1986 3cx 1550b hydraulic pump question**** UPDATE*** Someone PLEASE help

[newfjcb]

Hey, I'm new to the board here and have a question about an older JCB 1550 backhoe I purchased. It has a gear driven hyd pump mounted up front that runs by PTO off the engine, The problem is the pump shoots hyd fluid whenever I operate the backend of the hydraulic system,( the hoe and rear stabilizers). I can use the front bucket and it doesn't seem to do it but I don't bottom out the front bucket when i try. I cleaned all the dirt/oil off the pump and can see where it seems the fluid is coming out. It looks like its in the back half of the pump where it mates to the main body. All the yellow paint is wire off due to the high pressure. Any ideas what the problem could be?

[Jeremy Rowland]

Hi Cory, welcome to the site I'm sure somebody on here will be able to help you with your problem.

Jeremy

[Mark.Rive]

Hi Cory, welcome to the forum. The pump on your machine splits in half for servicing, from your description it would seem the shaped o-ring that seals the 2 halves together is blown There is a seal kit available. If the input shaft seal is perished the oil that leaks out would usually be shot around the machine in a nice circle as it flies off the rotating pto shaft! I have part numbers for JCB products from 1975 on, if you let me know the serial number I can get you the part numbers etc. Cheers Mark

[newfjcb]

Removed pump, split it apart and found the oring between the 2 halves of the pump blew out, right where I expected. I put new seals, o-rings in and reinstalled the pump and it worked good for about 20 hours and the damn seal blew out again. Lots of power in the hydraulics when it did work, What could be causing this excess pressure in the system. Anyone know, any ideas, I recently bought this machine and it was like it whne I purchased it. I also noticed a new line goin from the pump to the bucket dump lever. So maybe before I bought it it blew the hose as well.

Where would the pressure release valve or bypass vales be located. The fluid is nice and clean and the filter has been changed recently. Any suggestions would be appreciated, I`m trying to get this running again so I can clead my land to build a new home.

[actros]

hi everybody am new here i am from JORDAN i have a 3cx-4 it runs more than very good but before 2 days the main pump ( at the front ) didn't give a high presure i loosen the outlet hose but the hydro oil was gitting out as a leak ,not in a high presure. SomeOne please HELP

[Mark.Rive]

Hi Nael, welcome on board. Have you checked the pick-up strainer? First place to start is here. If its blocked you will have low pressure. Cheers Mark