mep802a oil gusher

[builmord]

everything looked fine. gen ran and held a 100% load for 2 hours. so I changed the oil, used 5w40 as if is cold here in virginia. ran the engine with new oil and decided to check for blow by by removing the oil dipstick. mist and oil spray came out of the tube. I had done this check before with the old oil and all was fine. could the thinner oil caused this ? also the TM's say there are two different marks on the dipstick, one to check oil level with engine off and one to check with engine running. I didn't see any double markings. could an oil overfill be causing this new blow by ?

 

[Zed254]

I use 15W-40 and had the same symptoms with my 802. I believe it's got a little cylinder glaze from low demand running so I put around 100 hours of high demand run time on it. Still had some sloshing of the oil when I looked at it so I bought a manometer and confirmed good vacuum in my oil reservoir. You may want to do the same. The peanut butter jar acts as a pressure dampener: when I checked vacuum without it the variable pressure in the oil reservoir caused the fluid in the manometer to disappear ..... out of the tube with pressure and into the oil pan with vacuum. The peanut butter jar has enough air volume to smooth the pressure spikes out very nicely.

Check LUBRICATION ORDER ARMY LO 9-6115-641-12 for the machine: it does not call for 5W oil so this may be part of the problem. Oil over fill is not a good thing.

 

[Guyfang]

The milatary spent millions of dollars for producing TM's. Look at the LO. Use that type oil, specified for the gen set and temperature.

Do do check the engine crank case vaccine. Read the TM, and it tellers you how to make a cheap, easy water manometer.

 

[builmord]

looks like I cause rather than fix problems. a slight over fill and 5w40 verses 15w40 caused blow by. I changed the oll back to 15w40 and was careful not to overfill it and presto blow by by issue solved. thanks all for the help. SPOKE TO SOON. Sadly the blow by is still there. ran the unit today and oil mist and splash comes out of dipstick hole. funny that the unit runs so well, starts easy and doesn't smoke but blow by exists. aren't worn rings the cause of blow by ? I would think that burning oil and smoke would also be present in a unit that has blow by. Is there a crankcase vent somewhere that could be clogged? sadly I think a ring job is in order

 

[Chainbreaker]

Your now very clean crankcase thanks you!