51 farmall super c surging

[Boisdarc1]

Good mornining.
I have a 51 super c that is surging. It sat for 15 years. But i have managed to get started. She needs some love.

I have:
rebuilt zenith carb
New points and condenser wires coil and plugs
New battery and cables
Rebuilt governor with shaft and bushings
( fixed worn hole where springs attached)
Set governor linkage according to specs.
Spring on governor bottom adjustment changes nothing
Idle screw on carb changes nothing.
Changed all fluids ect

Motor is surging a bit and the range feels far from full rpm….

In addition gears are stuck. Will go into neutral, 3rd and 4th. Will not go into 1st , 2nd , or reverse. I would love to not take the differential cover off…..

Any advise from other readers would be greatly appreciated.

Thanks. James

 

[Boisdarc1]

Oh, i forgot. New governor assembly with throw out bearings….

 

[grandpa Love]

Surging is usually caused because the linkage from the carb to the governor needs adjustment. Even if it's set to book specs. We have adjusted them back and forth until we find the sweet spot.

 

[Brownie450]

Sitting for 15 years the shifting gates could be rusted
to the point that they won't move. Does the tractor
move in 3 & 4? If so, the differential probably is still
free & the trouble is in the shifter rails.
Jim

 

[Boisdarc1]

Yes brownie450. I could move in 3/4th gear. Just wont shift to others. O way to free from shifter opening if i remove pin? I remember pulling off top and it was a b_$@%# to get gears aligned…

 

[Brownie450]

Man should try everything to loosen things up instead of pulling the platform.
Sounds like the shifting lever won't go side to side. Since 3 & 4 work, it's probably
stuck with 1 or 2 blocking the lever going over to the 1 & 2 gate.
Possibly just hanging up blocking the shifting gate.
Jim

 

[560Dennis]

You getting enough fuel at all rpm ?
Is the bumper spring making contact with the lever ?

 

[Brownie450]

We've never had our SC shifting lever pin out to pull the lever &
see how the gates line up. Had our bigger tractor shifter pins
out, but never the SC. If it has a pin, I'd definitely pull the shifter
& have a look. Guess I never looked for a pin on the SC.
Jim

 

[Boisdarc1]

Thanks grandpa love -i messed with the linkage and pushout out about 3/16 forward from specs. Runs much better.

Applied impact hammer (without bit) to try and shake vibrate into movement but still stuck in n/3/4. Pin ins in there frozen, but ill try and get out after the weekend. Boy, i hate taking the tope off. Thanks for everybody’s input…. Even tried melting pb blaster tube to a 90 degree angle and emptying a can on the rails through the fill hole.. nada……

 

[Boisdarc1]

The stuck in 3/4 turnout out to be the ball in the shift stick rusted and frozen. Banged out with hammer and all is fine . Still surging a bit. Might try a distibutor rebuild?

 

[MM-TX]

The stuck in 3/4 turnout out to be the ball in the shift stick rusted and frozen. Banged out with hammer and all is fine . Still surging a bit. Might try a distibutor rebuild?

Make sure the bumper spring in the governor is not broken or bent and is adjusted right.

 

[Boisdarc1]

I did adjust bumper spring(new) in and out. No engine improvements ( no change ) in or out…..

 

[Boisdarc1]

Ok. Follow up…. Running rough and surging. Tried to rebuild distributor but had trouble with a screw and broke the housing with an easyout. Got new distributor from this site and installed. Runs much smoother but still no throttle depth and rpm still seem low. So i Screwed in buffer spring screw almost all the way. Pushed the carb link to gov adjustment towards front 3/16 inch. Here is where it gets weird. Ran as best as i havecever heard…. Great throttle great rpm ect. Took a spin around the neighborhood for about 8 min then throttle down around a corner and it almost stalled and started sputtering. I thought fuel. No fuel was fine. Strainer clean and gushed nicely when opened up. The buffer spring after removing was hard to get out and seem to bind with whatever it pushes against in the gov housing. I removed and it was bent to hell. Does anyone have an idea why that was getting bent( was brand new when i rebuilt the gov a month ago……
Thanks again

