MEP-803A oil dilution/injection pumps

[parttime]

Im in North MS I picked up an MEP803A 2 years ago. It had 250 hours. I added fluids and new batteries. Everything worked as advertised. I have used it half dozen times for 2-6 hours over the past couple years without noticing any issues. Due to current ice storm in North MS I have had it running for 6 days straight. After first 24 hours I noticed a drop in oil pressure and the oil had increased way above full mark on stick.
I changed the oil and it was 2 quarts more than expected and more like diesel than oil. I have read about metering pumps leaking into crank case, or injectors being stuck open both of which can cause excess disel fuel in oil and staving the engine of needed lubrication.

Currently I am dumping the oil every 12-24 hours and refilling with rotella T4. Pressures are staying above 20PSI, the exhaust temps are front to back cylinders (150, 200, 250,250). I will need to continue for another week. My question is I dont have spare parts now, can the metering pumps be adjusted to normalise temps/fuel wash?

Does anyone else have real world knowledge of keeping this running for another week better than changing oil every day to eliminate the diesel washout? If the auxillary pump was stuck on and overflowed the tanks could this cause diesel in the oil?
Any real world emergent advise is appreciated. Thanks

 

[Guyfang]

You can adjust the metering pump by loosening the nut, (Item #1, not too much!) and turning the Metering pump with a wrench. But I do not think this is going to get you anywhere. It sound like the Pump is stuck open. Normally the Pumps are turned to the right until they are up against the push rod tube, like the picture below. One jug, only reads 150 degrees. That sounds like a place to start.

 

[parttime]

The coldest cylinder is closest to the fan. Its 100 degrees colder than the rest. That same metering pump is turned more to the left than the rest. While adjusting the pump should it be on or off? Can it be done on to listen to the rhythm of the motor? Direct message me and so we can discuss over the phone.

 

[87cr250r]

What temperature is the engine operating at? It needs to exceed 150 degrees F or it won't be able to evaporate unburned fuel from the oil. If the engine is operating at 150°F and you have an exhaust port temp with that temperature you've got a dead cylinder. If the injector is pumping fuel , you're getting fuel in the oil, and you don't have black smoke then you've got no compression in that cylinder.

You may be able to remove the injection pump for that cylinder, cover the hole, and run the engine as a 3 cylinder.

 

[parttime]

Running the normal 190 degrees on temp gauge. Its been in the 50-75% range throughout the week with surge when well kicks on. There have been periods of black smoke. I wonder if its lots compression in that cylinder and lost power. I plan to attempt to adjust that meter pump ASAP and recheck temps.

 

[Ray70]

Before you get too hung up on the front cyl. temp let me ask 2 questions:

When measuring the temp are you blocking the air from the radiator fan from altering your readings? If not, the fan often makes your temp on the front 2 cylinders appear lower than the rest, block it with a piece of cardboard and repeat the measurement.
2) how is the machine running? If you had an injector stuck open enough to dump that much fuel into the oil or a metering pump that far out of adjustment I would expect to see an issue with the exhaust color and I would expect the exhaust temp to be high on the offending cylinder, not Low, unless the cylinder is not firing at all.

I'd suggest searching around here, several months ago I think I recall someone with an 803 or 802 dumping fuel into the oil and I think the problem was a metering pump that was leaking internally, dumping fuel directly into the crankcase.

 

[parttime]

Thank you all for all of this information. Its been running for 7 days. Practically powering everything in my house except dryer/hotwater heater currently. I had the water hearer going yesterday but unpluggd it for added space heaters. It seems when all of the house space heatrs are on like 5 and the water heater is runni g, if the well kicks on that surge is too much. Currently its about 50% load without water heater with the surge from the well taking it up higher but not sure how high.
Without field experience im unsure of normal vs not so normal. The first 24-48 hours there was plenty of coal rolling smoke and that was when I had the loss of pressure and lots of diesel in the fuel. I've used plenty of fuel treatment and changed the oil daily. I dont see the black smoke rolling any longer and the diesel fuel in oil does not seem as bad.

I did not block the fan from first 2 cylinders that's a great point.

