# Runs great except when the governor is controlling, then surges hunts dies



## oldcman (Jan 5, 2015)

Need help. Trying to get my Tecumseh engine running properly. First of all, I bought an aftermarket new carb.

If I control the throttle with my fingers, it runs great. If, the governor is controlling, it starts to hunt, then usually goes to fulll throttle and dies.

Idles great.

Not sure what to do, I took the new carb apart to clean it and blow it out with air just in case.

Could the aftermarket carb be too big? At 3500 rpm, the butterfly is barely open. If I have it at 3500 rpm and change the idle mixture screw, it will affect the engine speed. 

Is the carb in some kind of no-man's land... half way in-between idle and full throttle?


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## Normex (Feb 21, 2014)

oldcman said:


> Need help. Trying to get my Tecumseh engine running properly. First of all, I bought an aftermarket new carb.
> 
> If I control the throttle with my fingers, it runs great. If, the governor is controlling, it starts to hunt, then usually goes to fulll throttle and dies.
> 
> ...


 You should post more info like the model of your Tecumseh engine and the more the better.


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## Pathfinder13 (Feb 28, 2014)

You sure you have all the little wires that control it in the proper holes ? maybe one is misplaced ? Just thinking I saw Doneyboy73 on youtube and he had a video on this, you may want to watch that he's pretty good at explaining. Just google "Doneyboy73 adjust governor"


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## motorhead64 (Dec 15, 2013)

Sounds like your governor is not properly set. The governor should not be "controlling" unless your engine is under load. When under load, your engine slows, causing your governor arm to exert force on the throttle to accelerate it to its wide open throttle rpm.
At wide open throttle, with no load, your engine should be at 3600 rpm. The screw to up your rpm is on the throttle, not the carburetor body. Make sure your no load rpm does not exceed 3600 or your engine will over speed and likely grenade. MH


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## classiccat (Mar 1, 2014)

The governor spool should be fully extended causing the butterfly to be almost completely closed at no load. This is normal. When you hit a load, the cam slows and the throttle opens (gov spring keeps the inner gov arm against the spool) to compensate.

And its because of this nearly closed throttle position at no-load high-speed that the idle jet setting is in play.

When its surging, is the air intake spitting fuel?

If so, I would start by leaning out the main jet a bit (turning in) and making the idle jet a tiny bit richer (slightly more open).


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## classiccat (Mar 1, 2014)

Oh...and +1 what motorhead said....replying on my phone and missed the other replies


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## oldcman (Jan 5, 2015)

Here is what I did originally to set the governor. Maybe somebody will see where I went wrong.

With the engine off:
1. Loosen clamp screw
2. Rotate clamp clockwise as far as it will go and hold it.
3. Rotate governor arm clockwise as far as it will go (butterfly WOT) and hold it.
4. Tighten down the clamp screw.

With the engine running:
1. Check rpm, it is reading 3000.
2. Shut off engine. Move spring up one hole. Start engine, rpm increases to about 3300.
3. Tighten throttle screw to fine tune rpm up to 3500.

As for the hunting/surging. Yes, there is fuel spitting out sometimes. When the engine is dying, the rpms slow down, butterly goes full open which kills it further. I can move the butterfly with my fingers back to about 1/4 open which stabilizes the engine at the proper rpm, then if I let go, the governor starts going back and forth until the engine starts to die and the butterfly will go full open which makes it worse and kills it.


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## suspicionofignorance2 (Jan 26, 2014)

Wondering if you can take a pic of it...?


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## classiccat (Mar 1, 2014)

I think we are almost there oldc!

Sounds like she's running too rich. I bet if we leaned out that main jet (bowl), you'll have this bad boy dialed in. I bet it barfs and blows a cloud of smoke when you move the throttle control from idle to fast.


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## oldcman (Jan 5, 2015)

classiccat said:


> I think we are almost there oldc!
> 
> Sounds like she's running too rich. I bet if we leaned out that main jet (bowl), you'll have this bad boy dialed in. I bet it barfs and blows a cloud of smoke when you move the throttle control from idle to fast.


Can't lean it out any more, even all the way lean it still does this. Maybe this is a problem with the aftermarket carb?

I looked at a video on youtube that said to adjust the governor speed by adjusting the angle of the governor arm and clamp but this seems to conflict with other things I am reading.


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## classiccat (Mar 1, 2014)

oldcman said:


> Can't lean it out any more, even all the way lean it still does this. Maybe this is a problem with the aftermarket carb?
> 
> I looked at a video on youtube that said to adjust the governor speed by adjusting the angle of the governor arm and clamp but this seems to conflict with other things I am reading.


 I went back and re-read your trials...and you were able to get it to stabilize when holding the carb throttle steady...so you're not choking it out with fuel. 

as MH already suggested, we may have to back and adjust the governor spring...maybe the governor spring has too much tension at this hole position; The setting you're at now was selected based on RPMs with a carb that wasn't dialed-in. Too-much tension will prevent the spool from extending to close the throttle. In other words, the spool is fighting the governor spring...and the spring is winning.

also, as SOI2 recommended, snap a pick of your linkages...maybe something is out of whack there?


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## oldcman (Jan 5, 2015)

Good news:

I worked on it again this morning and it is running at a nice constant 3540 rpm and maintains within about -200rpm when a load is applied. Here is what I did:

1. Set the governor spring in the hole that would give the minimum tension required to open full trottle against the throttle return spring.

2. Adjust the angle of the governor arm and the clamp to ballpark the governor rpm - I got it to about 3300 rpm.

3. Tighten the throttle screw to fine tune and achieve the proper rpm.

4. Adjust main needle mixture.

5. Readjust the fine adjustment screw for rpm.

I watched one of Donnieboy's videos and showed that the angle between the governor arm and the clamp is what controls the rpm and that it is not a static adjustment. Seemed to work for me (I hope).


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## classiccat (Mar 1, 2014)

oldcman said:


> Good news:
> 
> I worked on it again this morning and it is running at a nice constant 3540 rpm and maintains within about -200rpm when a load is applied. Here is what I did:
> 
> ...


 That is good news!! Congrats!!!!

It sounds like you’ve got a pretty good handle things!!!

I couldn't find a good donboy video that showed proper governor adjustment...the one I saw, he was firing from the hip  Your procedure in Post #7 is the "proper" way to synchronize the throttle control.

Hey...If it's working for ya, that's tops!!!


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## oldcman (Jan 5, 2015)

classiccat said:


> That is good news!! Congrats!!!!
> 
> It sounds like you’ve got a pretty good handle things!!!
> 
> ...


Here's the one I was talking about: 



 Different linkage configuration but same idea.


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## classiccat (Mar 1, 2014)

Donboy has made some incredible videos! Must see for anyone working on small engines!!! ...unfortunately this isnt one of them IMHO.


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