422707-121401 sump gasket

Forest#2

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Have you looked at the Briggs and Stratton L-Head OPPOSED TWIN service manual 271172?

You can find one on-line to review the Governor settings and look at carb/gov linkages, adjustments, pg 54-69
 
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McTurff

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The engine speed is controlled by a balancing act between the governor and the governor spring. When the engine is running the governor should pull the carburetor closed, when you start the engine is there any force opposing the sparing? Trying to close the throttle?
Can you hold the governor linkage to idle and does the engine idle down? If so the governor is not working or the wrong spring is on the governor arm.
How are you adjusting the governor (or syching it to the carb)? With the control wide open, the carburetor should be wide open. Note which way the governor shaft turns to open the then throttle. Turn the shaft that direction as far as it will go, now tighten the pinch bolt Governor is now adjusted. Try to move the linkage to idle if it does not move you turned the shaft the wrong way. The linkage should move freely with no rough spots or hang ups.
NOTES. Aproperly adjusted governor should not cause surging. A lean mixture will cause surging. A carburetor cleaning may be needed.
If after properly adjusting the carb and even moving the linkage to idle does not controll the engine speed check the carbfor a loose throttle plate or a broken throttle shaft, or even the control lever loose on the shaft.
When the engine shuts off the governor naturally stops functioning and the arm will pulled to wide open by the spring, on starting the governor starts "working" and overcomes the spring closing the throttle plate to maintain set speed.
Thanks will be going through it again today
Has to be something in the linkages
Hopefully can figure this out!
 

McTurff

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Have you looked at the Briggs and Stratton L-Head OPPOSED TWIN service manual 271172?

You can find one on-line to review the Governor settings and look at carb/gov linkages, adjustments, pg 54-69
Thanks will review again
 

McTurff

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The engine speed is controlled by a balancing act between the governor and the governor spring. When the engine is running the governor should pull the carburetor closed, when you start the engine is there any force opposing the sparing? Trying to close the throttle?
Can you hold the governor linkage to idle and does the engine idle down? If so the governor is not working or the wrong spring is on the governor arm.
How are you adjusting the governor (or syching it to the carb)? With the control wide open, the carburetor should be wide open. Note which way the governor shaft turns to open the then throttle. Turn the shaft that direction as far as it will go, now tighten the pinch bolt Governor is now adjusted. Try to move the linkage to idle if it does not move you turned the shaft the wrong way. The linkage should move freely with no rough spots or hang ups.
NOTES. Aproperly adjusted governor should not cause surging. A lean mixture will cause surging. A carburetor cleaning may be needed.
If after properly adjusting the carb and even moving the linkage to idle does not controll the engine speed check the carbfor a loose throttle plate or a broken throttle shaft, or even the control lever loose on the shaft.
When the engine shuts off the governor naturally stops functioning and the arm will pulled to wide open by the spring, on starting the governor starts "working" and overcomes the spring closing the throttle plate to maintain set speed.
Everything you mentioned i have done
All springs in place ect
The original carb is fine and put new one on to test that way!
The engine was opened as my earlier post indicated to find governor in tact!
The governor spring pulls trottle plate to wide open!
Today I put a wire on governor arm to control it and bring it to idle
And I can so I'm stumped because when I opened engine as stated in earlier post the governor gear inside was in perfect condition???
I did not touch gear or move anything inside engine when opened so I'm wondering is something with governor still has a problem inside!
 

bentrim

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You stated you were able to bring it back to idle by using a wire -- does the governor are try to pull it back to idle? If not there could be one of two issues. Governor not adjusted properly which you said you did, or the internal governor has a problem which could be 1. the flyweights weights are missing or not moving properly 2. the thimble is worn or stuck on the shaft possiblely it is worn where the weights push against it not allowing it to function properly. 3. The shaft has pulled out of the case and will not allow the weights/thimble to collapse fully. 4 The governor arm is bent and not contacting the thimlbe.
If the governor arm has force trying to pull it back. then check the governor spring is it or they hooked up correctly.
To check for this issue remove the springs from the governor arm and start engine it shoul immediately go to idle and you would have to force the lever to speed up engine, just as the spring would do. If you have no force trying to move the lever back to idle ---- well just may be time for surgery -- again.
 

McTurff

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You stated you were able to bring it back to idle by using a wire -- does the governor are try to pull it back to idle? If not there could be one of two issues. Governor not adjusted properly which you said you did, or the internal governor has a problem which could be 1. the flyweights weights are missing or not moving properly 2. the thimble is worn or stuck on the shaft possiblely it is worn where the weights push against it not allowing it to function properly. 3. The shaft has pulled out of the case and will not allow the weights/thimble to collapse fully. 4 The governor arm is bent and not contacting the thimlbe.
If the governor arm has force trying to pull it back. then check the governor spring is it or they hooked up correctly.
To check for this issue remove the springs from the governor arm and start engine it shoul immediately go to idle and you would have to force the lever to speed up engine, just as the spring would do. If you have no force trying to move the lever back to idle ---- well just may be time for surgery -- again.
So i was using wire to pull governor arm to idle so I guess I was doing what governor is supposed to do?
Ok all good suggestions
Can't be adjustment I've tried every which way to Sunday!
Will try the spring removal test!
 
