# can't tune this briggs engine



## Mistyreiny (Mar 1, 2011)

I recently found an old Briggs and Stratton engine in the barn. I know that it ran when it was pulled off the heavy machinery, although I have no idea what machinery it did come off of.
The only information that i have of this engine is the information stamped on the side:
hp: 11 synchrono balanced
I//C: Industrial/Commercial Engine
Cast Iron Bore
no pull-start, electric only

The engine starts up pretty well, but once it starts it becomes absolutely uncontrollable. The engine constantly over-revs. Usually from the moment it starts up, it hits full throttle within seconds, without touching the throttle.
Also, the tuning is absolutely wrong, as I have 'adjusted' it, with no idea how to correctly do it.
I also have no manual.

If you need anything to help, just ask and I will try to get it.


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## jrrdw (Jun 26, 2010)

Engine numbers stamped in the housing near the spark plug. Do not run it over reving, it will blow up. Is it a horizontal crankshaft shaft or vertical crankshaft? You said it has a throttle on it? 

Does that mean a controller mounted on the housing or your just looking at the linkage? If it's reving high that means the governor isn't taking over as it should. Some engines have a throttle adjusting nut, depends on what it's used for...

Post some pictures of the things you mentioned so we can see what your working with.


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## Mistyreiny (Mar 1, 2011)

Horizontal shaft
here are the pictures that I have of it. I might be able to take pictures of the linkage and carb, but i have to remove the engine first.


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## jrrdw (Jun 26, 2010)

With that hose behind it (if it's attached to the unit) looks like it's bolted to a water pump 'trash pump'. In witch case it should have a fixed throttle, never the less the governor should still keep the throttle under control. This engine should be running at a fixed 3600 RPM's wide open.

Yea pictures of the carburator and linkages from all angles would be helpful.


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## kbowley (Sep 23, 2009)

Check spring on the arm the runs from the governor to the carburetors throttle, it may have come off. Alternately, the governor gear may be broken internally, these engines used a nylon governor gear and they sometimes, although rarely, failed.


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## Mistyreiny (Mar 1, 2011)

Heres a few pictures of the carb and a side shot


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## Mistyreiny (Mar 1, 2011)

more pictures


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## Mistyreiny (Mar 1, 2011)

more pics


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## K-B (Oct 24, 2005)

Looks pretty screwed up. The governor linkage is definitely not stock. I would probably start by replacing the linkages with OEM parts.


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## Mistyreiny (Mar 1, 2011)

if you are referring to the very last picture I posted, the only linkage on the engine is thinner of the two bars with a skinny rod at the end that shoots straight up into the idle adjustment I think it is, about a half long with a screw and a spring on it.
I did however weld that thicker piece on in the picture so that i could attach my own linkage on it, whereas my linkage would be mounted from below the picture.


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## jrrdw (Jun 26, 2010)

That is a down draft carburator. The choke is the lever in between the air cleaner mount and carburator, where the screw clamp is that's the throttle shaft. It looks like it needs a good cleaning to a down right rebuild. Do you still have the air cleaner and housing? 

Cut what you welded back off it will only cause you more problems in the long run. That thin wire running up to the 'idle adjustment' is in fact the governor linkage. The piece it hooks up to is the throttle valve and the little screw with a spring is the fast idle adjustment screw. 

Unscrew the fast idle screw until there is a little free play in the linkage coming from the governor arm then restart the engine and the governor should take over not allowing the engine to be held wide open by the fast idle screw.

I see no remote or fixed throttle on this engine. If you wish to add either you will have to add some more parts, cable mount/lock, more linkage and another spring. You will need the engine numbers that are stamped on the fly wheel cover by the spark plug. If you can't see them squirt a little WD-40 on the cover and they will be easy to see.


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## kbowley (Sep 23, 2009)

Hi,
With the current linkage you have, the governor cannot work properly. As R-D. Misty and jttdw all explained to you, there is no way for the govenor to function. First things first, to have the governor function properly, loosen the locking bolt that holds the governor to the shaft coming out of the engine. Next, hold the brass governor shaft with a pair of pliers and turn the shaft clockwise as far as it will turn. then pull the linkage arm down as far as it will go AFTER you back the idle adjustment screw counter clockwise until the throttle plate is completely closed in the carburetor. So, 1.) back the idle stop screw out until the throttle plate can full close. 2.) Loosen the bolt/nut that holds the governor to the brass shaft coming out of the engine. 3.) use a pair of pliers to grasp the brass shaft and turn it fully clockwise until it stops. 4.) Pull the linkage arm you made away from the carburetor as far as it will go. 5.) Tighten the linkiage to the brass shaft. 
You can then turn the idle screw inward until the throttle barely begins to open and the engine should run at idle speed. If you wish to have control of the engine speed, you will need a spring with the proper tension load pulling the linkage upward via another linkage that is movable so that when you wish to increase the engine speed, the spring will pull upwards on the current linkage arm so that it opens the throttle plate via the spring. you cannot hook a cable or rod directly to the current linkage and have the governor function as it should, the linkage must be pulled via a properly tensioned spring.



I suggest acquiring the proper engine manual so you understand how the governor works and the proper way it should be set up on your engine. It is best to purchase the correct governor spring for your engine direct from Briggs or a Briggs dealer as each governor is weighted differently. It will not function correctly with the current linkage.


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