squealing hydraulic valves

dingleberry · Oct 24, 2004

I have a 1982 Ford 1700 diesel 4wd. The tractor has a Ford FEL and a Ford 758 backhoe. The tractor has alot of hours on it. The hydraulic valves for the front end loader and backhoe squeal when activating the valve. When the attachments are not being operated there is no noise.(Pump and main valve seem okay) It is just the valves that operate the loader and the backhoe. any ideas??
Thanks

KiotiJohn · Oct 25, 2004

Look for any bent hydraulic lines as one possible cause. It's only happening with flow. Also make sure that all the quick connects are on tight.
Of course, the first thing is to assure that you have the proper amount of fluid, and that it has been changed along with the filters/ clean the screen.
Bleed air from many loaders by raising the bucket, operating all phases and putting it back down on the ground.
Let us know what happens.
I hope one of these will solve your problem. Let us know. John

ronjhall · Oct 25, 2004

I am not sure this will help.
When I installed 3 additional valves on my tractor one made a similar noise. Found that pressure setting was only about 500 psi. This valve is not power beyond. It is open center. Adjusted valve pressure closer to main relief setting of 2000 psi. Noise stopped. I believe with the lower setting most of the oil was being sent past the relief in the valve, causing the nosie.

dingleberry · Oct 25, 2004

I appreciate the ideas I will check into them....

KiotiJohn · Oct 25, 2004

</font><font color="blue" class="small">( Adjusted valve pressure closer to main relief setting of 2000 psi. )</font>
Cool. I hadn't thought of that one, but it makes sense. thanks, John

MMM · Oct 25, 2004

Does the return line go straight to tank or through remote? Remotes can cause problems like that. Give a little more info on how it's plumbed. Quite odd that both valves would be in relieef. Any QDs? I just had one mysteriously diconnect, but stay together. Blew out 2 sets of o rings on my loader valve before I figured it out. ( I have front pump with no relief valve. ) Do you have pressure guages in the system?