As far as I know she is running optimally for the condition. I was concerned with lack of oil pressure, grenaded cylinder, and freezing to death / frozen water pipes. we have -10 windchill this morning. The worst cold in MS in probably 50 years. Last major snow cold winter storm here was in 1994 and this is worse.

On the bright side what an adventure and im loving the genset she is a beast.

 

[Digger556]

I live in Colorado around 1 mile ASL and run both 802a and 803a generators. I start to notice light black smoke around 80% loading. Given that I only have 84% of sea level oxygen up here and MS is <500 ft, I would expect that you could pull a 100% load without serious black smoke. If you are experiencing "plenty of coal rolling smoke", then the unit could be overloaded in those instances or something is wrong with metering pump balance, injector function or similar. Fuel in oil could be an overfueled cylinder, leaking injector or leaking metering pump.

Does anyone have an exploded view of the metering pumps? This was the best picture I had, but it doesn't show how the IP seals the fuel chamber from the crankcase.

 

[parttime]

Are the metering pumps able to be rebuilt? I have read that they are not but from real world experience is different than a Google search.

Currently its humming along. Early in the adventure there was coal rolling smoke with minimal load so im thinking it worked out the issue with injector stuck.

If you are actively running an 803a what is your oil pressure with fresh oil? After coming up to temp what does it sit at? With a fresh change cold oil its sitting at 45 psi per original gauge. After a 12-24 hour run its closer to 18-20 PSI. I think I do still have a diesel dilution issue on the oil but not near what I started with. Im trying hard to keep the load at least 50-60% but with well pumps, refrigeration compressors, and space heaters its hard to know whats kicking on and off at any given notice. This is the first attempt at long term run without grud power.

I have zero complaints so far. We are blessed with what our conditions are.

 

[Ray70]

People quite often disassemble metering pumps to clean stuck ones, but I don't know what happens if one is leaking, if it can be fixed or if it has to be replaced.
The oil gage on these machines are not all that accurate, but 45+ at cold start is normal ( there is a pressure relief valve in the oil pump to prevent excess pressure from floating the lifters when cold ) once warmed up, ~20-25 is not uncommon, especially if you are running 5W-40 synthetic or thinner in your climate. Adding a Tee and a good mechanical gage would not be a bad idea.
I believe your oil pressure switch will shut the machine down at either 15 or 18 PSI, so as long as it stays running you aren't that bad off.
If you were rolling coal at minimal load in the beginning, something was definitely wrong. As Digger mentioned, a little light smoke at ~80% load is about normal. Moderate Black smoke at under 120% is what I would consider abnormal.
It is not uncommon for a little bit of a workout to free up a stuck injector, stuck rings etc., so perhaps you are in a better place now?
If you haven't done so already, I would throw a qt. of ATF in the next tank of fuel for some added cleaners.

 

[Guyfang]

All of these posts are relevant. The reason I told you to reset the IP, is to level the playing field. That way all things are as they should be. The first IP is not in the same position as the rest. Then you can start with the next step. One step at a time and one less thing to think about. Like Ray, I think your IP is leaking and or stuck open. If you could get a known working IP, then you could change it out in a very short time and try it to see what happens.

 

[parttime]

UPDATE FROM TODAY: we are still humming along. I believe I have everything prioritized and running at this time. The inrush from the well with the hot water heater on is more than it can handle. After the pump is running there is no problem. I am going to add a soft start to the well.

I dumped the oil again after 24 hours. Still about 1-2 quarts higher than expected. So I still have some diesel diluting the crankcase. No black smoke rolling, not elevated temps, oil pressure sits around 20 PSI after getting to temp until it becomes so diluted then start slowly drifting south. I do see a light blueis tint smoke likely due to the dilution of the oil. Everything seems stable at the moment.

Any good recommendations for a soft start for well pump?

I have not made any changes to metering pumps. I do plan to pull injectors and metering pumps after this event has concluded and we get power back. I would hate to have to continue changing oil daily.

Whats the consensus on corrective actions? Should I rotate cylinder 1 metering pump to the right to lean out the mixture? How would I know whether its better or worse on the correction? While on and running or does everything need to be off? Remove replace all injectors and metering pumps? Remove, inspect, test, reinstall? What else is the likely culprit for diesel diluted oil?

