Bill Radford
Member
A couple of months ago I did the hydraulic cover service on my 641. I cleaned the sump thoroughly and replaced the fluid with CNH 134.
The lift is strong now and works properly. The "bobble" is almost completely gone.
The problem is that the pump is making a lot of noise now. The tractor sounds like a diesel.
I bled the system by screwing a barbed fitting into the bleed port and running a hose to the sump fill port under the seat. I cranked it up and allowed it to run for 15-20 minutes. No bubbles in fluid at all.
I can lift an implement and the noise disappears while the lift is going up and resumes when the implement is raised and held steady.
I can hear the clattering in the valve end of the pump and can pretty well isolate it there with a mechanic's stethoscope.
I removed the proof meter adaptor and checked the 7/16 bolt on the pump gear for tightness. I managed to snug it up very slightly, but there was no change in the noise.
The lift functions well as it is. Is there any risk of damage to the camshaft or other internal engine parts to continue running the tractor?
Please advise as whether to rebuild the pump or what else I may need to do. Tractor runs great, have adjusted valve train to specs last year when I had hood off.
Thanks a bunch in advance.. I have searched the site but have found only bits and pieces of what I need to know.
The lift is strong now and works properly. The "bobble" is almost completely gone.
The problem is that the pump is making a lot of noise now. The tractor sounds like a diesel.
I bled the system by screwing a barbed fitting into the bleed port and running a hose to the sump fill port under the seat. I cranked it up and allowed it to run for 15-20 minutes. No bubbles in fluid at all.
I can lift an implement and the noise disappears while the lift is going up and resumes when the implement is raised and held steady.
I can hear the clattering in the valve end of the pump and can pretty well isolate it there with a mechanic's stethoscope.
I removed the proof meter adaptor and checked the 7/16 bolt on the pump gear for tightness. I managed to snug it up very slightly, but there was no change in the noise.
The lift functions well as it is. Is there any risk of damage to the camshaft or other internal engine parts to continue running the tractor?
Please advise as whether to rebuild the pump or what else I may need to do. Tractor runs great, have adjusted valve train to specs last year when I had hood off.
Thanks a bunch in advance.. I have searched the site but have found only bits and pieces of what I need to know.