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McTurff

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Ok all good suggestions
Can't be adjustment I've tried every which way to Sunday!
Will try the spring removal test!
One more thing
Should the manual throttle control from dash or console move the throttle plate from closed to open 🤔
I asked this question before my OHV engines do this one is not?
Or is the throttle plate always held open by governor arm and spring weather in Turtle 🐢 or rabbit 🐇???
This one is not functioning correctly if that's the case and would be linkage??
 

bentrim

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Some engines do this but I am not familiar (don't remember really) it has been a while since I have worked at one of the opposed flat head twins.
The best would be to follow the linkage and see if there is a link or lever to do so. Even the service manual has no clear picture of the control.
If interested in the repair manual it is PN 271172 printed 4/99 -- The black book the early manual was red.

WARNING: BEFORE STARTING or running
engine, static adjustment of the governor must
be completed! Failure to make the static
adjustments first could result in engine overspeeding
which may result in engine damage,
property damage or personal injury.
STATIC GOVERNOR ADJUSTMENT
1. With governor lever nut loose, push governor lever
counter-clockwise as far as it will go (wide open
throttle) and hold in this position.
2. Rotate governor shaft counter-clockwise as far it
will go, Fig. 25.
Torque governor nut to 100 in. lbs. (11.0 Nm). A 7/16”
crowfoot socket may be required on ducted engines.
See procedure below for dual speed or 1800 RPM
generators. Fig. 25 – Static Governor Adjustment

Governor Gear
1. Check gear for damaged or worn teeth, Fig. 11.
2. Check thrust washer, governor weights and hinge
pins for wear and burrs.
3. Check governor cup for wear and burrs.
Replace as required.


Governed Idle
All Twin II twin cylinder engines equipped for remote control are equipped with governed idle. A detent in the equipment
control provides governed idle when the equipment control is moved to the full slow position.
Pre-Twin II, twin cylinder engines equipped for remote control have provision for governed idle. Equipment manufacturer’s
control may or may not provide a detent for governed idle. Controls with detents permit the governor to maintain
engine speeds under light loads with control in the detent position. Moving the remote control beyond the detent to the
full slow position overrides the governed idle and closes the throttle to the fully closed position to prevent engine overspeeding,
in the event of governor failure.
Remote controls without detents will provide governor control, depending on control setting, at all positions except full
slow position.

General Information
The purpose of the governor is to maintain, within certain limits, a desired engine speed, even though loads may vary.
The governor spring tends to pull the throttle open. The force of the counterweights, which are operated by centrifugal
force, tends to close the throttle. The engine speed at which these two forces balance is called the governed speed.
To comply with specific top governed speed limits, Briggs & Stratton supplies manufacturers with engines having an
adjustable top speed limit, which is set to equipment manufacturers’ specifications.
If a governor spring must be replaced, consult the appropriate Illustrated Parts Lists. Choose the proper governor springs
by engine type number.
 

McTurff

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I hope someone that has this engine chimes in on this before I open this thing up again!
Manual doesn't explain this and I can't find a video showing the console movement in relation to throttle control opening and closing throttle plate
I can see how it would work but just seems that its not designed to function this way and that the throttle plate is always WOT plate unit engine starts and governor closes it???
 

Forest#2

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With the engine not running.
I looked a couple of my opposed twins full open throttle and full closed throttle.

full open throttle on the dash = (can feel the throttle lever shaft at the carb slightly forceful spring loaded to full open and some force required to force it too go to the idle position and will spring back full open when not held at idle.

As the throttle on the dash is moved from full open to full closed towards idle the carb shaft moves less than half way closed towards idle and is only slightly (very weak) spring loaded when at idle position.
Carb shaft just very slightly spring loaded. (not hardly any governor spring tension felt with throttle on dash at idle)

I suspect your throttle control plate or governor springs are not connected correctly or someone has installed wrong length connecting links.
You might have to remove the throttle plate from the engine and look behind at the springs or go to ebay and search opposed twin throttle plate and linkages, look at some pictures. I think maybe you could completely remove the little governor spring and your dash throttle would then without the engine running move towards idle. The holes in the governor spring linkages is too adjust the governor sensitivity so as the engine does not hunt and surge at governor speeds. (the stronger the spring force the more forceful the governor) The governor springs are also color coded per engine codes but I've never seen them very critical of operation by color when I'm making Frankenstein engines. (taking several opposed twins engines and throttle plates and making one)
 
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