Governor issue on Farmall 100

[52farmall]

I recently pulled the Zenith carburetor off of my 1956 Farmall 100. I planned on doing a rebuild kit but haven't gotten to it yet. I needed to move the tractor and re-installed the carb but when I went to reinstall the rod that goes to the governor rockshaft arm, the clevis didn't line up with the governor arm. I followed the procedure listed in the manual for setup, wide open throttle, holding the governor and rod all the way toward the carb, etc. They just won't line up like before. I adjusted the clevis on the rod going to the carburetor and I just don't have enough thread to shorten it, it's way too long. When I did start up the tractor when I reattached it, it ran at wide open unless I push the rod forward toward the governor and hold it. I can fiddle with the adjustments enough to get it to idle but there isn't any throttle response until I reach about 3/4 throttle then it goes from idling to almost wide open.

I now have the carb kit and plan on rebuilding it in the coming days. I also took the governor housing off and ordered the main spring for it. The one that is currently installed doesn't feel stretched out or worn and actually feels pretty tight. The weights move freely and the thrust bearing seems fine. I'm at a loss at the moment as I don't know if it's a carb issue, or a governor issue. I've searched the forum, google, and YouTube, but each governor scenario seems different from mine and there just isn't a lot out there about them that I can find. Any guidance or advice is appreciated!

 

[Janicholson]

Diagram
Is the fork (part 21 in the image) that connects to the rock shaft Part 20. out of place on the governor plunger? Jim

 

[Jim Becker]

Any chance you connected the governor to the choke arm and the choke control to the throttle arm? I'm not sure that would make the rod seem too long. But I can't think of anything else that would make a huge difference longer or shorter.

 

[52farmall]

Diagram
Is the fork (part 21 in the image) that connects to the rock shaft Part 20. out of place on the governor plunger? Jim

I haven't checked that but I will. Maybe I can find a pic or video that will show the correct orientation.

 

[52farmall]

Any chance you connected the governor to the choke arm and the choke control to the throttle arm? I'm not sure that would make the rod seem too long. But I can't think of anything else that would make a huge difference longer or shorter.

I don't think so. I compared it to my dad's Super A and it seems to be linked up the same as his.

 

[52farmall]

These are some pics of what I have right now. This is the governor housing. I have removed the spring and awaiting the replacement; which should be here tomorrow.

The other pics of the rod connecting the governor and the carburetor. This one is the carb at wide open (held by hand since the governor housing is off)

This is at idle, again held by hand.

This is the governor without the housing. I'm very confident here at what I'm looking at so if something wrong sticks out that I don't see, please let me know. The weights move freely.

 

[JoeVT]

This is probably not your problem but I’ll share my govenor problems on my sa. Previous owner rigged it so it was wot. I started looking at it and adjusted the rod to the manual. At that point it only idled. Took the govenor off and found a mess. The arm that holds the spring had a deep groove in it. I jb welded that. The needle bearings on the rockshaft arm had failed, creating grooves in it. I ended up rebuilding all of that. A new rockshaft is very expensive. Not sure if this is your problem, just sharing my experience.

 

[crsutton81]

I recently pulled the Zenith carburetor off of my 1956 Farmall 100. I planned on doing a rebuild kit but haven't gotten to it yet. I needed to move the tractor and re-installed the carb but when I went to reinstall the rod that goes to the governor rockshaft arm, the clevis didn't line up with the governor arm. I followed the procedure listed in the manual for setup, wide open throttle, holding the governor and rod all the way toward the carb, etc. They just won't line up like before. I adjusted the clevis on the rod going to the carburetor and I just don't have enough thread to shorten it, it's way too long. When I did start up the tractor when I reattached it, it ran at wide open unless I push the rod forward toward the governor and hold it. I can fiddle with the adjustments enough to get it to idle but there isn't any throttle response until I reach about 3/4 throttle then it goes from idling to almost wide open.