Once again, we are blessed and very thankful for you all.

 

[Ray70]

Start by rotating that metering pump counterclockwise until the inlet hose is just touching the pushrod tube.
You may need to loosen the injector line to allow it to rotate ( if it has a ways to go ) if it's close already you might be able to just loosen the hold down nut and turn by hand.
You may not be able to tell if things improve, but it needs to be done. The pumps all need to be in the same position..... fixing it will not make anything worse!

I don't think your issue is injectors as the machine would not be running good if you had an injector issue, but you could pull them all out and have them tested to be sure. You could also pull off the exhaust manifold and look at the ports in the head.
If an injector is stuck open I'd expect that cylinder's exhaust port in the head to look abnormally wet compared to the others.
I'm betting you have a metering pump leaking into the crankcase. How to determine which one is the big question!
I'll need to think on that a while....
Also going to try to locate that other thread where the machine was leaking fuel into the oil.

 

[87cr250r]

Single phase or 3 phase? A VFD is superior to a soft starter for generator applications. The VFD allows the motor to start with zero additional inrush.

 

[BeStihl]

I would try to pull off the 1/4” fuel supply line from the suspected injection pump and plug it with a bolt in the rubber line and put a clamp on that hose. Run it for a while and see if the dilution stops, just an idea to slow the diesel maybe. If no change replace that line and try the next one in line, just an idea.
Daniel

 

[2Pbfeet]

@parttime How deep is the well? I also like VFDs for use as well pump "soft start" devices, but really deep wells may have some issues.

All the best, 2PbFeet

 

[Digger556]

Are the metering pumps able to be rebuilt? I have read that they are not but from real world experience is different than a Google search.

Currently its humming along. Early in the adventure there was coal rolling smoke with minimal load so im thinking it worked out the issue with injector stuck.

If you are actively running an 803a what is your oil pressure with fresh oil? After coming up to temp what does it sit at? With a fresh change cold oil its sitting at 45 psi per original gauge. After a 12-24 hour run its closer to 18-20 PSI. I think I do still have a diesel dilution issue on the oil but not near what I started with. Im trying hard to keep the load at least 50-60% but with well pumps, refrigeration compressors, and space heaters its hard to know whats kicking on and off at any given notice. This is the first attempt at long term run without grud power.

I have zero complaints so far. We are blessed with what our conditions are.

They hold 40-45 psi when hot., 45-50 psi cold/new oil. 18-20 psi is low, but not fatal to the engine. I would install a mechanical gauge to verify pressure.

I had some minor issues early on when I first got my units running. Once in a while, an injector or IP would get stuck and stop firing, causing the governor to open the others more and resulted in some smoking. Whatever got stuck cleared itself after 5-10 minutes, and regular load testing has kept everything happy.

Glad your unit is working when you need it. You guys got hit pretty hard.

 

[87cr250r]

I would not recommend removing the fuel supply line from an injection pump on the engine. This will quickly cause a failure of the pump and potentially result in damage to the camshaft depending what part of the stroke the pump seizes in

 

[jamawieb]

Hey Parttime, Im right above you in West Tennessee. I would be leaning towards an open leaking injector. In the post where you took your temperature readings, 150 degrees on the exhaust is cold, at operating temperature it should be around the 250 or above. The front cylinder will be colder but not that cold. In my experience, when the metering pumps fail you have the crankcase full within a couple of hours. When injectors are stuck open it takes several hours of running to fill the crankcase. After your power is restored, I would pull the injectors. I bet your number 1 injector (closet to the radiator) is going to be saturated on the tip. You can take the pumps out but you will need them hooked to the lift pump and usually have to push the metering spring on the bottom to see any fuel leaking. It usually gets worse over time too especially continuously running. The metering pumps have very close tolerances and if fuel is getting by the plunger to leak into the crankcase it just keeps eating away making the leak worse.

 

[BeStihl]

I would not recommend removing the fuel supply line from an injection pump on the engine. This will quickly cause a failure of the pump and potentially result in damage to the camshaft depending what part of the stroke the pump seizes in

Thanks for that reasoning, I didn’t think that one through. The thought of 1/2 gallon of diesel in the crankcase had me pondering of a way to slow it.