9n does not maintain rpm.

dryfly

New User
Help. My 9n slows down under load. Seems like governor not working. I just replaced the governor and distributor with new, and rebuilt the carb for this problem. Runs better now but it doesn't even seem to try to maintain rpms. It doesn't miss, stumble, or or backfire. It just slows down.
Regarding the governor, at what rpm is the governor supposed to kick in?
Starts and idles well, idle speed varies 400 to 450 rpm. any advice will be appreciated.
Dan B, WI
 
dryfly.........while both Ford and the I&T FO-4 say to set the down-pointing main jet to 1-turn, we recommend 2-turns and LEAVITT!!!

Now adjust the side-pointing idle-mix for FASTEST idle, NOT SMOOTHEST idle. Understand the difference???

Then adjust the behind the carb idle-speed for less than 500-rpms. Do the idle-mix...idle-speed at least 3-times. By following these instructions, you will gitter to idle close to 450-rpms. Usually the idle-mix will be in the 1/8-turn neighborhood.

I know yer 9N doesn't have a tach or "proof-meter", but just feel the side of yer hood with yer forehead/ear and you can semi-tell the engine speed increase and decrease. Precision rpms is NOT a necessity. Also, "crack" yer gascap 'cuz muddobbers are known to seal the tank vent at the front of the dome where you can't gitt-too. Tank vacuum will stop yer tractor after about 15-mins.

Governor starts at about 800-rpms, max governed speed is 2200-rpms. Some ungoverned 1/4-midget racecars could hit 3600-rpms, all that from weird Marvel-Schebler single carb........Dell, yer self-appointed sparkie-meister and carb tech
 
The tension on the spring of the governor cause the butterfly in the carb to open up, so it doesn't slow down (kinda like putting your finger under the slow idle adjusting screw). As a kid I use to put a branch under it and get to school faster, by running about 4000 RPM. Not a good practice on pistons.
The governor should fight against finger (and spring). to bring the speed back down. This is how you test your governor.
On my 2N, I had to put a wire thru first loop of governor spring to governor rod, to increase spring tension. Top speed can be increased or decreased by bending throttle shaft arm attached to block.
Play with the above action and you will get a better feel of your governor health to carb speed control health.
Charles Krammin SW MI
 
(quoted from post at 01:22:47 08/22/14) dryfly.........while both Ford and the I&T FO-4 say to set the down-pointing main jet to 1-turn, we recommend 2-turns and LEAVITT!!!

Now adjust the side-pointing idle-mix for FASTEST idle, NOT SMOOTHEST idle. Understand the difference???

Then adjust the behind the carb idle-speed for less than 500-rpms. Do the idle-mix...idle-speed at least 3-times. By following these instructions, you will gitter to idle close to 450-rpms. Usually the idle-mix will be in the 1/8-turn neighborhood.

I know yer 9N doesn't have a tach or "proof-meter", but just feel the side of yer hood with yer forehead/ear and you can semi-tell the engine speed increase and decrease. Precision rpms is NOT a necessity. Also, "crack" yer gascap 'cuz muddobbers are known to seal the tank vent at the front of the dome where you can't gitt-too. Tank vacuum will stop yer tractor after about 15-mins.

Governor starts at about 800-rpms, max governed speed is 2200-rpms. Some ungoverned 1/4-midget racecars could hit 3600-rpms, all that from weird Marvel-Schebler single carb........Dell, yer self-appointed sparkie-meister and carb tech
quote]

Thank you Dell and Charles for the prompt response.
I've got the idle rpm down to an unsteady 400-450(hooked up a test tach. When I replaced the distributor I ran a wire from the points out through the vent hole so I could connect a tach)

Main jet is open two turns.
Before I rebuilt carb and replaced dist and governor, I followed at tip I read in this forum regarding govs.
I connected a stiff wire to the throttle lever on the carb to the dash so I could manually open the throttle when I put a load on the engine. result was the engine stumbled and died.
Now, after replacing dist, gov, and rebuild carb, when engin rpms start to drop, I pull on the wire and can maintain rpms. Engine responds smoothly. Looks like prob is governor related.

Any advice? Thanks, Dan B










[/quote]
 
(quoted from post at 19:41:37 08/22/14)
(quoted from post at 01:22:47 08/22/14) dryfly.........while both Ford and the I&T FO-4 say to set the down-pointing main jet to 1-turn, we recommend 2-turns and LEAVITT!!!

Now adjust the side-pointing idle-mix for FASTEST idle, NOT SMOOTHEST idle. Understand the difference???

Then adjust the behind the carb idle-speed for less than 500-rpms. Do the idle-mix...idle-speed at least 3-times. By following these instructions, you will gitter to idle close to 450-rpms. Usually the idle-mix will be in the 1/8-turn neighborhood.

