MF 175 Injection Pump Timing

hearnc843

Member
I had a very leaky CAV injector that I resealed. I was very meticulous about the resealing process, photographing parts and putting things back exactly as they were. I tested the pump on the bench, by putting in some WD40, manually turned the pump and all four fired just fine. I put the pump back on the tractor, aligning the slot on the pump with the pin on the timing gear. I did pull the head on the pump, to change the o-ring, but I did not remove or change the cam ring from the head or remove the cam ring circlip from the housing.

I know the pump is working because I can bleed the lines all the way to the injectors when I crank it to start. It will not start, not even with a shot of ether in the intake.

My question- is there any way for the injector pump to get out of time? I noticed that the timing gear did have a little play to it, sliding forward an backward in the housing. Could it have slipped a gear tooth or two when reattaching the fuel pump?
 
That pump can't get out of time UNLESS the gear location pin is NOT in the pump drive hub slot. Gear also will NOT move enough in the case to jump a tooth. The two hydraulic head drive plate bolts are also offset. Also, WD 40 is NOT the fluid to use in priming the pump, TEST OIL is best for that, or clean diesel fuel..
 
Ok thanks. After much head scratching and going over the fuel pump again, I found the issue was my own stupidity. I pulled the fuel pump and realized I had the cam ring inside the housing flipped around. Whoops
 

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