Mower RPM - Governor or Carburator?

NJDan

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When I start my Honda mower it revs like crazy to about 6000 rpm (3100 recommended max setting). I don't let it do that for very long. Prior to this I had to take my engine apart to fix a connecting rod problem but I never made any adjustments to the governor. I also did not take the carb apart and try to clean it. It seems to me there is a governor problem somehow but before I tear the engine apart again I wanted to rule out anything else. Is it possible that the carb could be causing the high revs and not the governor? I don't believe there is an idle adjustment on this carb. It's an HRX217K4HZA. Any suggestions?
 

sgkent

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the speed of these small engines is normally regulated by a governor. Some use a vane that moves in the breeze from the flywheel and some use a gear assembly. Maybe some late FI ones use electronics. I'd be looking at how you hooked the governor back up.

maybe #7 is the assembly in the engine. Then there are some rods that relay to the carb. At lease this is the pictorial that comes up online for that mower. https://www.hondapartsnation.com/oemparts/a/hpe/505ce4a5f870022d24bdc70e/oil-pan
 
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bertsmobile1

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First guess is when you replaced the sump you have not captured the governor or while apart the bob weights got out of place
 

NJDan

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the speed of these small engines is normally regulated by a governor. Some use a vane that moves in the breeze from the flywheel and some use a gear assembly. Maybe some late FI ones use electronics. I'd be looking at how you hooked the governor back up.

maybe #7 is the assembly in the engine. Then there are some rods that relay to the carb. At lease this is the pictorial that comes up online for that mower. https://www.hondapartsnation.com/oemparts/a/hpe/505ce4a5f870022d24bdc70e/oil-pan
Yes, that is the correct drawing. There is a gear that meshes with the gear on the crankshaft. This spins two weights that raise and lower the pin that pushes on the governor "paddle" that is connected to the governor arm outside of the engine.
 

NJDan

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First guess is when you replaced the sump you have not captured the governor or while apart the bob weights got out of place
That's what i'm trying to confirm by process of elimination. I was worried about the governor because you can't see it to confirm that the gears mesh, but then you can't get the cover back on unless they do. I can't specifically recall where the paddle arm or pin was when I put everything back together. If the carb cannot be the cause of this and the linkage between the governor arm and the carb is normal then it has to be the governor, right?
 
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NJDan

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Yes, that is the correct drawing. There is a gear that meshes with the gear on the crankshaft. This spins two weights that raise and lower the pin that pushes on the governor "paddle" that is connected to the governor arm outside of the engine.
Another comment on that drawing. Item 12 the governor arm shaft actually has to be turned up 90 degrees so that the flat end rests against item 11, the governor slider, right? I can't be 100% sure that I checked this but I can't imagine that I didn't. I might be able to confirm this because there looks like there is a groove on the end of the shaft that you can grab with pliers and turn if needed. I don't think I see that groove on mine, which means it might be facing down making it hard to see. I need to look at that when I get home. That might be the confirmation that I need.
 

bertsmobile1

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When you refit the governor you must make sure that the shaft , part # 12 is touching the slider , part 11 and the slider itself is engaged with the bob weights
They can be a little tricky .
To confirm the governor is not working start the engine then manually work the governor arm
As you speed up the engine you should feel the governor pulling against your finger and the faster the engine runs he harder the governor should push.
It is easy for the shaft to end up in the wrong place , 180 deg out so it is not touching the slider
Bad news is that usually causes the slider to fall off so it is back into the engine again .
 

NJDan

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When you refit the governor you must make sure that the shaft , part # 12 is touching the slider , part 11 and the slider itself is engaged with the bob weights
They can be a little tricky .
To confirm the governor is not working start the engine then manually work the governor arm
As you speed up the engine you should feel the governor pulling against your finger and the faster the engine runs he harder the governor should push.
It is easy for the shaft to end up in the wrong place , 180 deg out so it is not touching the slider
Bad news is that usually causes the slider to fall off so it is back into the engine again .
So I just looked at that part 12 and there is no groove on it to get a pliers on. It is just a round pin so I can't confirm that it is in wrong. However, your comment about resistance is helpful. When I have the mower on full throttle and the speed spring is tight the governor arm is vertical and in its most clockwise position. When I throttle down and release tension from the speed spring the governor arm is supposed to turn counterclockwise and slow the engine. In my case this doesn't happen. I actually made a video on this but nobody replied. If I take what you are saying correctly then the governor should be providing the force needed to move the governor arm when throttle is reduced (when it is running, of course). The spring on the linkage to between the governor arm and the carb is probably there only to keep the linkage from being loose and has nothing to do with pulling the governor arm. Here is the video:

 

lefty2cox

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Correct. That spring just takes slop out of the linkage from what I understand. I agree with Bert. She's coming apart again. Don't feel bad. It's a right of passage. I know I've been there. Look on the bright side...you already know how to do it so it should go a lot quicker this time.
 

NJDan

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Correct. That spring just takes slop out of the linkage from what I understand. I agree with Bert. She's coming apart again. Don't feel bad. It's a right of passage. I know I've been there. Look on the bright side...you already know how to do it so it should go a lot quicker this time.
LOL. Thanks for the encouragement. I don't mind redoing it. What I mind is if I redo it and then somebody says, "Oh, that's not the governor. It's just xyz problem with the carb. But, yes, I can tear this thing down in no time at all now! I'm going to take a photo of what I find in there. I better not find a perfectly functioning governor! The more I understand the more it looks pretty clear.
 
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