minimum no load RPM.

When adjusting my governor I had made the mistake of turning the governor shaft the wrong way and securing it which did not allow for it to operate properly. The OP should try doing the opposite of what he has tried already and see if the issue resolves. I could be wrong (again) but different engines might have different governor setups?

 

[Bat57]

So based upon what you are saying, it HAS to be the governor that is set up incorrectly on the OPs engine. I could not recall whether or not the governor had a natural tendency to open or close the carb via the linkages. Only makes sense, that like in air brakes, the configuration would be to the safest "condition" and in this case it would be the minimum no load RPM.

When adjusting my governor I had made the mistake of turning the governor shaft the wrong way and securing it which did not allow for it to operate properly. The OP should try doing the opposite of what he has tried already and see if the issue resolves. I could be wrong (again) but different engines might have different governor setups?

Thanks, I will recheck this.