Ford 4500 Control Hydraulics Screeching

[TroyFord4500]

Hey guys/gals!

Bought a 1966 Ford 4500 Industrial ... no hoe on it, but has the FEL ... after flushing the system twice, my hydraulic fluid is finally not milky! Issue I'm having though is the control are screeching ... plenty of power in the hydros but the screeching is annoying/concerning ... even after warming up, it still screeches ... any idea what this could be? Releif valve? Sucking air somewhere? what are some ways to test for different issues ... any and all help would be awesome

 

[TroyFord4500]

I should add that the controls run perfect at first until the system warms up ... then they start making noise?

 

[City Farmer]

Usually the squealing is the pressure relief letting go. Crud gets in there when it opens and never completely closes again.

1)Does the loader valve have the self leveling feature? If it does, make sure the knob is in or out all the way.
2)Have you checked the pressure setting yet? If it’s to high, I guarantee it will bend and crack the loader arms.
3)have you cleaned the filter and inspected the pressure relief? Most of the time the PO will put to many shims in there.
4) Drive with the bucket raised, 2nd at 900rpms or so, then drop the bucket as fast as it will go. You’ll hear if the pump is loading the engine......back pressure.

On my 4500, the only thing that can hold the rear down is the BH dipper extended all the way out.

 

[TroyFord4500]

Thanks for the info! it does not have self leveling, does have float tho ... my controls have 3 levers ... 1 for loader up down, 1 for bucket control, and the 3rd im guessing would be for the hoe if it had one but doesnt? I"ll try all these things, I've tried to order a new relief valve for it and just try that, but I cant find anyone locally or online that has the one I need for mine. Can I plumb in a different relief valve? I was told it could be the check valves also, but was advised not to mess around with these unless I was a "professional"?? From what I've read the relief valves on this is either 1900 or 2200 ... when i tested it yesterday on my 3rd non used levers, it came up around 1800.

thanks for all the info!

 

[RickB]

Did you change the filter?

 

[TroyFord4500]

Yes sir ... I値l check it again this weekend but it should just be the large round filter up in the nose correct? The other 2 spin on filters are 1 for motor oil and 1 for the trans/3 PT right?