I know yer 9N doesn't have a tach or "proof-meter", but just feel the side of yer hood with yer forehead/ear and you can semi-tell the engine speed increase and decrease. Precision rpms is NOT a necessity. Also, "crack" yer gascap 'cuz muddobbers are known to seal the tank vent at the front of the dome where you can't gitt-too. Tank vacuum will stop yer tractor after about 15-mins.

Governor starts at about 800-rpms, max governed speed is 2200-rpms. Some ungoverned 1/4-midget racecars could hit 3600-rpms, all that from weird Marvel-Schebler single carb........Dell, yer self-appointed sparkie-meister and carb tech
quote]

Thank you Dell and Charles for the prompt response.
I've got the idle rpm down to an unsteady 400-450(hooked up a test tach. When I replaced the distributor I ran a wire from the points out through the vent hole so I could connect a tach)

Main jet is open two turns.
Before I rebuilt carb and replaced dist and governor, I followed at tip I read in this forum regarding govs.
I connected a stiff wire to the throttle lever on the carb to the dash so I could manually open the throttle when I put a load on the engine. result was the engine stumbled and died.
Now, after replacing dist, gov, and rebuild carb, when engin rpms start to drop, I pull on the wire and can maintain rpms. Engine responds smoothly. Looks like prob is governor related.

Any advice? Thanks, Dan B
Using the wire to the butterfly, to speed up under load, is what your rod from the governor to the carb butterfly should be doing.
With out running the motor, put the throttle lever to the max. The butterfly in the carb should be WIDE OPEN. If it isn't fiqure out why?
Could be like the carb to governor, is TOO LONG, or maybe the ends (with springs in them shot) or linkage from throttle to governor TOO LONG, sticking butterfly, etc.
If the governor while running, is right it should bring the butterfly back to set speed of throttle. If it doesn't then you have a governor issue. From what your stating I think your problem is in the spring and linkage between governor and not the governor.

Charles Krammin SW MI
/quote]
 
(quoted from post at 15:02:02 08/22/14)
(quoted from post at 19:41:37 08/22/14)
(quoted from post at 01:22:47 08/22/14) dryfly.........while both Ford and the I&T FO-4 say to set the down-pointing main jet to 1-turn, we recommend 2-turns and LEAVITT!!!

Now adjust the side-pointing idle-mix for FASTEST idle, NOT SMOOTHEST idle. Understand the difference???

Then adjust the behind the carb idle-speed for less than 500-rpms. Do the idle-mix...idle-speed at least 3-times. By following these instructions, you will gitter to idle close to 450-rpms. Usually the idle-mix will be in the 1/8-turn neighborhood.

I know yer 9N doesn't have a tach or "proof-meter", but just feel the side of yer hood with yer forehead/ear and you can semi-tell the engine speed increase and decrease. Precision rpms is NOT a necessity. Also, "crack" yer gascap 'cuz muddobbers are known to seal the tank vent at the front of the dome where you can't gitt-too. Tank vacuum will stop yer tractor after about 15-mins.

Governor starts at about 800-rpms, max governed speed is 2200-rpms. Some ungoverned 1/4-midget racecars could hit 3600-rpms, all that from weird Marvel-Schebler single carb........Dell, yer self-appointed sparkie-meister and carb tech
quote]

Thank you Dell and Charles for the prompt response.
I've got the idle rpm down to an unsteady 400-450(hooked up a test tach. When I replaced the distributor I ran a wire from the points out through the vent hole so I could connect a tach)

Main jet is open two turns.
Before I rebuilt carb and replaced dist and governor, I followed at tip I read in this forum regarding govs.
I connected a stiff wire to the throttle lever on the carb to the dash so I could manually open the throttle when I put a load on the engine. result was the engine stumbled and died.
Now, after replacing dist, gov, and rebuild carb, when engin rpms start to drop, I pull on the wire and can maintain rpms. Engine responds smoothly. Looks like prob is governor related.

Any advice? Thanks, Dan B
Using the wire to the butterfly, to speed up under load, is what your rod from the governor to the carb butterfly should be doing.
With out running the motor, put the throttle lever to the max. The butterfly in the carb should be WIDE OPEN. If it isn't fiqure out why?
Could be like the carb to governor, is TOO LONG, or maybe the ends (with springs in them shot) or linkage from throttle to governor TOO LONG, sticking butterfly, etc.
If the governor while running, is right it should bring the butterfly back to set speed of throttle. If it doesn't then you have a governor issue. From what your stating I think your problem is in the spring and linkage between governor and not the governor.

Charles Krammin SW MI

Charles, I'm new to this forum stuff. I'm not sure where I should be replying. Hope you get this.
Regarding the throttle butterfly, it IS wide open even when the throttle is only partly open. In fact, with the throttle lever only a quarter open, the engine will run at around 2000 rpm if I start it.

I think you're right about the linkages being a problem. I had to put big bends in the throttle lever to gov just to get the butterfly to close. This happened just before I started replacing parts. Going to order both new linkages.
Thanks so much for the quick responses!

Dan B [email protected]
/quote]
 

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