Hydraulic Pump - what should I be thinking?

[DonTheNewby]

51 8n...

I dropped the pump to replace the slightly leaking gasket (and removed the cover as it was a rusted mess - to clean and paint).

As I think about it, the lifts would loose pressure if the tractor sat; say overnight and sometimes over several hours

I opened one of the chambers and noticed what appeared to be little slivers of silicone caulking... and opened the others but didn't see anything right off.

What is the most likely culprit when it looses pressure while sitting?

What should I be thinking to replace, if anything, while I have it out?

 

[R Geiger]

You should have looked for leaks before you dropped the pump of removed the cover. It could be the piston leaking or the pump valves.

 

[DonTheNewby]

(quoted from post at 14:46:53 07/18/21) You should have looked for leaks before you dropped the pump of removed the cover. It could be the piston leaking or the pump valves.

That probably would have been a good idea!

Shame I wasn't smart enough to ask first :lol:

 

[jimtrs]

(quoted from post at 15:20:56 07/18/21) 51 8n...

I dropped the pump to replace the slightly leaking gasket (and removed the cover as it was a rusted mess - to clean and paint).

As I think about it, the lifts would loose pressure if the tractor sat; say overnight and sometimes over several hours

Overnight, or even several hours is Good! None of these will hold up indefinitely. You got a problem when it drifts down in minutes, or less than a minute. Overnight, and you don't really have a problem.
By the way, other than testing reasons it's a good habit to NOT leave the lift in the up position when unattended.

opened one of the chambers and noticed what appeared to be little slivers of silicone caulking... and opened the others but didn't see anything right off.

s you've discovered - using silicone around hydraulics is a no no. That being said, if you've pulled off the side chamber covers, they now now need to be cleaned completely free of old gasket material, which is no easy chore. If you just removed the top chamber covers, may as well carefully remove the valves and clean this area really well. Careful to observe orientation and order of all parts.

What is the most likely culprit when it looses pressure while sitting?

robably a leaking lift cylinder - worn piston rings and/or badly scored cylinder.
But again, leaking down overnight is not a serious leak.

What should I be thinking to replace, if anything, while I have it out?

f it were me, and the lift is operating correctly and as you describe, I'd clean up the pump real well since it's out and re-assemble all.

Your other option at this point is to rebuild the lift cover and set all adjustments. If you're unfamiliar with this, you may not get back to where you are without a bit of trial and error. This may mean R&R'ing the lift cover several times. Don't be lulled into the thinking of well if I just follow the directions in a manual, all will be good. 70 years of use, abuse and wear, make the manual instruction adjustments not work very well.

 

[DonTheNewby]

(quoted from post at 05:43:37 07/19/21)

(quoted from post at 15:20:56 07/18/21) 51 8n...

I dropped the pump to replace the slightly leaking gasket (and removed the cover as it was a rusted mess - to clean and paint).

As I think about it, the lifts would loose pressure if the tractor sat; say overnight and sometimes over several hours

Overnight, or even several hours is Good! None of these will hold up indefinitely. You got a problem when it drifts down in minutes, or less than a minute. Overnight, and you don't really have a problem.
By the way, other than testing reasons it's a good habit to NOT leave the lift in the up position when unattended.

opened one of the chambers and noticed what appeared to be little slivers of silicone caulking... and opened the others but didn't see anything right off.

s you've discovered - using silicone around hydraulics is a no no. That being said, if you've pulled off the side chamber covers, they now now need to be cleaned completely free of old gasket material, which is no easy chore. If you just removed the top chamber covers, may as well carefully remove the valves and clean this area really well. Careful to observe orientation and order of all parts.

What is the most likely culprit when it looses pressure while sitting?

robably a leaking lift cylinder - worn piston rings and/or badly scored cylinder.
But again, leaking down overnight is not a serious leak.

What should I be thinking to replace, if anything, while I have it out?

f it were me, and the lift is operating correctly and as you describe, I'd clean up the pump real well since it's out and re-assemble all.

Your other option at this point is to rebuild the lift cover and set all adjustments. If you're unfamiliar with this, you may not get back to where you are without a bit of trial and error. This may mean R&R'ing the lift cover several times. Don't be lulled into the thinking of well if I just follow the directions in a manual, all will be good. 70 years of use, abuse and wear, make the manual instruction adjustments not work very well.

That makes a huge amount of sense based upon the position I've put myself.

Hopefully that is the last time I do something without asking first. But I guess that's one way to learn... jump in wrench first... for better or worse.

Thank you so much.