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Rebuilding an injector pump

Yesterday's Tractor Forums
I removed the valve cover and I looks like everything was timed correctly. But I discovered a new issue I have some bent push rods. What could potentially cause this?
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Could my injector pump be set too high and causing over revving? The pump says 2200rpm super 77 engines are rated for 1600rpm correct?

The valves still move so I don't think the key is sheared.

The engine never sounded like it got to extremely high rpm. but I could be mistaken.
 
A . M. Aitkins said:
Could my injector pump be set too high and causing over revving? The pump says 2200rpm super 77 engines are rated for 1600rpm correct?

The valves still move so I don't think the key is sheared.

The engine never sounded like it got to extremely high rpm. but I could be mistaken.
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2200 Is not too high IF THAT'S WHAT PUMP MAX SPEED IS SET AT. The Oliver 1550 diesels run faster than that with the same cylinder head type.
 
Fritz Maurer said:
How about some history on this tractor? Did you buy it like this or have your had it a long time and just started running bad?
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This tractor was purchased roughly 4yrs ago. The injector pump was never that great but the tractor always ran great . I just got tired of having to pull start it and then be careful how far I lower the throttle everytime I use it.
 
I don't see how it can be out of time and bend only half the push rods in the engine... I think we can rule out cam timing. If they had bent since you had it , there would be much excessive valve clearance as the bent push rod will be shorter. If there is no excessive clearance, that means someone was in there before you and adjusted the clearance with the push rods bent. If you had been running it for 4 years, and a valve stuck bad enough to bend a push rod, there is no way you wouldn't know about it, because that is not self-healing condition.

I would straighten the ones you have or procure new ones, then carefully roll the motor over near the timing marks , and observe the valve action... on either side of TDC, one should be closing and the other opening... in some motors this occurs simultaneously.
 
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A few years back guys were sure that a gas engine setting up for a few months with ethanol gas would cause valves to stick causing pushrods to bend.
 
So I put my old pump back on just to see if I was timing the new one incorrectly and now the tractor has a full range of throttle and is very responsive. Would that mean there's something wrong with the new pump?
 
A . M. Aitkins said:
So I put my old pump back on just to see if I was timing the new one incorrectly and now the tractor has a full range of throttle and is very responsive. Would that mean there's something wrong with the new pump?
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What have you done (to correct)about the bent push rods ?
Am I to believe, the engine starts better now with the old pump back on ,than before you removed it?

To quote your original post as per below:
Hello all I have a roosa master Injector pump that has pressure issues. I can't start the tractor without pull starting it and I can't bring the engine to an idle without it dieing. So I want to rebuild it but all the shops around me either don't want to mess with it or they want a high rate to work on it. So I thought I could rebuild it myself. the mechanical part does not worry me. But I'm not sure what all goes into recalibrating the pump.
 
John Deere D said:
What have you done (to correct)about the bent push rods ?
Am I to believe, the engine starts better now with the old pump back on ,than before you removed it?

To quote your original post as per below:
Hello all I have a roosa master Injector pump that has pressure issues. I can't start the tractor without pull starting it and I can't bring the engine to an idle without it dieing. So I want to rebuild it but all the shops around me either don't want to mess with it or they want a high rate to work on it. So I thought I could rebuild it myself. the mechanical part does not worry me. But I'm not sure what all goes into recalibrating the pump.
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No what I meant was it's just running better than with the new pump. Sorry I should have phrased it better.

the rods I think have been bent a long time so for now I'm just using the old ones to move the tractor when I need to. but I found new ones that I'm going to put in as soon as possible but I need to go pick them up.
 
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