James

 

[grandpa Love]

Man.....we have seen weird stuff. Had a super a , couldn't get the throttle to rev up and down correctly. Fooled with it for hours. Finally noticed that the steering post had been bent forward a good bit, this affected the length of the throttle rod . We have also found broken,worn out ,non springy springs on the end of the throttle rod where it hooked to the governor. You said you moved the linkage from the carb 3/16??? We have moved that clevis back and forth through the whole threaded portion of the rod hunting the sweet spot. Unfortunately we have also had a governor,that for whatever reason we couldn't get to work correctly. We compared it to 5 other governors in our parts bin, everything looked exactly the same. Everything moved the same, appeared to be the same wear on everything. Finally swapped the whole thing, governor and case ,and it solved the issue. No idea why,or what was wrong. Your issue would be easier to solve if we could get our hands on it

 

[Boisdarc1]

Grandpa love
Why would a new buffer spring bend? Screwed in too far? Ill keep messing with the linkage but between the linkage and the buffer i feel like have been all over the place…

 

[Janicholson]

New springs can be made that have no temper in the metal after fabrication. Jim

 

[Jim Becker]

Grandpa love
Why would a new buffer spring bend? Screwed in too far?

That was my first thought. That spring should not need to be in more than enough to apply light pressure. Just guessing, when the rockshaft lever rotated away from it, the end of it popped out of position. Then the rockshaft lever rotated towards it and bent it.

I say go back to the basics. Does the carb idle screw still have no effect? Clean the carburetor until it does. There is probably one or more small passages that need some carb cleaner and a small wire run through it. Then blow it out with air. After that, readjust the linkage from the governor to the carb and make sure it moves freely with no binding. After it is running right, adjust the bumper spring in the absolute minimum required to control surging. Don't try to fix anything else with the bumper spring. Turning it in too far will increase low speed idle (override the idle speed screw on the carb). If the engine won't turn up to full speed, the problem may be a weak governor spring or the speed change lever not applying enough pull to the governor spring.

 

[Boisdarc1]

Thanks jim,

Where is the speed change lever?

 

[Janicholson]

Thanks jim,

Where is the speed change lever?

The hand lever at the driver's station is also called the "throttle" and "speed change lever".
linkage
The engine end of the throttle linkage has two springs on it. The throttle hand lever needs to be able to move the governor control lever through its full range. this can be checked not running. If it does not, the springs can be adjusted/replaced to make that happen. Jim

 

[wore out]

Good mornining.
I have a 51 super c that is surging. It sat for 15 years. But i have managed to get started. She needs some love.

I have:
rebuilt zenith carb
New points and condenser wires coil and plugs
New battery and cables
Rebuilt governor with shaft and bushings
( fixed worn hole where springs attached)
Set governor linkage according to specs.
Spring on governor bottom adjustment changes nothing
Idle screw on carb changes nothing.
Changed all fluids ect

Motor is surging a bit and the range feels far from full rpm….

In addition gears are stuck. Will go into neutral, 3rd and 4th. Will not go into 1st , 2nd , or reverse. I would love to not take the differential cover off…..

Any advise from other readers would be greatly appreciated.

Thanks. James

If the carburetor is CLEAN, the linkage between the governor and carburetor is adjusted according to the book. the linkage isn't sticky or "sloppy"and the governor is in good shape (no sticking parts, no "flats' worn on the weight fingers and fork), etc. the engine should not "surge".

The "bumper spring" needs to be used sparingly or not at all, it's just a "crutch" to help a little, of needed, and NOT intended for the screw to be in a long ways.

That simply interferes with the proper action of the governor and wrecks the spring, as you've found out.

Across a wide swath of engines such a thing (the governor bumper spring) is VERY rare, and they operate just fine with similar carburetors without it.