Oil over fill

[Ron Langdon]

After my last service (40,000), I noticed blue smoke from the exhaust. Before leaving the provider's area, I talked to the mechanics about it. One fellow noticed the oil level on the stick was too high, indicating over fill. They drained 2 quarters ( 35 had been added [requires 34]. I've driven less than 50 miles since the oil change and am again getting blue smoke at start up and in fast idle. Events only occur at start up or with increased rpm, eg fast idle. Stick still indicates a little over operating level. Im taking the coach back to provider, but am wondering what if any serious consequences I might expect from over fill.
Thanks,

Ron Langdon
C9
2006 Beaver Monterey, Laguna IV

[Roger Bowton]

You should be ok once the level is correct, but drive no more than you have to to get it right. Overfill can cause foaming.

[Gerald Farris]

The main problem with an overfilled crankcase is that the crankshaft can hit the oil in the bottom of the oil pan and whip air into the oil (foaming) so that the oil pump is picking up air with the oil to lubricate the engine. Since we all know that air is not the lubricant that is needed in a Cat engine, it can cause damage. However, one or two quarts of excess oil should not cause a problem in a 34 quart system, but a lot more than that can cause a problem with severe overfill resulting in engine vibration from the crankshaft hitting the oil and engine failure.

The bottom line is calibrate your dipstick so that you know where full really is and never overfill your crankcase. It is also a good idea to wait until the engine is at the add mark on the dipstick (one gallon low) before adding oil if it is ever necessary as per Cat's recommendation.

Gerald

[Ron Langdon]

Thanks for your advice. Coach goes in Tuesday am. We will be leaving on our leisurely migration south in about 2 weeks. Already getting eager for the trip. Thanks again!
Ron
C9
2006 Monterey Laguna IV

[Keith Moffett]

The first time I changed the oil in our 3126 CAT, I miscounted and added 2 extra.  I realized this right away but didnt realize the harm.  After all what's 5 or 7 % over in a large crank case... right?
I asked several diesel mechanics and they all said no problem, let it go.  I changed the oil again in advance of our trip to Redmond, this time with the correct ammount.
Seems to me that after 4 or 5  truck mechanics all said the same thing, one would get it right.  Only now do I get the correct answer and sound reasons of that answer.  Makes me wonder what other information I have gotten in similar places that was just as worthless or damaging.
Moral to the story:
Ask the mechanic and then verity the information here on the forum.
Thanks everyone!
Keith

[Gerald Farris]

Keith,
The truck mechanics that you talked to were right if you meant 2 quarts. Like I stated in the previous post 2 quarts should not cause a problem in a 7 1/2 to 8 gallon system, but if you meant 2 gallons, they were very wrong.

Gerald