Hydraulic pumps

[Ed marr]

I have a Jinnah 284 tractor rebuild motor , but continue to have hydraulic pump problems , the pump blows
a seal seams like every few months, most hydraulic parts have been change except for the hydraulic steering cylinder any help would be appreciated

 

[Ed marr]

FYI, also live in north Idaho and would appreciate any help finding someone who knows of hydraulic works in jinma tractor

 

[oldnslo]

Are you blowing the input shaft seal out of the pump?

 

[JC-jetro]

If pump is overhauled and seal changed correctly and you continue having damaged seal then for sure you need to look at you Pressure relief setting, it might be set too high. it appears your pump is either dead heading or trying to maintain more pressure than it rated PSI. not familiar with your rig but you must have a location that you can put a liq filled 3000 psi to see what you are running your hyd at.

 

[Ed marr]

If pump is overhauled and seal changed correctly and you continue having damaged seal then for sure you need to look at you Pressure relief setting, it might be set too high. it appears your pump is either dead heading or trying to maintain more pressure than it rated PSI. not familiar with your rig but you must have a location that you can put a liq filled 3000 psi to see what you are running your hyd at.

If pump is overhauled and seal changed correctly and you continue having damaged seal then for sure you need to look at you Pressure relief setting, it might be set too high. it appears your pump is either dead heading or trying to maintain more pressure than it rated PSI. not familiar with your rig but you must have a location that you can put a liq filled 3000 psi to see what you are running your hyd at.

 

[Ed marr]

The shaft seal seems to be ok it’s the smaller seals that seem to blow maybe I will back pressure all the way down when not doing any lifting?

 

[rScotty]

The shaft seal seems to be ok it’s the smaller seals that seem to blow maybe I will back pressure all the way down when not doing any lifting?

If you use a guage good practice is to use a gauge with twice the PSI you might see. They all cost the same. A 5000 psi guage is typical. I like the glycerin filled type, but they do tend to freeze in cold weather.

When not lifting and no cylinders are working the pressure will back itself down to nearly nothing except for small occasional demands from the power steering.

 

[Tinhack]

If you're playing with pressure settings, you need a gauge.

Also check for a restriction on the return side--Bad hose to the tank, return hose too small or bad filter.

 

[Ed marr]

If you use a guage good practice is to use a gauge with twice the PSI you might see. They all cost the same. A 5000 psi guage is typical. I like the glycerin filled type, but they do tend to freeze in cold weather.

When not lifting and no cylinders are working the pressure will back itself down to nearly nothing except for small occasional demands from the power steering.

Yes I have a gauge and is old I will replace it and change filter after rebuild pump and go from there, the good thing is it’s easy to get too and replace rubber gaskets thanks for input

 

[oldnslo]

If you are blowing the seals out between the gear case and end covers you have an over pressure condition in your system and could potentially damage other components in the system

what is the first valve or item in the pressure line of the pump?