MEP-002a possible Injector Pump Issues

[Boonies]

I have spent many hours trying to adjust the governor. The manual says to adjust for maximum sensitivity without hunting. It says the speed should drop from 61.5 Hz no load to 60 Hz full load with no hunting. I am using a quality digital frequency meter, not the one the unit came with. The best droop I can achieve is 61.5 Hz to about 55-56 Hz. When I get this droop, it will hunt at no load. After adding approximately 1 kW load it will stop hunting. The hunting is not rapid like the manual says. It will run even for just about a second then act like it might die, but it dips and then revs back up where it was. Again, this happens about once per second. When I adjust the adjusting ratchet CW until the hunting goes away, the droop is 61.5 Hz no load down to about 53 Hz full load. I have had the generator 12 years and it has served us well. I never had any reason to measure the droop before, but I know it used to be much better, I just don't know how much. I don't know what the frequency used be over the full load range. I only know it is not good now.
The reason I titled this possible infector pump issues is because the injector pump has developed a leak. I am pretty sure it is where the rod that fuel arm that the governor linkage connects to goes into the pump. Unfortunately I can't remember if the governor issues started at the same time the leak started. Could such a leak in the injector pump cause the this problem? The leak is fairly small. If I clean the area up and run the engine, it takes about a minute before the first fuel drop drips off the bottom of the governor linkage. Then it will drip about one drop every 2 or 3 seconds.
I have read a few of threads on injector pump issues. Unfortunately, I have determined that I have the Bosh pump, not the Ambac.
I would greatly appreciate any help I can get with this. Thank You.

 

[Dog Breath]

I would get yourself an infrared temp gun and check each exhaust pipe for a temperature difference. A cool exhaust may indicate a dirty injector.

 

[Ray70]

Fuel leaking from around the throttle shaft assembly will not cause your issue. It sounds ( as dog Breath mentioned ) like a lack of fuel , possibly due to a bad injector, or maybe a bent governor arm.
One way to help figure it out is to manually push up on the throttle linkage while it is under load and drooping down to 56Hz or whatever. If the linkage is already maxed out ( all the way up ) then the governor is doing its best but engine won't rev up due to some other issue. ( probably fuel )
If you can manually increase engine RPM by pushing up on the linkage then the governor is not working correctly.
NOTE: it's not always just the droop setting. I've seen governor arms with the slightest bend in them cause these issues, same goes for the adjustment nut where the lever arm "Fork" attaches to the vertical extension rod.
Start by verifying that the engine and fuel delivery are ok. If so, then move on to the governor.

 

[Boonies]

Fuel leaking from around the throttle shaft assembly will not cause your issue. It sounds ( as dog Breath mentioned ) like a lack of fuel , possibly due to a bad injector, or maybe a bent governor arm.
One way to help figure it out is to manually push up on the throttle linkage while it is under load and drooping down to 56Hz or whatever. If the linkage is already maxed out ( all the way up ) then the governor is doing its best but engine won't rev up due to some other issue. ( probably fuel )
If you can manually increase engine RPM by pushing up on the linkage then the governor is not working correctly.
NOTE: it's not always just the droop setting. I've seen governor arms with the slightest bend in them cause these issues, same goes for the adjustment nut where the lever arm "Fork" attaches to the vertical extension rod.
Start by verifying that the engine and fuel delivery are ok. If so, then move on to the governor.

Thanks for the help. I am in a tight situation. I need the generator daily and don't have a lot of time to be messing with it. Also, I have never done any work with diesel injectors, injector pumps, or fuel systems so I am in a learning mode. I have another MEP-002A I use for parts. There are problems with the generator section but the engine seems to be good. It will start and run, but I cannot put a load on it to test it. On the one that I need to use I noticed that there is a lot of black gooey build up on the outside of the injector closest to the blower fan. Can I pull the injector off of the parts machine and install it directly? Should it be cleaned? What is the quickest way to do that? Do I need to do anything else? Any tips on how to proceed? Any gaskets or anything else I need? In the manual I only see one gasket. Can it be reused?

