Super 90 Injection pump leaking

I have a Super 90 that is leaking diesel fuel at the two pivot points on the injection pump where the throttle linkage connects and where the fuel shut off connects. Is there any easy fix or does this need to go to a diesel specialties shop?
 
Best in the long run to reseal the complete pump. I just finished a repairing CAV DPA pump for a Perkins AT4.236. While top can be re-sealed on engine, my forty plus years experience other leaks will show up soon after..
 
You could fix it yourself. I have done it a few times. It is MUCH easier to fix while the pump is off the tractor, but you can do it while it is on.
There are 4 O-rings under the injection pump cover...two on each shaft, that are probably the cause of your leak.
The cover comes off with the two nuts in the center of the cover
However the cover (on one shaft) is connected to the pump with a spring, that will fall off many times before you get it right....the spring ends MUST be put back into the same holes that they fell out of.
The two shafts come out by removing the nut, washer, lever and dust cover on top of the cover and the two shafts pushing down through the bottom, the O-rings will be on these shafts.
The hard part of reassembly, while pump is on the tractor, comes with the gasket between the cover and pump...you cannot be sure if the old gasket is completely cleaned off of the back side of the pump (Cant see very well back there) if the old gasket is not completely cleaned off and a new gasket is put on top....You WILL have diesel leakage from the join. PLUS that spring will fall off again many times before you get it assembled.
Then there is the problem of getting the shut off lever/shaft in the right place. There is a "fork" on top of the pump (Under the cover) the shut off shaft has a cam on it that moves the fork and shuts off, and turns on the fuel supply. The cam button must be in the fork.
All this is much easier to do with the pump off the tractor.
Pump comes off with three nuts at the front of the pump. You will have to remove all the lines, and remove the front cover plate right behind your lower rad hose. There are three bolts that hold the pump to the injection pump gear inside this plate. DO NOT lose one of the bolts inside the engine. The pump will come out the back....take note of the pin (On back of gear) that will time your pump when you re-assemble. The injection pump gear will NOT move in there so as to get out of time, but dont try to move it in any case, just leave it in there.
You can then repair the pump much easier on the bench.
While it is out, I would recommend changing the front seal in the pump. You will need to remove the hub that the gear was on and under there will be a seal that may at some time begin to leak and pump diesel into your crankcase.
I hope that these instructions are fairly clear? It is hard to explain something from memory, and put it into legible sentences.
I may have missed something there, but I am sure the tractor gurus will correct anything that I have left out or completely messed up.
If you decide to change the front seal...it may be no longer available...I think I may have one here, as well as the gasket and O-rings.
Good luck, Wayne
 

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