1755 PTO Valve

Genz · Mar 11, 2020

Maybe someone with more knowledge than me can shed some light on this subject. Were having issues with the PTO staying engaged, so we proceeded to take the valve off to inspect. Please see the attached mocked up picture of what we've encountered...I suspect the 1/4 ball that lives in the machined bore acts like a detent. But how does it work? On the valve we took off the working tractor, there is a piston with a 1/4 ball underneath it, no spring in this assembly... On the valve we took off the parts tractor, there is a spring with a 1/4 ball underneath it, no piston! I assume the spring keeps pressure on the ball, when the valve moves, the ball falls into a groove keeping the PTO engaged...We don't have a spring in the valve assembly we took off on the working tractor....Is this our problem, why the PTO won't stay engaged?

J. Schwiebert · Mar 11, 2020

Does the tractor have a cab? Did you check circuit pressure? Do you have serial number for the 2 tractors? There were changes made in those valves. Send me an e-mail and include phone number. J.

Genz · Mar 11, 2020

Parts tractor S/N.. 234 078 676
Working tractor S/N 242 136 676

No we haven't checked pressures yet. Just finishing up putting this rig back together after the trans input shaft went south. We did find while apart: the oil pick up tube on the internal trans pump fell off, sitting on the bottom of oil reservoir. I assume the PTO takes this pump pressure to stay engaged as well, so that might of been our problem? . Perhaps, reinstalling the pick up tube will solve our problem, but dont know. We thought while it was in the shop we'd pull off the PTO valve to change o-rings and found this issue with no spring

email: [email protected]
Ph : 319- four-four-4 -zero-2-six-1

Genz · Mar 11, 2020

Oops, no cab either

2-strokeDD · Mar 12, 2020

The valve from your working tractor is a later model valve. Notice it also has a set screw on the bottom.Your working valve does not need a spring because oil pressure pushes on the plug and puts the detent
ball into the valve to hold it on. this way if you shut the tractor off with the PTO on it will release and when you restart the tractor the PTO will be off.The transmission pump supplies oil to lubricate the
trans. and PTO it has nothing to do with the valve. The first thing to do is to tee in a gauge on the pressure line going into the valve. Check the pressure with the PTO on and off and also check to see if the
pressure stays the same when you apply the tractor brakes. There is a pressure reducing valve on the valve stack below the hydraulic pump that controls the pressure for the PTO and brakes.

Genz · Mar 12, 2020

2 -Stroke Thank you for your wisdom. What kinda pressures am I looking for? Which line is the supply line?

2-strokeDD · Mar 13, 2020

You should have between 200 to 240 psi. The pressure line is the long one that goes under the platform of the tractor. The return line is only a foot or so long and goes straight up to the reservoir.

Genz · Mar 13, 2020

Thanks again. We'll test it when we get the motor back in and running. Any places better than other to buy a gauge that will read this high?

1755 PTO Valve

Genz

Member

J. Schwiebert

Well-known Member

Genz

Member

Genz

Member

2-strokeDD

Member

Genz

Member

2-strokeDD

Member

Genz

Member

Similar threads