With the tractor running... Move the throttle forward. Look to see if the linkage on the governor is moving.
If it is..., sounds like it may be the thrust bearing on the governor. Easy to access, just remove the front cover on it. Look behind the fingers on the cross shaft. There are actually 3 pieces to it. They will deteriorate over the years. Usuallly the cage holding the tiny ball bearings breaks.
I've included an exploded view of the gov. assembly. The bearing is #25.
If memory serves me correctly without looking at the service manual.. I'm thinking you can remove the pin from the bell crank (#14) on the carb side. Then remove the spring that holds the fingers back agaist the thrust bearing. This will allow the fingers to rock forward, to R&R the bearing. But definitely look at your service manual before doing this...!! Sometimes my memory plays tricks with me...
My first experience with this was with my BN. It ran fine, but would only run at about 1/3 throttle. Replaced the bearing, and it was as good as new. I believe I have replaced all of them on what I have, at one time or another.
Being I have 6 tractors with the C-113 or C-123 engines, I keep one on hand. And I do believe the firs one I bought was 75 cents, LOL... I'm sure they are more than that now...
