550 Industrial front hydro pump

Thanks for any advice you could give.

By the way, the tractor is back together and runs great (without the loader yet). I learned alot about the "overcenter" engagement of the PTO clutch from this exercise. It took the better part of one day to remove the loader and split the tractor, and the better part of the next day to clean and degrease the clutch and put it back together. Thats me, by myself. My shop has pneumatic tools, and an overhead I-beam, trolly and chainfall. Ask me someday about double locking set-screws.

Thanks for the suggestion. That would work well for a new installation, or if I can't find a replacement double chain coupling.

On the factory setup, the pump drive shaft also has a cushioned coupling on the engine front pulley. The drive shaft is splined to slide into this coupling, and "floats" there, so that the shaft can move axially front to rear. This tractor pulley coupling, being cushioned absorbs any torque shock and is also tolerant of minor misalignment between the motor and pump, allowing the double chain coupling on the pump end to be rigid. (A clever bit of engineering design.) There is no real need for two cushioned couplings with this set-up, and, in fact, if the shaft coming out of the pump were 14" long and splined, the double chain coupling would not be necessary at all, since to remove the pump, the splined end of the shaft simply slides out of the engine pulley coupling.

I prefer to keep my set-up as stock as possible, but your suggestion was certainly a good one and I'll keep it in mind, if I can't find the parts I need.

The whole thing with the front pump and PTO clutch started a couple weeks ago with the radiator core leaking (it was rotted out). At the time I didn�t realize the engine end of the pump shaft was splined and would slide out giving me access to remove the grill and radiator. I had not had this apart in the 13 years I�ve owned the tractor.

Since I wanted to remove the grill, I attempted to remove the sprocket coupling from the shaft. As long as I was removing the Oil tank and pump, I decided to remove the rest of the loader frame and split the tractor to fix the pesky PTO clutch. Since I did not fully understand the concept of an over-center locking clutch (no springs necessary), a remove, clean, replace, and re-adjust seemed the best way to go. It turns out I�m glad I did. Even though a new radiator core (now thicker with more tubes than stock) was $260. I saved as much as $1,200 doing the tear down, rebuild myself. I also replaced the belt and cooling hoses.

I grew up in the shop of my father�s Oliver dealership, in eastern Iowa, in the late fifties, early sixties. He and my uncle and grandfather sold tractors, implements, appliances, and cars from the late 1930�s to the late 1960�s. Though I am not a professional mechanic like my dad was, I have always enjoyed it, though a little less sometimes when it is 95 degrees in my shop and the locked setscrew wont budge.