fuel in exhaust?

[MIspecial]

I have just an hour on my 12/2 mostly with not load or low rpms.  I am getting very black fuel? coming out of the exhaust.  Is this because the engine is getting too much fuel or because the engine is not being run long enough to get hot and burn all the fuel?
I am still new to this and any help would be great.

[sawmiller]

Hi MIspecial

That what they call slobbering not enought load and not getting hot enough. It will  usualy go away with a good load and getting up to temp.

Regards
Tim

[MIspecial]

Still getting quite a bit of black liquid leaking from the exhaust.  I now have my gen head working and I powered my garage most of the afternoon.  Now te engine is quite a mess.  There are puddles of this black stuff all over the lister, floor and gen head.  Any ideas?

[JohnF13]

On new engines it takes quite a while for the rings to "seat", especially if you have run it for a bit on little or no load.  Put a big load on it and let it run and get up to a good temperature (190F exhaust water), the rings will eventually seat themselves and everything will be fine.  It can take upwards of 100 hours (or never on lightly used engines) so have patience!

[JohnF13]

Also, forgot to mention - have you balanced the cylinders - are both running at about  the same temperature? 

[diesel guy]

If a new diesel engine is ran at low speeds and little or no load, the cylinder will begin to glaze and wet stack. When this happens, you have to pull the heads and cylinders. Then re-hone the cylinders and emery cloth the rings (or replace them), then reassemble.

The piston rings seal proportionally to cylinder pressure, the higher the cylinder pressure the greater the expanding force of rings to the cylinder walls. Therefore, under high cylinder pressure the rings offer the highest sealing capability.

John is correct, run a heavy load. Heavy surges would not be good for a new engine. In your case I would run 4 - 1,500 watt heaters, 2 per hot 120 lead. This would place a constant load of 4,500 - 6,000 watts to the generator and proper loading to seat the rings.

I would run it 24 hours a day until the rings seat, this will accelerate the break in. By operating at full temperature under load and not starting and stopping the engine, to allow it to cool. This promotes cylinder glazing.

Good luck and I hope this helps.
Diesel Guy

[dkwflight]

Hi I second the motion. Load it up and run it hard.
I wouldn't leave it unattended tho. To much can happen.
Take a look at the rack at the injecter pump. Make sure that you can load the engine up to the point where the rack is all the way to full fuel and drop some of the load.
You will see a lot of black smoke, don't worry about the smoke. As the engiine wears in the smoke will let up.

I am at about 66 hours and I believe the engine will need more running to fully break in.

I would recomend running for a couple of hours and shutdown and cool off. Check the oil, pull the sump plate. I felt around in the sump with my fingers feeling for any grit. Sand is not magnetic!. I had a toilet paper filter and I would suck out the oil and force it back into the sump through the filter. You can do nearly the same thing by draining the oil and pour it through several layers of paper towel.

The screen  for the oil pump pick up was covered with something like lint.

My pump needed the check balls replaced and I lapped the seats with one of the new balls. I bought the balls at a bearing place. mine were 1/2"
Good Luck
Dennis

[MIspecial]

Thanks guys!  This weekend I plan to let her run a while with a load.  We'll see what happens.
Matt

[buickanddeere]

  The coolant has to be at least 195F before the engine will cleanup. The engine was designed to run continous at 80% of max load. Injectors spray better at higher rpms and at higher delivery amounts.