MEP105A Generator Injector Pump

[fdilley]

I have a 1976 Libby built with a White Engines Ind, Hercules Engine Division engine model D-298-ERX37. I have all the electrical problems worked out of it and the engine turns over, but will not start. I have fuel to the injector pump but nothing comes out of the pump to the injectors. I measured the resistance of the shut of solenoid to be 14 ohms and I have 24 volts on it when cranking. I was told I could put 20psi of air on the last strainer to try and force fuel into the pump. But I don't want to damage the pump. Has anyone have a suggestions? Without removing it?

Thanks much

[Billy J Shafer]

Look for a screw on the side of the pump. It takes a 1/2 inch wrench to open it. It is the bleed off screw open it and if the engine has a primer pump,pump it until you have fuel coming out of the pump. Also you will need to open the injector lines on top of the engine. Turn the engine over untill you have fuel at the lines.Do not put air pressure into the pump. You could blow out all the seals and pumps are not cheap to repair.

[Raymond]

I have a Hercules D198 on a 1969 15 KW military (model slipped) but it has a day tank with a float in it. The shutdown system will stop it if the fuel gets low, I don't remember without looking at the diagram but make sure one side of the run coil is hot and the other is grounded. You should be able to hear a click as it pulls in. The pump is a Roosa-Master (Hartford screw co.) just like on the GM diesels and many (most) others that don't use Bosch, or CAV.

[Jim Rankin]

The return line to the tank could be stopped up. There is usually a fitting out the top of the injection pump that has a line from it up to a tee into the return line from the injectors that goes back to the tank.

The fitting in the top of the injection pump can be totally clogged with debris from the pump and not allow the pump to pump fuel.

If you have 24volts to the solenoid coil, make sure there isn't some safety system that interrupts the ground of the coil. The grounds can also be corroded.

[Billy J Shafer]

What Jim is talking about is a common problem. I forgot about the fitting on top of the pump. Most of the time it will let the engine start and then it will slow down and stop. If you remove it and find parts of rubber seals in it you will need to have the pump rebuilt.

[BTPost]

All the preceeding Posts are very good advice. If it were "Me", I would
rebleed the complete Injection System. First at the Input to the Injector Pump.
Second, at the Return Line out of the Injector Pump. Then Check the Shutdown
Solenoid to "MAKE SURE" it is actually pulling in to "Run" position,
while I cranked the engine. With that "Confirmed", then crack each of the
Injector lines, at the pump, and make sure that the Pump itself, is outputting
Fuel Pulses. Be careful NOT to get your appendiges anywhere near the
cracked High Pressure Injector lines, as fuel injected under your skin, is
a really BAD thing. Once you have confirmed that the Injector pump is
pulsing fuel to the Injecter Lines, retighten them at the Injection Pump,
and crack them at the Injectors, and crank the engine untill you have the
Fuel, pulsing out on each Injector. When this is confirmed, retighten the
individual Injector Lines at the Injectors, and you should get White Smoke
starting to come from the Exhaust. Hit the GlowPlug Switch, if you have one,
or blow some Hot Air down the Intake Manifold, (Politico's are really handy
for this step) and if the timing is correct, your engiine should start.

Bruce in alaska____ Diesel Engine Injection System Bleeding 101
............................

[fdilley]

I want to say thanks to all who answered my question. This injector pump has no primer pump on it. The only bleed screw that I could find is on the top near the shut off solenoid and it takes a larger screwdriver than I have (note: buy more tools!) I took all the injector caps off and found rust in all of them. I will check all injector lines and make sure the solenoid is working. Again Thanks much

Lee in Seattle

[oldtool53]

Originally Posted by fdilley

I have a 1976 Libby built with a White Engines Ind, Hercules Engine Division engine model D-298-ERX37. I have all the electrical problems worked out of it and the engine turns over, but will not start. I have fuel to the injector pump but nothing comes out of the pump to the injectors. I measured the resistance of the shut of solenoid to be 14 ohms and I have 24 volts on it when cranking. I was told I could put 20psi of air on the last strainer to try and force fuel into the pump. But I don't want to damage the pump. Has anyone have a suggestions? Without removing it?

Thanks much

Hi,
A Hercules (white) D298 is probably a Roosa Master (Stanadyne) model DB pump. It has no bleed screw. The bolt on the side (1/2") is a head locking srew. There is no internal passage to this screw hole for bleeding. Often confused with tho old C.A.V. (Lucas) DPA pump which does have a bleed screw in this same location.
You may have a stuck metering valve. This happens often to pumps that sit unused for long periods. If you are lucky you can get it freed up. Remove the top cover to access the metering valve.
You may also have stuck pumping plungers, which would require complete disassembly of the pump to correct. At the worst the head and rotor assembly may be seized. This is where it can get very expensive.
As for feeding the pump you will do no harm to the pump by pushing fuel with compressed air at 20 psi but you could burst the filter. Just use an electric fuel pump.

Mark

[Billy J Shafer]

Can you post a picture of the pump.

[fdilley]

Yes it is a Stanadyne type pump. I pulled off the timing line cover and some gunk came out. It seemed like pices of seals? I guess its time to pull the pump. I turned the crankshaft clockwise a couple of times, but never saw another timeing mark on what was rotating. So if you have any other suggestions, please let me know. It's real hard to see the timing marks on the drive gear and the idler. I don't want to have to pull the drive pulley and the timing cover if I don't have to. Thanks much.

Lee from Seattle

PS. My camera broke today just befor I could yake a photo.

[Billy J Shafer]

The timing mark is there just real hard to see. It will be better to line the marks up than to pull everything apart.

[John Schwiebert]

Is this a vertical or a horizonal mounted pump? Do get the lines in the pump to align before you remove it. Can not speek for the 4 cylinder Hercules but the 6 cylinder version of that same engine has some versions that are timed to number 6 cylinder instead of number one. Worse case, remove the valve cover and watch the push rods to see if you are on #1 or number 4 cylinder,compression stroke when the lines in the pump timing window align. If you have rust in the injector caps remove all four injectors and have those checked as well. Moisture is a diesel fuel system killer.

[fdilley]

Well guys I pulled the pump yesterday and I'm droping it off to Seattle Injector for repair. It had more wrong with it than I want to try to repair. So thanks for all the help and now I will wait for the repair.

Thanks Again

Lee from Seattle