 

[Chainbreaker]

One quick thing might be to fill the last fuel cannister with a can of "straight Seafoam", crank to start & run shortly & let it sit a while, overnight preferably, with Seafoam sitting in IJ Pump all the way into injectors.

Restart next day & run for a while to see if any improvement. If there is any gunky restriction affecting IJ pump or injector(s) this might help dissolve it.

 

[Ray70]

Before pulling the injector, take 2 minutes and load it until it bogs, the push up on the linkage and see if engine revs up or not. That info is very important. Once that is done you can mess with the injector.
If afterward you want to swap the injector, there is nothing you can really do to clean it without taking it apart, but you can take it apart and try cleaning the nozzle and pintle fairly easily and without any special tools and without disturbing the current pop pressure setting.
On the gasket, it's really a 3 piece set. A thin fiber washer, a steel disc about 3/16" thick and a thin copper ring about 1 1/4" dia.
Quite often the steel disc and copper ring will stay inside the head and the fiber washer with either come off cleanly and stuck to the injector, or it may separate or tear. You can reuse it if not badly damaged, you can even use a thin layer of copper silicone if it does get slightly damaged, or you can purchase a new fiber washer direct from Cummins or on-line for $5-$6 each. PN is in the -24P manual for both the individual parts and the kit containing all 3 pieces.

 

[Boonies]

One quick thing might be to fill the last fuel cannister with a can of "straight Seafoam", crank to start & run shortly & let it sit a while, overnight preferably, with Seafoam sitting in IJ Pump all the way into injectors.

Restart next day & run for a while to see if any improvement. If there is any gunky restriction affecting IJ pump or injector(s) this might help dissolve it.

I just happen to have 2 full bottles of Seafoam. I have replaced the canisters on my machine with thread on filter adapters. Can I just pour the fuel out of the last filter and put seafoam directly into it?

 

[Boonies]

Before pulling the injector, take 2 minutes and load it until it bogs, the push up on the linkage and see if engine revs up or not. That info is very important. Once that is done you can mess with the injector.
If afterward you want to swap the injector, there is nothing you can really do to clean it without taking it apart, but you can take it apart and try cleaning the nozzle and pintle fairly easily and without any special tools and without disturbing the current pop pressure setting.
On the gasket, it's really a 3 piece set. A thin fiber washer, a steel disc about 3/16" thick and a thin copper ring about 1 1/4" dia.
Quite often the steel disc and copper ring will stay inside the head and the fiber washer with either come off cleanly and stuck to the injector, or it may separate or tear. You can reuse it if not badly damaged, you can even use a thin layer of copper silicone if it does get slightly damaged, or you can purchase a new fiber washer direct from Cummins or on-line for $5-$6 each. PN is in the -24P manual for both the individual parts and the kit containing all 3 pieces.

Thanks Ray70. I will do the linkage test first. Then I will try the seafoam Chainbreaker suggested. Then I will do the injector swap.

 

[Ray70]

I just happen to have 2 full bottles of Seafoam. I have replaced the canisters on my machine with thread on filter adapters. Can I just pour the fuel out of the last filter and put seafoam directly into it?

YUP, just be careful, the center of the filter is usually the downstream / output side, so anything you pour in will go unfiltered into the pump. Not a big deal in my opinion as long as no dirt gets in there. Another option would be to dump the fuel out of both filters, pour seafoam into the first, then let the electric pumps push the seafoam out of the first filter, through the 2nd filter then into the IP. It will probably get diluted somewhat with diesel, but it WILL get filtered by the 2nd filter. It's up to you...
This is similar to the whole " should you pre-fill your oil filter or not" debate. Personally I do prefill my filters!

 

[Dog Breath]

Your generator will run on straight sea foam
You can also get your tank as low as possible and add a gallon of sea foam. Run it and let it circulate with a load.