I have a Series III D-17 that the governor will run away on when it is at is sitting at idle...when you move the throttle lever back to the idle position the RPM's will go back to idle.  From what I can remember this problem started back in the early 1990's when my Dad got a bigger manure spreader, which was probably too big of load for the tractor, hit a bump in the field with a full load and broke the drawbar and this governor issue accorded at the same time.  He had it to our local dealer which still had A-C mechanics at the time, they had it apart and couldn't find anything wrong with it and he took it to a local A-C after hours mechanic and he couldn't find anything wrong with it either.  Dad passed away a few years ago and left the tractor to me and I thinking of tearing into but have no idea what to look for...any suggestions...thanks in advance.

I was watching the tractor last night while it was running...I was initially thinking throttle linkage issue too but the control rods do not move as the engine RPM increase...the friction discs would let the control rods move correct?  So I was leaning to a problem internal in the govenor like damaged weights but when others had it apart I would think they would have spotted that?  The tractor was parked after Dad bought a D-19 and this D-17 had this governor issue even after two different people had it apart to try and fix it. 

My throttle linkage has been adjusted all the way out already and the friction discs are tight enough that it is almost difficult to operate the throttle back and forth in my opinion...I talked to one of the guys that is still alive that maybe worked on the tractor twenty years ago and he was gonna check his old repair orders to see if the governor was opened up but hasn't got back to me yet...either way it appears the governor will have to taken apart and inspected.

I have checked the spring underneath on the throttle and it is not off centered?  Seems to be springing back and forth fine when you move the throttle linkage...I have the governor apart on this tractor now and can see no problems with it like the previous inspectors before me...weights are in tack and not loose...the bearing up front seems to operate as it should and the governor spring seems to be doing it's job also.  We did also have the carburetor apart and found some possible issues...by the looks of things inside there I don't think it has been apart since the old days when it sat outside on the farm...with these corrections and linkage adjustments I'm hoping it fixes this problem as I can find nothing wrong with the governor.  I have a A-C service manual I borrowed from a dealer and it says in there while setting the carburetor link rod you're supposed to set the throttle lever in the midway position on the quadrant and have the carburetor link rod wide open?  Why would it be that way?  The WD 45 book we have says to set the lever wide open with the carburetor link wide open?  Any thoughts?  

I have this D-17 put back together and everything seems to run fine now...I might need to do some fine tuning on the carburetor but that is it.  I had looked at the fork and it was not loose at all and I checked it several times while checking the throttle lever operation.  I guess ultimately the only adjustment I made was putting a small block of wood behind my governor rod and bending the rod back about an 1/8" inch to get my 1/16th preload on the carb linkage...somebody in the past had bent both the rod and linkage so short that I basically had no throttle lever operation at all...it was either idle or wide open...I don't know if this bad adjustment had anything to do with the tractor running away at idle, but after my adjustment I don't have this problem anymore.  I was never able to find anything wrong with the governor like the previous people that had it apart before me.  I have taken the tractor for a test drive a couple times and have a throttle lever that adjusts RPM's and holds the speed now and have let the tractor sit and idle a couple times for twenty minutes without the governor running away on it.  Hopefully this problem is solved.  Thank you for all the help along the way.