I have a model 1430 that I just inherited from my grandfather and I got it runnig yesterday and it runs great. Motor real easy to work on. Everything seemed to be fine until I put it under a load by pulling an ATV plow and it started jumping like it was jumping in and out of drive. I have not taken the transmission apart yet or the final drive but would like to attempt that tonight. Anything to look for or maybe something common with them that is a quick fix where this is a known issue? This happened in 1st, 2nd, and 3rd gear.
Also, the serial number shows it is a 1671. Can you tell me what year it was anufactured in?
Here is other info on it that I found:
Spirit of America