MEP-002a possible Injector Pump Issues

[Boonies]

(1) MEP-002a possible Injector Pump Issues | SteelSoldiers
After finding and doing the governor repairs mentioned above, the generator ran really great. I have used it several hours per day since then with no problems until today.

It will start now, but runs really rough and cannot handle any load. Earlier in this thread, Ray70 suggested loosening the fuel connection to each injector, one at time, to see if one injector was firing or not. The test was successful then and both injectors were firing. It was after this that I found and fixed the governor issues. So, today I tried the same injector test again. It is only running on one cylinder, the one farthest away from the blower fan. No fuel at all is getting to the other injector. I can completely loosen the fuel connection to that injector when the generator is running and there is no fuel coming from the injector pump at all, not even a dribble. The fuel pump is working since fuel is getting to the one cylinder so it seems obvious it is the injector pump that is not working. When working on the previous issues I determined this machine has a Bosch IP not Ambac. Someone mentioned that the bosch are either very difficult or impossible to repair. Is that true? Also I thought I read that replacing the IP with a new one is a more difficult and involved process. This IP has had a very small fuel leak for a few months around fuel arm that connects to the governor linkage. I can’t tell if it has gotten worse or not because I can’t really run the machine.

Do you agree with my conclusion that IP is dead? I feel nervous about doing an IP replacement because I have never done anything like that, but have succeeded with many other repairs I have never done before. Any comments or suggestions?

 

[Guyfang]

Where did you loosen the Fuel line? At the Injector pump? Or at the injector nozzle??

 

[Boonies]

At the nozzle. I had the connector completely unscrewed. The pipe was still being held in place by the connection to the IP, but it was loose enough to jiggle around and no fuel came out at all. I loosened the other side and when I got it only partially unscrewed fuel was spraying out of it. I will go out right now and completely take off the fuel line on the bad side and report back..

 

[Boonies]

I removed the fuel line and generator would not start. A small spurt of fuel came out the IP every revolution of the engine. I put the line back in and it started again but still running really rough. I have an old nozzle. I will go put that in and see what happens.

 

[Dog Breath]

Correct me if I’m wrong guys here is my thought

When checking for fuel out the injector line manually pull the linkage at the IP up to full throttle and see what comes out of the injector lines. This will give you full flow from the pump. At idle not much comes out of the lines.
I have an ambec pump for an 002 that should work Or for parts

 

[Dog Breath]

I also have 2 new 002 engines in the wrappers from the rebuilder if needed

 

[Ray70]

If the injector line was loose enough to juggle around, it was definitely disconnected. I have seen cases where you loosen the nut but the line is stuck to the injector and still sealing off the fuel , but that is not the case for you. If the line itself is not physically clogged there must be a problem with the IP, but the only thing I can think of that could cause fuel at 1 injector and not the other is a broken key in the plunger ( which is irreplacable unless you find a good used Bosch pump ) This would prevent the IP from rotating ( which is how it directs fuel to each cylinder ). The only problem with this theory is that the 1 cylinder that is firing would theoretically get 2x more fuel pulses than normal and the timing of 1 would be way out of whack, at the end of the exhaust stroke/beginning of intake stroke.

DogBreath is correct that only a small drip should come out with each revolution, so if you have fuel spraying out of 1 line and virtually nothing out of the other line, perhaps the IP drive key is in fact broken??

Are you saying that with the suspect line removed and only the "Good" injector attached the engine would not start? That would seem to indicate the suspect one is actually working.

You could try removing both lines at the IP and crank it over and see if you get equal drips from both ports.
When cranking to start the IP automatically goes to full throttle, regardless of where the throttle knob is set.

You can find several threads, some from me, about the Bosch pump and yes, it is non-repairable if certain components are broken. The seals are the same as the Ambac and the throttle assembly is too ( yours is currently leaking ) but the plunger, drive gear and a few other key parts are completely different and nothing is available other than used parts. I have quite a few parts, but the plunger is the most common failure point and none are available.

Installing an Ambac pump is really not that bad but you need to determine which size timing button you need and then locate that button for sale. 99% of the time you need a #14 - #16 but those are getting very hard ( but not impossible ) to find