Just got my injection pump rebuilt and new injectors. I had a popping out the exhaust before and i still have it. Any suggestions?
 
who diagnosed that? has nothing to do with pump or injectors. check your compression and look at valve lift. more so valve lift.
 
Diesel, got to try that myself. Both my 705 and my 97 stumble at high rpm and no load. I just figured my rebuild shop had the pumps leaned out at no load.
C
 
The pump shop CAN'T "lean out" the pump for no load, that's normal operation for ANY injection pump. At no load, the GOVERNOR controls the speed, and engine only gets the fuel it needs for that speed. Reason some engines "breakup/miss/exhaust pop" at high speed no load, ESPECIALLY with Stanadyne/RoosaMaster pumps is because they are constant end of injection designed pumps, variable beginning of injection. The LIGHTER the engine load, the LATER the timing is because the plunger rollers strike the cam ring lobes LATER during rotation, RETARDING the running timing. At full load, rollers strike the cam ring EARLIER, ADVANCING the timing as more fuel is injected. CAV DPA rotary pumps work the same way. Problem is most noted on fixed phase/ no advance pumps. Inline pumps can be built either way, constant beginning/variable ending or constant ending/variable beginning, OR both depending on what engine builder wants.
 
Have you checked that the valve push rods
are in place? One of mine had a valve that
would stick and the push rod would come
out, then it sounded like a one cylinder
Jake brake.
 
No, if advanced too far engine will start harder, and power WILL actually fall off. That's why it's best to check on a dyno. Another cause of high speed exhaust breakup/miss is if the high speed no load is set too high. Happens most often on fixed phase injection pumps.
 
Has a Bosch Pump. All rocker arms move very close to the same. Timing is right on. One Exhaust valve was pretty loose. Have not started it since adjustment.
 

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