MEP-803A has zero compression and lots of soot

[diogenescreosote]

I bought an MEP-803A a year ago with 400 hours, and it now has 900 hours. It was working fine, as far as I could tell, and then one day it would not start, and it hasn't started since.

When I try to start it, there is no rumbling, the starter motor sounds like it's spinning free. A mechanic opened up the top of the engine and showed me an immense amount of hard carbon buildup where the exhaust leaves each cylinder. He said he suspects the rings are stuck open with soot, and that it will work if the head is removed and the whole engine is cleaned out.

In the 500 hours I've used the machine, I've run it at about 3.5 kW. I know diesel engines like more load than that, but I didn't think it would be so low as to cause this much buildup.

I have two questions:

1. Was my running it at 3.5 kW the cause of this problem?
2. Is cleaning everything likely to make it work?

 

[jcollings]

Check out Daybreak Angus
Videos,
You have to run those 80 threes hard after running them so light to clean up otherwise you get the wet stacking

Sent from my SM-G975U using Tapatalk

 

[Ray70]

Sounds like you have carboned up the exhaust and the valves are hanging open.
I have purchased several sets in that condition and found the easiest way to repair is to remove the rocker arm covers , rockers and injectors.
Fabricate and adapter so you can put air pressure into the cylinder through the injector hole.
Apply air pressure and then remove 1 valve spring and keeper, then attach a cordless drill to the valve stem and spin the valve a little. the sound of the air escaping from the leaking valves will quickly change as each valve seat is scraped clean.
repeat this on all 8 valves and reassemble.
NOTE: putting the piston at TDC will prevent any accidental dropped valve into the cylinder, but it will be difficult to keep at TDC when applying air pressure, but the air will also keep the valve from dropping.

Once it's running again, do a good long load test and burn out any carbon left in the exhaust system.

The other option is to pull the head and remove / clean and lap the valves.

 

[Daybreak]

Howdy,
I had a unit which was wet stacked. I removed the muffler, then used a shop vac to suck the ports as best as possible. I then removed the exhaust manifold. I scrapped and pressure washed it clean. I also washed out the muffler. Purple power and shaking it. Washed it out the best I could. Put everything back together, and ran it hard. Started around 70% load, and kept increasing the load over a 5 hour period. The engine sounded a lot better by the time I was done. Of course, you look around and notice all the black carbon specs everywhere. Obviously it helped to clean out the muffler too.

 

[DieselAddict]

Its unfortunate but the direct answer is - yes - running a 10kw machine with ~3kw of load causes this problem.

As already stated above you need to get the valves freed up so you have compression then run it with increasing loads until its working as it should. Cross our fingers the rings are coked up and you don't have to tear it completely down.

I received a generator a few years ago that was heavily wetstacked. It would barely carry any load and it smoked badly. It took a few hours of progressively increasing the load to get everything burned out and operating well again. Filled my yard with smoke and sparks from the gunk in the exhaust burning off. This one luckily recovered well and is still working today.

Once you get it going you'll need to find a way to load bank it at more than 80% load or this will happen again.

Have you considered going with a smaller generator? Sounds like your energy needs may be a better fit for a MEP802.

 

[jcollings]

Hey,
Diesel Addict,

On a mep 803a what would be the minimum load % to not have a issue like we see here?
I have run mine around 25 to 30% for storms, but always bank up to 100 and bursts to 115% afterwards

Thank you

Sent from my SM-G975U using Tapatalk

 

[Light in the Dark]

To the original poster... I honestly think you should acquire an 802, and sell off the 803 (acquire first, sell second... so you arent without). The 803 is just not a good fit for your needs.

I think 40% is the absolute minimum you want to run, and even then... you are going to need to get it hot and loaded often.

 

[jcollings]

My apologies to the original poster for commenting on a members comment. It was out of line.
Not trying to step on your original question.
Carry on, Have a great day

Sent from my SM-G975U using Tapatalk

 

[Light in the Dark]

My apologies to the original poster for commenting on a members comment. It was out of line.
Not trying to step on your original question.
Carry on, Have a great day

Sent from my SM-G975U using Tapatalk

I dont personally think its out of line. Its not like you were trying to sell us some Amsoil or used tupperware with the post

 

[DieselAddict]

Hey,
Diesel Addict,

On a mep 803a what would be the minimum load % to not have a issue like we see here?
I have run mine around 25 to 30% for storms, but always bank up to 100 and bursts to 115% afterwards

Thank you

Sent from my SM-G975U using Tapatalk

There isn't a hard and straight answer I can offer. Based on my personal experience if the load is at least 60-70% for the majority of the run time then its not a problem. If you are running 25-30% most of the time then as you are already doing you need to get it up above 80% long enough to clear everything out. The higher you go over the 80% the less time it will take.

Instead of going for a fixed time I go by how well the unit is handling load in combination with what the exhaust looks like. If its sluggish picking up load and there is more than the normal exhaust haze I run it until the exhaust clears up and its able to handle load transitions normally. Once it seems to be running well I go for 30 more minutes at between 80-100%. Give it a 5 or so minute cool-down then put it to bed.

 

[DieselAddict]

My apologies to the original poster for commenting on a members comment. It was out of line.
Not trying to step on your original question.
Carry on, Have a great day

Sent from my SM-G975U using Tapatalk

I don't think it was out of line in this case since the information IS relevant to their situation.

 

[Guyfang]

The Army says 70-80%.

 

[Light in the Dark]

I have no doubts that for truly sustained running (in service) that 70%+ would be where you want to be. I had to use my 802 the other day to run an electric stapler (.7A) for a few minutes.... felt kind of silly, but I couldn't get power out where I needed to do the work... so picking up the genset with the tractor and bringing it to where I needed it was easier!

 

[dav5]

I have no doubts that for truly sustained running (in service) that 70%+ would be where you want to be. I had to use my 802 the other day to run an electric stapler (.7A) for a few minutes.... felt kind of silly, but I couldn't get power out where I needed to do the work... so picking up the genset with the tractor and bringing it to where I needed it was easier!

I have a loader tractor I can use to move my MEP'S if I have to but really they just aren't portable. The MEP831A requires a 6 man lift in the armed forces believe it or not although in a panic 2 men could move it. Lack of portability is the reason I will never get rid of my Honda EU2000

 

[Light in the Dark]

I had a Honda 5kw industrial unit for years, but it became problematic and I moved it out. Been considering swapping out of the head on a 501A I have to a 240V unit (already own it). Not enough hours in the day.

 

[tiger]

Newby here. A soiled senior citizen, 20 year navy vet. Has anyone tried water injection to solve this issue? I used it on a 73 504 peugot and later an 85 505 2 gallon garden sprayer while under heavy load cleared them up. I did the 73 once sold it at 153000 miles, the 85 twice, sold at 85000 miles. now have a 803a off craigslist so far so good.