The front pulley on my OC-3 keeps on shearing the retaining pin that goes through the crank and the pulley. I replaced the pin that was there with a 1/4" x 2 1/2 bolt, but it shears off the top of the head after a few minutes. Is there a specific pin that will hold the pulley in place and is there suppose to be a key in the shaft. Before I tear it all apart is there any thing that I should be aware of.
Greg
Is this the pin that the crank hooks into for starting? I recall having a problem like that years ago too. I think it was with my General. Have you tried a roll pin?
What accessories are running off you front pulley ââ,¬â€œ I am having a similar problem with mine not being able to drive the hydo pump ââ,¬â€œ I am looking for picture of a setup that runs right off the end of the crank shaft ââ,¬â€œ I have started to design something using lovejoy shaft to min vibrations , but could use visuals
Thanks for the replies.
The pin goes through the back of the pulley and through the crankshaft. Right now the hole is pretty elongated in the pulley. I don't know if the crank hole is true anymore either. A role pin might work but I am wondering if the crankshaft is keyed and the key is sheared off.
The pulley drives the hydraulic pump in front of the radiator.
Although the engine will run with out the pin, the water pump, alternator, and hydraulics won't go.
Thanks for the interest.
Greg
My IX book showes a keyway 90 degrees from the pin hole so your thaughts about the keyway are correct. As long as the shaft and pulley are not chewed up to bad a new key should solve the problem.
Robert is correct. I tried to post a little while ago and it would not let me do that. The parts book list a key. I am guessing that neither one of you took the pulley off and looked for a keyway or a sheared key. The pin is a loose fit pin and is held in place with a cotter pin. Questions?
Thanks again for the suggestions.
I will pull the pump and radiator out and take a look.
Any suggestions on where I might find a new pulley for this unit.
Greg
the best place for parts is Zimmernmans Oliver-Cletrac in Ephrata Penna.
He would probably have any part you may need.
I feel the key is to have a snug fit on the pulley/crankshaft and a tight fit on the pin/keyway and you should be in good shape. if there is any slop that the pulley can turn back and forth, there would be more torque there to shear it off. both the hole in the pulley and crank should be round and the key has to fit snug.
Zimmerman's Oliver Cletrac
1450 Diamnd Station Rd. 17522
Phone-717 738 2573
Well I decided to get into this weekend and pulled the pump and the radiator off the tractor. Between the pump and the pulley is a coupler that looks like a piece of pipe with a solid but floating core with a single verticle key on each side that sits in a channel at the end of the pulley and the pump. It also has a grease fitting too. The pulley is actually oversize from the crank and just flops around on the end. There is a keyway on the shaft but not the pulley. The hole in the shaft and the pulley were both elongated. I realize the it will require a major overhaul to replace/repair the crank so to keep things running I reamed the hole in the crank to accept a 5/16" bolt instead of a 1/4". That will hopefully keep it running for awhile.
It has run a long time the way it was set up. I can't imagine that this was actually a stock set up. Maybe it will be time to rethink the hydraulic pump gearing when the overhaul becomes imminent.
Thanks for all the suggestions. I will contact Zimmerman about the parts.
Greg