2nd gear seized in transmission

[heartofdarkness]

I just split the cases on a '99 Warrior to diagnose a stuck- in -gear problem. The 2nd gear "wheel" (that is, the physical gear) was seized to the "drive axle" shaft, and had to be pressed off. Both the inside of the gear and the shaft were seriosly galled. Nothing else in the bottom end showed any problems; all the bearings were in good shape, the gears show almost no wear. There were no metal shavings or dirt particles in the crankcase or filter, and there was enough oil.

Does anyone know what might have caused this?

 

[Guest]

wow sounds like a rare occurance warrior transmissions are like bullet proof u didnt bend or break a shift fork or anything? so your saying its seems in condition to where since u pressed it free you could prolly put it all back together and it would prolly work again? did it get really hot when this happend?

 

[heartofdarkness]

This was a used Warrior that was just bought, so there's no knowing what the last owner did to it. He claimed that it was sitting at idle when the transmission locked. No gear teeth were broken, so that might be true.

The shift forks look fine. There is an oil channel that runs through the shaft, and crosswise oiling holes that lubricate the two free-spinning gears on that shaft. The other gear doesn't seem to have any problems, only that 2nd gear gear. My guess is that the oil channel got clogged, but there wasn't any evidence of that.

Both the gear and the shaft will need to be replaced; there was significant galling, and metal was both removed from and deposited onto both. Both pieces have some discoloration from overheating. Because the gear is supposed to spin freely on the shaft, both surfaces need to be super polished and hardened.

 

[Guest]

yea i think something wasnt getting oil to it like it should have...sitting at idle builds up heat alot to...air cooled engine...and it ended up getting hot warped a gear and them it just froze up...prolly that oil channel u mentioned...previous owner prolly did something dumb...it would help too install an oil cooler also so hopefully this would never happen again...theres threads on here somewhere about it, if i were you id prolly try to find some used tranny set on ebay...