Cummins 6BTA Engine Problems

[Dougfuller]

I have a Cummins Marine 6BTA 370 HP Turbo that is in a 1997 Albin 32+2. The engine has approximately 1300 hours on it.

We recently took this boat to the Bahamas. In the process, we put about 135 hours on it.
The boat used 8 quarts of oil during this trip. There was a lot of “smoke” buildup on the transom of the boat. The turbocharger was rebuilt last year, so my mechanic thought it was best to do a compression test. Here is what he found:

Cylinder #1 285 PSI
Cylinder #2 361.5 PSI
Cylinder #3 348 PSI
Cylinder #4 270.5 PSI
Cylinder #5 345 PSI
Cylinder #6 345.5 PSI

Based on this test, my mechanic, which worked for Cummins for 10 years, feels this engine needs to be overhauled, which means removing the engine and installing a rebuilt long block. I am asking others on this fourm if you agree with this diagnosis, or is their something else we need to do before making the decision whether to replace the engine?
Thanks in advance

[never monday]

Originally Posted by Dougfuller

Based on this test, my mechanic, which worked for Cummins for 10 years

I question your mechanics basis.
My experience with Cummins is they do not publish a compression number. To use in determining the health of an engine. Instead they use a blow by test.

Now, I agree with your mechanic on the values of the compression against what you would see as normal. And in the same instance I to would recommend a rebuild.

[djmarchand]

Doug:

You posted the same question over on boatdiesel. Listen to Tony Athans. He can be a bit grumpy at times, particularly if you don't pay any attention to what he says. But he knows the Cummins B engine better than anyone.

Something caused your engine to wear out and consume a lot of oil. Rebuilding with a long block may not fix it.

David

[Chief Engineer]

The compression numbers all look kind of low to me.

1300 hrs is not a lot in my opinion

I am going to call my Cummins Guy and get his opinion.