I now have the carb kit and plan on rebuilding it in the coming days. I also took the governor housing off and ordered the main spring for it. The one that is currently installed doesn't feel stretched out or worn and actually feels pretty tight. The weights move freely and the thrust bearing seems fine. I'm at a loss at the moment as I don't know if it's a carb issue, or a governor issue. I've searched the forum, google, and YouTube, but each governor scenario seems different from mine and there just isn't a lot out there about them that I can find. Any guidance or advice is appreciated!

I'm definitely not an expert on this as I'm learning myself while working on a Super A at the moment. On this tractor that I have in the shop, the bumper spring is broken into 3 pieces and makes the throttle really unpredictable and not idle as it should.....plus want to run at higher speeds than the throttle is set at. If you haven't done so, I would remove the plug that it fits inside of and take a seal pick and withdraw it from the plug housing and inspect. More than likely you will find it is also broken but looks good to the naked eye until trying to dig it out.

 

[crsutton81]

View attachment 101565View attachment 101566View attachment 101567
I'm definitely not an expert on this as I'm learning myself while working on a Super A at the moment. On this tractor that I have in the shop, the bumper spring is broken into 3 pieces and makes the throttle really unpredictable and not idle as it should.....plus want to run at higher speeds than the throttle is set at. If you haven't done so, I would remove the plug that it fits inside of and take a seal pick and withdraw it from the plug housing and inspect. More than likely you will find it is also broken but looks good to the naked eye until trying to dig it out.

Here's the parts breakdown for the governor. A thought that also crossed my mind is where the governor rockshaft arm ( # 14)that the carb linkage attaches to, could it be loose on the governor rockshaft ( # 16) and was dislodged a bit while trying to disconnect the carb linkage ? It is a tight and aggravating space to connect things up on the carb. The parts book does list # 15 as being a Woodruff key in that connection of arm to shaft. Hope this helps.

 

[Fritz Maurer]

Sounds like you had the governor apart first and omitted the thrust bearing.
Removing the carb and replacing it without disturbing the governor would not have the linkage alignment problem you are describing.

 

[52farmall]

View attachment 101565View attachment 101566View attachment 101567
I'm definitely not an expert on this as I'm learning myself while working on a Super A at the moment. On this tractor that I have in the shop, the bumper spring is broken into 3 pieces and makes the throttle really unpredictable and not idle as it should.....plus want to run at higher speeds than the throttle is set at. If you haven't done so, I would remove the plug that it fits inside of and take a seal pick and withdraw it from the plug housing and inspect. More than likely you will find it is also broken but looks good to the naked eye until trying to dig it out.

Thanks for all that information. I'm definitely going to look into the bumper spring while I have the governor housing off. What you described above about the throttle being unpredictable and running at higher speeds than the throttle was set are issues I had on this tractor before I started taking things apart.

I also thought about the rockshaft arm being out of position on the shaft but there is a woodruff key and it appeared to be in place where it should be. I'll double check though.

 

[Jim Becker]

In your pictures from last evening, the lever arm on the throttle shaft of the carburetor looks like it is positioned too far forward, as if the position of it relative to the throttle plate is wrong. Maybe it is just the way I am seeing the picture. Furthermore, I can't think of a way it could be wrong, particularly if you haven't done any disassembly/reassembly of the carburetor. But if the lever has somehow gotten out of position as it appears, you would get the effect of the rod being too long.

 

[52farmall]

In your pictures from last evening, the lever arm on the throttle shaft of the carburetor looks like it is positioned too far forward, as if the position of it relative to the throttle plate is wrong. Maybe it is just the way I am seeing the picture. Furthermore, I can't think of a way it could be wrong, particularly if you haven't done any disassembly/reassembly of the carburetor. But if the lever has somehow gotten out of position as it appears, you would get the effect of the rod being too long.

My dad mentioned the same thing and we wonder if somehow the link where the governor rod connects to the carb has rotated "out of sync" and causing the issue. I took the carb off the tractor first before I even touched the governor and it is a tight space to be disconnecting the rod from the carburetor; maybe I bent, twisted, or over-rotated something. I've got the complete rebuild kit for the carb and hope to rebuild it tomorrow. I'm hoping it's something simple like that. If not I'll go back to square one and see.

