Ford 4000 diesel

[Budlight2121]

Good afternoon everyone, I have a ford 4000 su with the 201 3 cylinder diesel engine. I replaced the injection pump, injectors and fuel filter. Tractor ran great. About 4 months later I noticed a misfire at higher rpms, I would say at about 1400 to 1500 rpms is when it starts. I did a compression test and all 3 cylinders where 360 to 380. When bleeding the injectors I noticed the center cylinder looked like it wasn't getting the same amount of fuel, I checked after it was running and definitely not as much as the other 2 cylinders. At higher rpms it was the same low fuel and not a big difference in how the tractor ran.
Thanks for reading and any info will be helpful
Mike

 

[Bern]

Sounds more like a timing issue to me. Loosen the pump and advance it a few degrees and try it again. If the misfire goes away, you then need to figure out what inside the pump is causing the issue.

To advance the pump you want to rotate the top of it away from the engine, towards you.

 

[Dieseltech]

There are SOME CAV DPA three cylinder pumps that are phase sensitive with relation to the vane pump rotor blade slot to the rotor outlet port. Sometimes several blade rotors need tried to find the best one to prevent the light load/unequal delivery problem. Does not affect four or six cylinder pumps, only three cylinder pumps.