Hyraulics on 3pt not working.. jumping/not lifting on ford 1900. Please Help

[dustyfontenot]

I just bought a 1981 Ford 1900 tractor. I did a full service. I drained the hydraulic oil where the filter is, the rear diff plug, and the transmission plug, then I cleaned the filter which surprising wasn't that bad. I also did engine oil and fuel filter. Well the first day everything worked fine for 3 hours. But on the second day the hydraulics on the 3pt on rear started lifting slow and started JUMPING when lifting up and will barely lift. I don't see any leaks.
Also the pump sounds like its cavitating. I used a universal hyd oil( Super S).

Any help will be much appreciated!!

 

[BukitCase]

Welcome to TBN - Did you re-check hyd levels AFTER you ran it for awhile? Symptoms sound like low level, some machines can get a LOT of air when doing full service, it's always best to "exercise" every circuit several times after filling, then re-check... Steve

 

[dustyfontenot]

Yes, I have checked multiple times. I even loosened the smaller diameter piping on the discharge of the pump (the big bolt on the front right of the tractor) I turned over engine to crank it for like 2 seconds and it sprayed about a 1/2 gallon of hydraulic oil. I then killed it and tighten it back up.

 

[dustyfontenot]

so after that I added more oil to fill it back up.

 

[Sawyer Rob]

Sounds like air is trapped in the system some place...

SR

 

[dustyfontenot]

Any tips on bleeding it?
I did some research on the Super S AGRI+PLUS hydraulic oil and it says not recommend for models later than 1974. So I will drain it, and refill with a different oil and maybe something will change.

 

[Jsheds]

I had a very similar problem with my Ford 1910. It turned out to be the piston seal on the 3 point hitch lift cylinder. Maybe the oil change is a coincidence. The seal is an easy fix if that turns out to be the problem.

 

[dustyfontenot]

where can I order new seals?

 

[Jsheds]

I got mine online from Messicks.

 

[5030]

Word of caution... Cheap hydraulic fluid is just that cheap. I bet your fluid is an issue. Buy some not so cheap stuff and refill it. Take the cheap stuff and use it for fire starter.