 

[Jim Becker]

Before you start to disassemble it, look down the carb to the throttle plate and see that it is in position and moves properly with the lever.

 

[52farmall]

Over the weekend I got the carb rebuilt and I do believe the shaft on the carb had rotated or moved; we now have space to connect the rod to the governor rockshaft arm. The length is still a little tighter than before, but it will work. I replaced the governor spring (5) while I had the governor off. The tractor will fire and run/idle; but there is limited throttle. Wide open on the control is only about 1/2 wide open. We took the distributor back off and I noticed the thrust pin (19) was stuck and only protruding about 1/4 of an inch from the shaft. I PB blasted it and with a little bit of heat it is now freed and moving smoothly. With the tractor running again, now when you give it throttle, it surges or hunts. According to the manual I have it says to adjust the surge bumper spring. I took that off for adjustment and the spring was seized inside the adjusting screw. When trying to free it, it broke and was rusted in two. I'm picking up a new surge spring (21) and and a new thrust spring (18) tomorrow. My question is, how far does the thrust spring and pin (19) extend off the governor shaft? We haven't removed the pin in fear of breaking the spring and I'm not trying until I have the spare spring in hand tomorrow. Also, once the new surge spring is installed, should that alleviate the surging/hunting the engine is doing? Where does the speed adjusting screw (8) come into play in setup? Attached is the diagram with numbers for reference.

 

[wore out]

"I do believe the shaft on the carb had rotated or moved"

It would be interesting if you would elaborate upon exactly what happened there, was the pin holding the throttle arm to the butterfly shaft missing or broken?

As to the spring and pin 18 and 19 I DOUBT if getting things up to par there will affect your surging issue. The governor is driven by helical gears that tend to force it to stay rearward while the engine is running. Likely, the little spring helps keep the governor shaft rearward and fully engaged with the distributor or mag drive as the engine is costing to a stop.

As to the surge bumper spring, IH was, for the most part, unique in using those.

Surging is often a carb issue, in that there's not a proper transfer back and forth from the idle circuit to the power circuit and vise-versa.

I've had a number of similar IH engines that run just fine with a missing or broke surge bumper spring.

 

[crsutton81]

I recently pulled the Zenith carburetor off of my 1956 Farmall 100. I planned on doing a rebuild kit but haven't gotten to it yet. I needed to move the tractor and re-installed the carb but when I went to reinstall the rod that goes to the governor rockshaft arm, the clevis didn't line up with the governor arm. I followed the procedure listed in the manual for setup, wide open throttle, holding the governor and rod all the way toward the carb, etc. They just won't line up like before. I adjusted the clevis on the rod going to the carburetor and I just don't have enough thread to shorten it, it's way too long. When I did start up the tractor when I reattached it, it ran at wide open unless I push the rod forward toward the governor and hold it. I can fiddle with the adjustments enough to get it to idle but there isn't any throttle response until I reach about 3/4 throttle then it goes from idling to almost wide open.

I now have the carb kit and plan on rebuilding it in the coming days. I also took the governor housing off and ordered the main spring for it. The one that is currently installed doesn't feel stretched out or worn and actually feels pretty tight. The weights move freely and the thrust bearing seems fine. I'm at a loss at the moment as I don't know if it's a carb issue, or a governor issue. I've searched the forum, google, and YouTube, but each governor scenario seems different from mine and there just isn't a lot out there about them that I can find. Any guidance or advice is appreciated!

