JD 448 Backhoe lost power

[Razor5621]

Put my 448 backhoe back on my JD3320 after tilling this spring. It was working great last fall. Tried to dig my first hole this year and the arm on the backhoe has no power. The bucket at the end of the arm seems fine but the arm won't pull dirt.

I disconnected the hydraulic lines and cleaned them but they were pretty clean anyway. The hydraulic fluid is at the right level and looks pretty clean.

What else should I be looking at before I haul it to the shop? I'm not an expert at all so if there are any easy things to check I'd love to learn how to do it to save some $$$.

Is there a good (free) manual online I could refer to?

TIA

 

[TractorTech]

Sounds like the dipper (arm) cylinder is leaking internally. Can you lift the dipper in the air and if so, will it hold there? This is the only other test besides trying to get it to dig that would confirm that the cylinder itself is the problem.

 

[Razor5621]

It does lift, but slowly.

If that is the problem, do I need to replace the entire cylinder or is there a ring or gasket that can be replaced?

 

[TractorTech]

There is a seal kit LVA11358, is about $135., but if it is leaking internally, I don't think the kit includes the piston seal and wear rings. The piston, LVU12341, is approximately $205.

 

[oldnslo]

Do all other functions operate with full power? Be a little unusual for a cylinder to totally fail while just sitting but possible. Can you put that cylinder in a position so weight of machine is trying to extend the cylinder? If does it stay in position or extend?

Can you see the linkage from the joy stick to the valve spool? If yes with the machine off move two or three functions and compare the spool travel. They should all be very similar. Possible something got in the linkage and is limiting the spool travel.