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Testing Governor Function

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Engine is a 326431 Briggs 16hp horizontal.  Over the winter I replaced carb, because the loader tractor the engine is on never would run without choke.


Now it wants to overspeed, have to shut it off to keep from blowing up.

Anything I could have done, putting the carb on to make the governor not work?

Then I did not mess with the arm adjustment.


When the engine is running the governor arm should drop down from the at rest position, right?

If I disconnect the linkage from carb throttle plate to governor I should see arm movement when I vary the  throttle plate ?

Is there a way to test the function without opening up the engine by pulling it then yanking off the pan?



I have watched Zippo's video, and read a bunch of manuals, but there seems to be differences in direction of adjustment



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I would guess that when you put the carb back on, you have the linkage hooked up incorrectly.  Most carbs have more than one hole for the linkage to hook into.  Also, it is easy to get something binding or hanging up.  I would doubt if it is the governor if it didn't overspeed before you took the carb off.  Zippo's video on governor adjustment should be simple and correct, if you would want to check that.  Also, I think there is a link to the procedure somewhere here on the site, but don't know where it is right off hand.  I would check that everything moves freely first, then carefully look over how the linkage is hooked up and see if a mistake was made in reattaching the carb.



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The gospel per AL Eden:

"The easiest way to do the static adjustment on a governor follows.
In the Briggs factory school they said just throw away all the stuff about clockwise and counter clock wise. With the engine not running, just take the governor arm and move it so it opens the carb wide open. Hold the arm there with the carb open against its stop. Loosen the shaft on the arm and turn the governor shaft in the arm in the same direction the governor arm went to open the carb up. Turn it until there is no slack in the shaft and with the carb still wide open lock the arm on the shaft. If the engine was just rebuilt was the old governor used. Was the gear white, tan or brown. If it was white or light tan probably OK. Dark brown has been overheated and should not be reused. It is not unheard of for these governors to fail, or if the gear is dark brown the gear to break. Unfortunately this is the very first part put in the block in assembly and it will require the removal of the piston, crank and camshaft. Hope it is just the shaft slipped on the shaft or something simple like that. Good Luck, Al Eden"  I did a look up at the old site and used governor adjustment . I did a copy and paste and the highlighted words  followed me over. :-)

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Yup, good description.  I was always told "everything towards full throttle".  I also agree - not likely the governor broke while the engine was off.  The other thing a lot of people don't realize is that I can walk up to your running engine and snip off your governor spring.  The only thing that will happen is the engine will drop down to an idle.  It is a balancing act between the governor trying to bring the engine RPM down, and the throttle spring trying to open the throttle up.

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The linkage is hooked up the same as the other 6 or so Briggs singles I have here.  Only one hole at the throttle shaft, and only one hole at the end of the governor arm.


Bob thanks for the paste.


I'll play with it some more, but it is difficult to get in there with the loader subframe, cylinder ,and lift arm all in the way.  And then there is the support post for the stack muffler also.

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Today I reinstalled the carb without the rod from the governor to the carb.


Started it and watched the governor arm, as I manually increased the RPM twisting the throttle shaft.

The governor arm never twitched wah

My thought is the centrifugal weights should have made it move as I changed the RPMs,  right?


Looks like engine apart time.............................. unless someone has a better idea !!


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Maybe going over the same things again, but just to be sure, is the throttle arm in the same position on the new carb as the old?

Some point forward on the tractor and some point toward the rear.

Very easy to miss, since there is only one way to hook the linkage


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There is currently no connection between the carb throttle shaft and the governor arm.

The natural position of the throttle is closed.

When I increased the engine RPM the governor arm did not move.


My thought is that means the centrifugal  weights are not moving the governor shaft like they should.


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