Ok...after rebuilding the governor on this Super A, the bumper spring ( number 21 in your picture) IS critical to fine tuning the surging. First thing though, is your thrust bearing on the governor shaft still in good condition ? It is a 3 piece assembly....a washer ring, then the ball bearing retainer, then the other washer ring. All 3 parts make up the thrust bearing. Are all of the bearing balls present and not chewed up ? Assuming all is well there, spring number 18 in your picture has no monumental effect other than keeping VERY slight tension to keep the shaft pushing inwards towards the distributor for positive contact. The little pin presses against the center of the gov housing cap. So long as there no major slop there, you'll be ok. It has nothing to do with governor action really. Part number 20 in my pictures above fits onto the governor rockshaft ( number 16 ) that controls the carb linkage rod. It is roll pinned by part number 21 to tie part number 20 to part number 16. It could potentially be deformed if much grief was applied while removing the carb in the beginning. The main things that will effect the governor action are setting the gov to carb control rod to specs ( see above directions in the earlier picture post that I made), and the bumper spring. The more that the bumper spring is screwed in, the more low idle effects there will be, along with less surging. If the above mentioned governor to carb linkage is not setup appropriately from the git go, your fighting a loosing battle. Once you get to where the engine speed can be gagged from full idle to wide open throttle and it surges a full time and a half, you have it set correctly. Hope this helps.

 

[52farmall]

"I do believe the shaft on the carb had rotated or moved"

It would be interesting if you would elaborate upon exactly what happened there, was the pin holding the throttle arm to the butterfly shaft missing or broken?

As to the spring and pin 18 and 19 I DOUBT if getting things up to par there will affect your surging issue. The governor is driven by helical gears that tend to force it to stay rearward while the engine is running. Likely, the little spring helps keep the governor shaft rearward and fully engaged with the distributor or mag drive as the engine is costing to a stop.

As to the surge bumper spring, IH was, for the most part, unique in using those.

Surging is often a carb issue, in that there's not a proper transfer back and forth from the idle circuit to the power circuit and vise-versa.

I've had a number of similar IH engines that run just fine with a missing or broke surge bumper spring.

The link where the connecting rod connects to the carb was positioned too far forward and not allowing enough room to connect the butterfly shaft to the rockshaft arm of the governor. The kit I used to rebuild the carb came with a new shaft so I didn’t examine the old shaft very close. The only thing I can figure is I bent or twisted it while removing the carburetor.

 

[52farmall]

Ok...after rebuilding the governor on this Super A, the bumper spring ( number 21 in your picture) IS critical to fine tuning the surging. First thing though, is your thrust bearing on the governor shaft still in good condition ? It is a 3 piece assembly....a washer ring, then the ball bearing retainer, then the other washer ring. All 3 parts make up the thrust bearing. Are all of the bearing balls present and not chewed up ? Assuming all is well there, spring number 18 in your picture has no monumental effect other than keeping VERY slight tension to keep the shaft pushing inwards towards the distributor for positive contact. The little pin presses against the center of the gov housing cap. So long as there no major slop there, you'll be ok. It has nothing to do with governor action really. Part number 20 in my pictures above fits onto the governor rockshaft ( number 16 ) that controls the carb linkage rod. It is roll pinned by part number 21 to tie part number 20 to part number 16. It could potentially be deformed if much grief was applied while removing the carb in the beginning. The main things that will effect the governor action are setting the gov to carb control rod to specs ( see above directions in the earlier picture post that I made), and the bumper spring. The more that the bumper spring is screwed in, the more low idle effects there will be, along with less surging. If the above mentioned governor to carb linkage is not setup appropriately from the git go, your fighting a loosing battle. Once you get to where the engine speed can be gagged from full idle to wide open throttle and it surges a full time and a half, you have it set correctly. Hope this helps.

The thrust bearing is in good shape as you described. I’m going tomorrow and get the springs and I’m hoping the bumper spring helps with my issue. Thanks for all the info.

 

[Jim Becker]

The surge spring is there to deal with surging. Although this sounds odd to say it, it is the last thing to adjust to stop the surging. The engine first needs to be properly tuned-up, including checking the timing. The carburetor mixture needs to be set right. Then the fast idle speed should be set by turning screw 8 in for slower or out for faster. Once all these things are good, adjust the surge spring to dampen out the surging. If starting from scratch, start with it turned out. Turn it in no more than needed to control the surging.