Just picked up a case 500. It has not run for 5+ years but always parked inside. We were able to prime the system and lift pump seems to be supplying fuel but there is no high pressure to the injectors. Looking inside the timing cover the pump seems to be clean as a whistle. My guess is that the plunger may be stuck.Is there any tricks to free it up? We have not yet pulled the hydraulic head as we thought that maybe just having fuel to the pump may help. I have only ever worked on an ih pump so do not know much about these. One thing i am wondering is whether the gear inside the timing cover should rotate or is that just to afjust the timing of the pump. Any help appreciated.
- Thread starter Hattrick
- Start date
Dieseltech
Well-known Member
- Location
- Akron, Indiana
Most likely has a broken plunger, or at least the guide is broken that rotates the plunger. Best IT book that shows correctly how to remove/ replace the head is Oliver 66, 77, 88, 99 service manual..
In the Farmall MD the lift pump plunger will stick and you can sometimes free it up. I had to take mine apart. On the psb6a pump is it possible for the plunger just be stuck up if it stopped with the cam lobe up? Is the gear in the timing window supposed to rotate. Mine is not turning. If i take the hydraulic head off can it be replaced as an entire unit? Obviosly i would be able to see what is going on.
Dieseltech
Well-known Member
- Location
- Akron, Indiana
Most likely the plunger is broken and you will have fun finding a good head. Last Massey-Harris PSB I fixed told the owner bring any parts pumps you have, needed parts from 3 to make one work..
Hattrick:Take the cover off that is above the transfer pump, it is right below the head on the side of the injection pump. There is a lever behind it with a rod attached that you should be able to move to the left and right. If it doesn't move it will need to be freed up. When the throttle is opened it moves one way and the other way when the throttle is closed. It controls the amount of fuel going into the head. Spray plenty of wd40 where it pivots and gently try to move it with a pair of plires. If the lever moves we'll go to the next step.
Hattrick: If the lever moves, I agree with dieseltech. The plunger was probably stuck and it twisted off #25 shaft in the pump. You will have to remove the injection pump and take the two screws off the cover on the bottom of the pump and the gear #28 and the broken shaft will fall out.
The rod linkage that you are referring to is free. It looks like the #28 gear is the one you can see in the timing window.it does not appear to rotate but was not sure that it was supposed to.i am still curious if the plunger could be just stuck in the up position or if that is not possible.
The gear you are referring to is the top gear of #25, and the bottom gear is where they twist off if the plunger is stuck. It is a mechanical connection to the pump plunger, and the weekest link, the bottom of shaft #25 will break. It has happened to me many years ago. The only way to prevent it is to remove the pump before cranking the motor and see if the input shaft of the pump will turn. It's a lot of extra work, but if it is stuck, it will usually free up with WD40, and working the shaft back and forth, just don't force it. Your quickest fix will be a used pump.
Untitled URL Link
Untitled URL Link
Similar threads
We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.
Copyright © 1997-2024 Yesterday's Tractor Co.
All Rights Reserved. Reproduction of any part of this website, including design and content, without written permission is strictly prohibited. Trade Marks and Trade Names contained and used in this Website are those of others, and are used in this Website in a descriptive sense to refer to the products of others. Use of this Web site constitutes acceptance of our User Agreement and Privacy Policy TRADEMARK DISCLAIMER: Tradenames and Trademarks referred to within Yesterday's Tractor Co. products and within the Yesterday's Tractor Co. websites are the property of their respective trademark holders. None of these trademark holders are affiliated with Yesterday's Tractor Co., our products, or our website nor are we sponsored by them. John Deere and its logos are the registered trademarks of the John Deere Corporation. Agco, Agco Allis, White, Massey Ferguson and their logos are the registered trademarks of AGCO Corporation. Case, Case-IH, Farmall, International Harvester, New Holland and their logos are registered trademarks of CNH Global N.V.
Yesterday's Tractors - Antique Tractor Headquarters
Website Accessibility Policy