We bought this little tractor about 10 years ago as a reman. Apparently the tractor is over 40 years old. Unfortunately the decal (SL1643) doesn't match to stamp on the block (SD 1643).
Anyway I am guessing the stamp is more accurate. The other day when I was trying to start it after warming the glow plugs, it would putt once, then whirl or make a spinning sound. After playing with it for about five minutes it started and ran normal. I tried starting it later and it tried to do the same thing. I check to voltage - 12.7v. Any idea what might be wrong?