I have a 750 combine with a Delphi CAV injector pump. The problem begin as a hard to start issue and at times would surge as though it was not getting enough fuel. I thought the primary fuel pump was going out so I replaced it with an electric fuel pump and replaced the filters, and bled. I bled the filter assembly and the two vent plugs on the injector pump, according to the manual. The problem seemed to go away, but then did come back intermittently. More recently, the engine would almost die for lack of fuel, but if it set for a few minutes, seem to run fine. Now it’s at the point where it will start and run for a few seconds then die.
While it’s running for a few seconds I opened up the bleeders to see if the volume of fuel was sufficient. Out of the fuel filter bleeder, it comes out with quite a bit of pressure and volume. When I open the upper vent plug, it also appears to be coming out with pretty decent volume and pressure and is still coming out when the engine quits. When I open the lower vent plug, the pressure doesn’t seem as much as the upper vent plug and seems to have air in it. The fuel dies off from the vent plug and the engine immediately dies. I don’t see any air coming out of the filter unit or the upper vent plug, it seems foamy out of the lower vent plug.
Before I pull the injector pump, I would like some input from people that are knowledgeable about the engine and Delphi pump. Does the pump need to be rebuilt?
While it’s running for a few seconds I opened up the bleeders to see if the volume of fuel was sufficient. Out of the fuel filter bleeder, it comes out with quite a bit of pressure and volume. When I open the upper vent plug, it also appears to be coming out with pretty decent volume and pressure and is still coming out when the engine quits. When I open the lower vent plug, the pressure doesn’t seem as much as the upper vent plug and seems to have air in it. The fuel dies off from the vent plug and the engine immediately dies. I don’t see any air coming out of the filter unit or the upper vent plug, it seems foamy out of the lower vent plug.
Before I pull the injector pump, I would like some input from people that are knowledgeable about the engine and Delphi pump. Does the pump need to be rebuilt?
