PLEASE HELP!!!! Hydraulic pump leaking,....... again!!

[brokenveteran]

Please bare with me guys as I am new to this, I have been reading your threads for information for a while but this the first time I am typing asking for help, and I need it!
I've got a Ford 3000, the hydraulic pump started blowing hyd fluid between the pump body and pump cover on the top quite hard. I bought a rebuild kit and replaced the gaskets, springs, balls and guides, checked everything over to ensure all was ok, reassemble, put it back on the tractor, checked the fluid level, bled the pump and all was great!! Time to finally get back to Bush hogging the fields. (4 acres of my yard) I got only 15 minutes into it and on the way up the hill I looked down to notice it was leaking again. Not the same as before, it wasn't blowing out at full pressure from the top, this time it was a steady constant stream out the bottom. So I've got it all takin apart again on my work bench all pieces cleaned and dried, I am going to buy new gaskets again one of them had a very small nick in it. I did smooth off the pump body face as well as the exhaust valve plate rear face, they are much smoother and level.
So all that being said, before I go and reassemble it again and quite possibly get the same outcome, is there something more I should check or do, could it be too high of pressure causing it? Would the exhaust valve plate be bad? Could it be getting plugged up down the line in the differential stopping the flow to where it builds up behind the exhaust valves and blowing out through the seems? Should I JB Weld the heck out of it and hope for the best? Lol. I am at a loss and at my wits end with the constant issues that keep arising. PLEASE HELP!!!

 

[kencunningham]

Check the bearings, if they are bad the seals dont stand a chance.

 

[Stimw]

All hydraulic circuits MUST have a relief system because if they get "Dead Headed" something Will break! The relief controls the working pressure.
If you can find the relief valve and check it for sticking or being able to adjust it.
If you can "T" in a high pressure gauge and confirm the working pressure.

 

[brokenveteran]

Thanks for the advice guys!
kencunningham: when you say check the bearings, which ones exactly are you talking about? On thw exploded view of the pump there are #'s- 13 (needle bearings), 16 (thrust bearing), 19 (bearing cone and roller) and 22 (needle bearing). Now these are all in the front section of the pump in the drive housing #6 to the pump body #24 which is all prior to the gaskets. Do I need to be looking at all of them again?

Stimw: right now the only material I have is the "FO-31 SHOP MANUAL" I did however today order the full repair and service manual (800+ pages) that should be here soon. I did aircraft hydraulic systems in the military amoung many others so I have a leg up on understanding systems, but,... until I receive that manual without tearing into differential housing and the hydraulic lift compartment which I would rather not do if it is by some chance exterior somewhere. Unless of course you happen to know where this is located??

 

[DLTTrekkers]

Best option is to replace pistonpump with a geartipe pump

 

[brokenveteran]

Are they interchangeable? Do they install at the at the same attachment point, where the gear that runs off the cam, and the hydraulic lines? As well as compatibility of PSI? I only ask because I have never heard of or thought of interchanging piston type to gear type.

 

[oldnslo]

typically a gear type pump will not be a direct interchange with a piston style pump. Drive shaft and front mount could be the same but 99% of the time the ports will be in different locations. I believe you need to do some trouble shooting to try an determine what is causing your current pump to fail. I don't see parts breakdown but usually when pumps start to leak externally it is from excessive pressure.

 

[brokenveteran]

That's what I as well as some other guys helping me on this issue have been thinking, it seems almost like stuck valves, or the the filter is completely clogged up, or (in my thoughts) the the pressure relief valve is stuck closed not releasing the overload of pressure causing it to find the path of least resistance, which just happens to be the gasket seal on the pump. :thumbdown: I do plan on breaking into the top of the differential and check all seals, o-rings, valves, , change fluid, etc.....

 

[banjodunn]

G'day did you replace the seal on the outlet pipe? I have seen these leak when reused.
The gear pump is interchangeable but IIRC the pipes have to be modded to fit, I have only had to replace them when pump output was down, see if you can PM soundguy here on the forums as he is very knowledgeable on all those ford hyd systems


Jon

 

[brokenveteran]

Jon, how do I "PM" ???? I have read many posts with soundguy giving advice, I have actually been hoping (since I first posted this) that he would read it and jump right in.