Now that the dust has settled and I have taken a closer look at the recently purchased Cat D311 genset, I have made a few observations. I realize that there may be multiple causes.

1) Engine starts easily.

2) Intermittant miss about every 100 revolutions (no load at operating rpm).
Breaking each injector line results in about the same rpm loss with no
change to the intermittant miss.


3) Slobbering (more accurately drooling) a thick viscous oil/tar. Not little
droplets being sprayed out in the exhaust like I normally associate with
slobbering.

4) No other obvious symptoms such as oil in water, water in oil or bubbling.

The slobbering/drooling I can understand. The intermittant miss confuses
me. I plan to pull the head to see what's in those 4 holes but could use a little guidance about possible causes to some of these symptoms.

Thanks in advance for any suggestions,
tom

Slobbering normally is caused by an engine running without a load or partial load on it. If you could some how get a load as much as possible on it then keep it on for a couple hours or more steady but with a Gen. set in kind of hard. What happens without a load the rings cause a glazing of the cyl. liners & this causes the slobbering as oil gets by the rings and out the exhaust stack. With older engines before the cam ground pistons & improved rings we used Bon-Ami dust and would loosen the intake exhaust manifold & let each cyl. one at a time suck a little dust in and then go on to another cyl. Cat said in later years with the later style pistons and rings not to use the Bon-Ami but if the problem came up just to use the heavy load running.I have did both procedures over the years at the dealer & always worked out pretty well unless the engine was worn out.You didn,t say which D311 you have but the old D311 used in the D2 tractors was a 5V5001 & up and the later one with the compact fuel system and the pump housing on the right side was a 51B-- D311H engine. I wouldn,t pull the head for now but go through the procedure I explained to do and see what happens. I would kind of think that the little miss you get is a build of the oil causing it till it burns a little up or pushes it out the exhaust stack.Your explaining that each cyl. seems ok as far as firing when you crack the fuel lines seems to tell me your cylinders are firing about normal but the oil is causing the miss. Let us know how it works out and if it does but don,t pull the head as the only as the last result as I,m pretty sure if you get a good steady load on it that would cure your problem.

Thanks SJ.
I know I need to locate a load center or something to load it down but I'm not in a position to put a load on it right now. It's kinda the chicken or the egg. I'm hoping to kill the miss and slobbering before I haul it to where I need the power (a 5 hour haul one way and a real booger to unload).

I'm going to look and see if I can find a way to burn some watts locally. You wouldn't think it would be that difficult to locate a portable watt eater but so far I've not had much luck.

Thanks,
tom

Tom I don,t know if your Cat dealer has a load bank to put a load on a Generator or if they have a Gen dept. but the dealer I worked for had a centralized one that they passed around to the other branches within the Co.so I,d try to see if your dealer has one as the problem will still be there later unless the job your taking it to will have load enough to be of any value for the problem.

I have a 34/15 genset that after I got it togather I got a old electic stove and turned on all the burner . That put a good load on it. I got the stove from the appliance store They where going to throw it away. Don't use your wifes stove ,I had this out side. If you need more load get two or more stoves.

Great idea Jeff. I also looked on epay and found some shop heaters rated for 220v / 5600w and although these are fairly cheap ($150) and compact, I probably wouldn't need them after messing with the genset. Not much use in south Texas for a high capacity heater but I might be able to find several of these at a rental to get me by.

When I First Got My # 12 Motor Grader It Hadn't Run For A Few Years... It Did The Same Thing And Then Gradually Quit After A Few Hours. And At About That Time I Found Out That These Engines Unlike Other Engines Need The Crankcase Oil Checked For The Proper Level, while Running. It Seemed Shortly After I Started Checking And Adding while Running the Problem Ceased. It Could Have Just Needed To Reseat The Oil Rings Too. I'm Guessing I Was Trying To Maintain To High Of An Oil Level.

As Far As Missing, Clogged Fuel Filters Or Anything Else Restricting Flow Of Fuel Could Be The Cause. I Have Found Ice From Condensation In The Tank Completely Clogging Lines
1 Keep Fuel Tank Full
2 Drain A Little Fuel From Bottom Drain Plug Before Running Engine
The Water And Residue Settles At Bottom Of Tank When Standing
3 Change Fuel Filters Bleed System And Make Sure It Isn't Leaking
4 Seafoam Never Hurts Anything And Anti Gel In Real Cold