Last summer I posted about the 1948 Z on the farm.
I only get a chance to play with tractors a couple weeks a year on vacation so it takes a while to get back to it!
It will idle OK, but starts to run rough and cut out some with any sort of load, even just driving up a light grade. Can"t trust it to stay running to pull a empty wagon even.
The tractor had been sitting a few years and I thought maybe old gas. The gas has been changed out and I put new plugs in but there was no change.
For good measure I cleaned out the air cleaner and gave it a oil/filter change for probably the first time in >15yrs. Fortunately, I found a couple of the NLA cartridge oil filters in the shed. I didn"t expect that to have any bearing on this problem but it made "me" feel like I did something, haha.
Any rate, I wondered if there was a vacuum leak someplace as I could hear some hissing when I had the throttle opened up over idle and stood nearby the intake. I vented some propane torch gas around the intake to head gaskets but that didn"t have any effect. Trying to track the hissing down I discovered that it was not there at idle but when the throttle was higher, the governor was having a bit of a problem: When the engine would run rough and cut out, the governor would try to keep it up by pulling the carb throttle arm (as expected). Then I could hear the hissing get worse.
So, I manually wiggled the carb throttle shaft and discovered its really floppy in the carb. Could the air leakage here be causing this problem? I remember years ago we had a old mower that would race speed up/down because the throttle shafts flopped in the casting.
I see from some searching there is a bushing available for this. Was/is there one in there originally (I haven"t tried to clean or take the carb apart yet)? If not, I presume I need to have the casting bored out by a shop to press this in? What about any seals?
Thanks in advance.