JD 2240 hydraulic pump sounds like a rock crusher

[mark vetter]

Hi gang, my 1979 2240 hyd. pump began groaning a month ago, so I changed hyd. filter checked screen and new oil. what began as intermittent has now grown to full time horrible grinding but with no loss of hyd function.coupling in good shape, I took inlet line loose to check flow of the gear pump and have good flow. will perhaps put a press gauge on to see what i got. I am ready to buy a new 8 piston pump with the symptoms I see and hear. This is a tractor with live pto,hyd pto brake, power steering. Tractor has lots of hours but now is kind of a backup unit. Should I be afraid of buying a new pump off ebay? I will be paying attention to all suggestions. Thanks.

 

[Tx Jim]

Does hyd sound change with pto engaged or disengaged? I'll suggest to test hyd's with power steering supply line capped off? Was there any debris in old hyd filter or on screen? With 3 pt raised,hyd oil at operating temp,engine running,look in hyd filler hole behind seat for moving oil which would indicate leaking rockshaft control valve seals.

Keep in mind since the mid 60's several JD closed center hyd pumps have been replaced only to determine that the original pump wasn't bad.

 

[mark vetter]

Took a few days to return to this project. I just today checked inlet press at front pump and was 120psi pretty steady. No debris in screen or filter. will check pto next. why isolate power steering? will do so and check rockshaft. thanks again for the tips.

 

[RickB]

Check the pump drive coupler and it’s bushings.

 

[Tx Jim]

why isolate power steering? will do so and check rockshaft. thanks again for the tips.

Power steering on JD tractors of this era have been known to blow 1 or more of the 6 large o-rings causing frt hyd pump to run out of oil & make noises.

 

[mark vetter]

Power steering on JD tractors of this era have been known to blow 1 or more of the 6 large o-rings causing frt hyd pump to run out of oil & make noises.

You certainly have a trove of in depth info on these tractors. If push comes to shove, would you consider it a poor idea for me to rebuild this pump in my shop, or just buy new?

 

[Tx Jim]

You certainly have a trove of in depth info on these tractors. If push comes to shove, would you consider it a poor idea for me to rebuild this pump in my shop, or just buy new?

I had my share of experience with closed-center hyd's because I was employed by a JD dealer from '65-'87 & served as dealer service manager from '75-'87. I'm going to state 1(one) more time """good hyd diagnostics need to be performed"""" before hyd pump is removed!!!!!!!!!!!!!! Whether hyd pump could be repaired successfully will depend on what's wrong with it.If piston bores are worn then pump isn't easily rebuild-able.

 

[beenthere]

would you consider it a poor idea for me to rebuild this pump in my shop

Yup, I think Jim is saying that. Having his experience on TBN means a lot to us, and that he, among many others, is willing to share.

 

[Tx Jim]

The ability to successfully rebuild a hyd pump depends on what's wrong with it AND how well the hyd system has been maintained since tractor was new. n another tractor site I frequent a very experienced JD technician that's operated his own repair business stated it's better to install new pump than rebuild the old one.


As I & others have stated before many closed center hyd pumps have been replaced only to determine the replaced pump was not the problem

 

[mark vetter]

The ability to successfully rebuild a hyd pump depends on what's wrong with it AND how well the hyd system has been maintained since tractor was new. n another tractor site I frequent a very experienced JD technician that's operated his own repair business stated it's better to install new pump than rebuild the old one.


As I & others have stated before many closed center hyd pumps have been replaced only to determine the replaced pump was not the problem

Thank you Jim, I am happy that this forum and you knowledgeable fellows exist. Right now i have the time to do diagnostics. I operated the pto which made no change. I then plugged power steering line and had no change. Pump doesnt make any noise till oil warms up. when wife operates 3 point I have oil raining down from control valve, on down travel, about a cup per stroke. No oil activity when not using control valve.
If you are not tired of my questions, care to suggest another test? Tomorrow I go to a Jd tech who went on his own and I trust. If I fail to make headway, at least I am much more knowledgeable now. I can read the schematic of the hyd system and make good sense of it. I used to be a machinist and built hyd valves and vane pumps. Also built carco winches and gearmatic winches. See ya.