J.D. 70A BACKHOE CYLINDER REPAIR

irwin · Jul 15, 2009

In the first picture, is this what your tractor looks like Curt? If so you have a 855 tractor with a 70a FEL. The second picture is a Deere 770 with a model 7 backhoe.

Is that the backhoe you have?

JFS2295 · Jul 15, 2009

Boy those cylinders on the JD7 hoe look like the ones on my ARPS hoe.

bennett2497 · Jul 16, 2009

Hi Kenny, those lines have threaded fittings. Thanks , Curt

bennett2497 · Jul 16, 2009

Hi Irwin,

Yes it looks like the one on the right ! Thanks, Curt

JFS2295 · Jul 16, 2009

Curt,

Do you have the spec's out of the manual for your bucket cylinder?

Piston DIA, stroke, retracted length, pivot pin DIA?

bennett2497 · Jul 20, 2009

Hi ,

I wanted to thank you guys for all the help. So what happened was , i rebuilt the one swing cylinder on the tractor. I took it apart and found a chunk out of the seal ( that must be the leak ). I replaced all the seals and o-rings. I put it back on the tractor and it started leaking ( what the **** ). Thats when i asked you guys about , if there was sealent around the gland ? To make a long story short, The line that crosses over to the other cylinder is an air passage, i thought it was a fluid line. So when i rebuilt the cylinder , i swung over the hoe arm and what happened then was, the fluid got transferred to the other cylinder ( in the air pocket ). So when i was done i swung the arm over and the fluid came with it and made the side i just worked on leak. So you were right about the sealent ( theres is none ). But in retrospect one side could be leaking and you wouldnt know which side it was, once the fluid gets behind the seals. Im think im a desent mechanic and i was stumped. I hope this story helps someone else with the same mishap ! Thanks , Curt

Wayne County Hose · Jul 20, 2009

That is interesting, that they would connect the 2 non-fluid sides of the cylinders. That way, no contaminated air gets into the system. If I were you, I would pull that line off and squirt some trally fluid in there, to keep the non-oil side of the cylinder lubricated. Glad you got everything straightened out.

kennyd · Jul 20, 2009

Glad you got it fixed

Eric_Phillips · Jul 21, 2009

Wayne County Hose said:
That is interesting, that they would connect the 2 non-fluid sides of the cylinders. That way, no contaminated air gets into the system. If I were you, I would pull that line off and squirt some trally fluid in there, to keep the non-oil side of the cylinder lubricated. Glad you got everything straightened out.

Isn't that what his problem was? He got oil on the non-oil side and since there is no seal it leaked.