JD 955

[Bridges]

Hello all new member here.

I Recently inherited a JD955 with backhoe. It's a nice tractor in pretty good shape, only has 520 hours on it.

My question is with the backhoe. In a short period of time the bucket starts to drop and I say with in an hour the bucket is on the ground. I remember when the backhoe was first bought it never dropped. I think over the past 3 or 4 years it started dropping and now it seems to drop to fast in my opinion.

I haven't noticed any leaking lines until today when one popped on me. I moved the lever with the hose off and a lot of fluid shot out, so I guess the pump is working good. There is a spot on one hose where the covering is worn off but that doesn't look like it is leaking.

Any ideas? It's a bit annoying when working I need to pull the bucket back up.

Thanks in advanced for any help!

 

[RoyJackson]

My first guess would be the cylinder (on the main boom) is leaking internally. I'd get a kit and repack it.

 

[kennyd]

As Roy said, it's either the internal seals in the cylinder, or it may be that particular spool in the valve witch are generally not rebuild-able.

There are ways to check the cylinder seals, like pulling the hose off one side, then operating the spool (lever, control) that feed the other side of the piston and see if fluid comes out of the cylinder past the seals.

BE VERY CAREFUL though, hydraulic fluid under that much pressure can pierce the skin instantly, and cause very bad things to happen in your body!

 

[kennyd]

Oh, and WELCOME to TBN

 

[Bridges]

I never would have thought of the cylinder. The grease fitting on it doesn't work either.

Is this a difficult job to do?

Thanks!

 

[kennyd]

Exactly which cylinder are we talking about?
The main problem is dealing with the size and weight if it's the boom cylinder, and the nut that holds the piston seals is usually torqued to hundreds of foot pounds. Seal kits are usually about $50.00 or so...

Do you have a local hydraulic shop in your area? You may want to go talk to them...

 

[Bridges]

Yes it's for the main boom. Would I have any problems if I was to take the cylinder off to bring to the shop? Like what position should the boom be in and such. You would want the piston all the way in right?

 

[kennyd]

Yes, you want the fully retract the rod into the cylinder, that way it's easier to carry (not as long), there is no danger of damaging the chrome on the rod, and most of the fluid will be out off the cylinder.

A shop will be happy to just take just the cylinder, it's less work for them!

Remember it still might be the valve...

 

[Bridges]

I'm actually not even seeing a piston for the boom. I'm looking on jd parts for the 7 backhoe model right now.

I see a piston for the bucket, dipper stick, swing motion and the stabilizer.
I will have to trace the lines tomorrow to see whats up. But it has to use a piston right?

I did see a kit for the values so that's good news there.

 

[Bridges]

Oh i see, It's there but it's hinding in the boom, don't me..