MEP003 smokes/misses

[Harleyd315]

I have an 003 that I have gone over and got running. It starts up and smokes a bit till it warms up then clears up as the engine gets warm no load. I let the motor warm up and load tested the set, 4 mins at 75% load I heard a small pop and saw smoke coming out of the area of #2 injector. I pulled the injector saw some exhaust residue on the side of the injector and ordered and replaced the injector seal. The motor again fired up ran with a little smoke but cleared up after warm up. Put a load back on the set and after about 5 mins I got smoke out of the front exhaust pipe again. The engine almost sounds like it may have a small miss. Shut it down, let it cool off pulled the valve covers off and checked all the valve clearances. All were a little on the loose side so I snugged them up and fired the unit up again but no differance with a load on it, it still smokes. I looked at the desert tan paint on the exhaust pipes and the front one is a different shade than the rear pipe. I took my infared thermometer and found #2 cylinder to be about 150 Degs F hotter than the other cylinders. The smoke is a whiteish color not black. I was wundering if anybody has any similiar problems with thier sets? What should I be looking at the injector or the IP pump? Can something stick in the pump on just one cylinder or should I try an injector first? Also some members have talked about copper gaskets for injector mounting, the one I removed was a metal/fiber type material similar to the exhaust manifold gaskets I have replaced on some heavy equipment. Which is correct, copper or the metal fiber for where the injectors seal against the head. Thanks for the help.

 

[Keith_J]

Injector. It is probably opening later, causing heat to be wasted through exhaust instead of being turned into mechanical work. This also causes the injector to overheat.

Have a professional service the injectors.

 

[storeman]

There are two seals per injector. When you remove the injector from the ribbed aluminum heat sink, you will find a copper ring on the injector body or in the base (hole) in the heat sink. this is easily smoothed with wet sand paper. The other gasket is the one at the bottom of the big hole the heat sink goes into. Most of the discussion you have seen regarding copper gaskets relates to the one on each glow plug. I need several of them but don't know specs or where to find them.
Several others have the same problem
Jerry

 

[Isaac-1]

Try asking over on the Smokstak board in the Onan section, someone there will likely know the specs or a source for these, just tell them what it is for since the MEP-002 uses a militarized version of the onan DJE engine, they should be the same as the rest of the Onan Diesel J series.

Ike

 

[patracy]

There are two seals per injector. When you remove the injector from the ribbed aluminum heat sink, you will find a copper ring on the injector body or in the base (hole) in the heat sink. this is easily smoothed with wet sand paper. The other gasket is the one at the bottom of the big hole the heat sink goes into. Most of the discussion you have seen regarding copper gaskets relates to the one on each glow plug. I need several of them but don't know specs or where to find them.
Several others have the same problem
Jerry

I'm trying to get my civy Onan genset going. It's mechanically the same as the MEP003. It has the same injector design. I put mine back in and found the gaskets were leaking that look like exhaust manifold gaskets. Could I get away with some copper o-rings from the parts store in that section as well?

 

[storeman]

Patracy,
I don't know. Keith put up a link to a supplier of the copper gasket for the glow plugs.

I have made a practice of removing the injector body from the ribbed heat sink and wet sanding the sealing face of the aluminum heat sink, then doing the same thing to the metal-fiber gasket you are referring to. It seats on a metal disc about 3/16"m thick which I also pry out of the head and that disk in turn seats to the head on another very narrow perimeter copper gasket. I try to smooth them all on 400 oiled wet sand paper and have not noticed a sealing problem so far. I'm sure Keith has a better procedure than my field expedient approach.
Jerry

 

[patracy]

Yeah, it's not the glow plug copper gasket. Or the copper o-ring in the injectors. It's the "exhaust gasket" material seal that goes between the heat sink and "washer". I picked up some aluminum oil plug o-rings tonight as well as some copper ones. They appear to be the same ID as the washer so I'm hopeful they'll work in place of it. If not, I'm only out $3 for the set.