At what precentage is fuel dilution to high?

[yucca]

I am having some fuel dilution issues on a few engines with my fleet.
One example:
Cat 3512 with 4700 hours current. 3400 hours on the oil.
86 gallon sump.
By-pass filtration.

The current sample has a 6.4% fuel dilution. Last sample was The current visc@100 degrees is 11.84. The previous was 12.93.

The TBN is 5.67. The previous was 8.0. At what point is the dilution % to high?

 

[bsigg]

anything over 2.0%

Are you getting that oil hot enough? 86 gallons would take along time get to hot.

 

[yucca]

Yes I only pull the samples when the engines have been running for a while and are warm.

 

[The motor guy]

3400 hrs on the oil? It could be a bad injector leaking fuel or it could be how the engine is operated, if you let it idle all the time this can happen. A loose injector line can also cause this. Usually they stay around .5 to 1.0 percent fuel dillution.

 

[yucca]

Yes 3400 hours. The oil has a particle count of 16/13.

It has brand new oil now. We are going to trend sample every 50-100 hours on the new oil.

 

[The motor guy]

Is this a tug boat engine? How is the engine operated most of the time? Is it running at a heavy load and high rpms to keep it running hot enough?

 

[yucca]

Originally Posted By: motor_oil_madman
Is this a tug boat engine? How is the engine operated most of the time? Is it running at a heavy load and high rpms to keep it running hot enough?


Pump motors. 30% load. I want to say 1100 rpm's. In the best case scenario one pump would run 24 hours then taken offline and then the other 3512 would run 24 hours.

 

[Skooba]

I'd say 1% Reportable, 5% Unacceptable, 10% Severe