Ford 770B Loader issue

PaulT1966 · Jul 13, 2015

Gentlemen, I purchased a Ford 1510 (mid-late 80's) in March of last year. Had one bucket cylinder repaired about 2 months later. The other one seemed to be newer by the fresh paint & part number stickers, but no idea it's actual age. This year, my bucket has been dropping on it's own, & the issue is getting progressively worse.
My first thought was the control valve, but I don't see any seals along the shaft to let fluid pass, only at each end to seal the unit.
Could it be that one cylinder had a bad seal and caused the other to start leaking due to the additional stress?
Is there anything I'm missing in troubleshooting?

Fawken · Jul 13, 2015

PaulT1966 said:
Gentlemen, I purchased a Ford 1510 (mid-late 80's) in March of last year. Had one bucket cylinder repaired about 2 months later. The other one seemed to be newer by the fresh paint & part number stickers, but no idea it's actual age. This year, my bucket has been dropping on it's own, & the issue is getting progressively worse.
My first thought was the control valve, but I don't see any seals along the shaft to let fluid pass, only at each end to seal the unit.
Could it be that one cylinder had a bad seal and caused the other to start leaking due to the additional stress?
Is there anything I'm missing in troubleshooting?

It only takes one cylinder leak on an FEL to affect the other one because they are linked hydraulically with a manifold.

J_J · Jul 13, 2015

The spools are a precision fit and can wear, causing the cyl fluid to escape.

The cyl seals can be worn allowing fluid to bypass.

There are test for each.

PaulT1966 · Jul 13, 2015

Fawken said:
It only takes one cylinder leak on an FEL to affect the other one because they are linked hydraulically with a manifold.

Ack! I didn't even think about that! Thank you Fawken!

PaulT1966 · Jul 13, 2015

J_J said:
The spools are a precision fit and can wear, causing the cyl fluid to escape.

The cyl seals can be worn allowing fluid to bypass.

There are test for each.

Is there a special gauge needed for this? How many PSI are we looking at?
Thank you for your response J_J

J_J · Jul 13, 2015

You can test one cyl at a time by removing the hose from the base end. Cap the other hose to the other cyl.

Retract the cyl and see if there is a continuous flow from the base end port.

If the cyl test good, and the lift arms still drop. then the valve spools are leaking internally.

A hyd gauge in the hyd system is always good to have.