Farm Equipment - 49 wd hydraulic pump pressure

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49 wd hydraulic pump pressure

Printed From: Unofficial Allis
Category: Allis Chalmers
Forum Name: Farm Equipment
Forum Description: everything about Allis-Chalmers farm equipment
URL: https://www.allischalmers.com/forum/forum_posts.asp?TID=208135
Printed Date: 10 Sep 2025 at 9:39pm
Software Version: Web Wiz Forums 11.10 - http://www.webwizforums.com

Topic: 49 wd hydraulic pump pressure

Posted By: G226WD
Subject: 49 wd hydraulic pump pressure
Date Posted: 10 Sep 2025 at 3:18pm

Hi everyone say ive got a 49 wd the pump has been in a cardboard box for a few years and I put it back on just recently pump says 1800psi then 1500psi then now its 1000psi i replaced the long small spring the one for high pressure the old one made the pump chatter when i engage it id like to know about the shims on the top as well i want to get just under 3000psi if i can need a little help thanks

Replies:

Posted By: Allis dave
Date Posted: 10 Sep 2025 at 4:21pm

Get a WD or WD45 service manual. It explains the pump very well. I rebuilt mine about 12 years ago.

You need to pull out all 4 of the check valves on top and make sure the springs are good. I think 2 of mine were wore through and I replaced them all and also reseated the balls into the seat. Once that is done and all your orings are replaced. Then you can see where your pressure is at and start adding shims to the unload valve if needed.

Posted By: G226WD
Date Posted: 10 Sep 2025 at 5:02pm

can i do this while the pump is on the tractor also where in the pump are the orings you are refering to.

i have some parts and pieces for the pump here havent had it mind in pieces in a while part numbers would help i do not have a service manual thank you

Posted By: G226WD
Date Posted: 10 Sep 2025 at 7:16pm

is this what your talking about? part no 70224670 ?