Bacteria in Cooling System


Keel cooled EMDs and reduction gears have been found to have bacteria in them that causes Pencool 3000 nitrate levels to drop quickly. Coolant has been analyzed by Penray Corp. We are unable to flush the system and would like to use an additive. Bleach was recommended but that seems severe. I suggested vinegar but have not heard back from Penray yet.

Anybody seen this before? Any suggestions?

It’s not a silicate drop-out or “green goo” problem.

Generators use identical mixture and no problems were found in those systems.


I don’t see any problem with a bleach treatment. Most coolant treatments and bleach are bases. Vinegar is acidic and there would be some kind of reaction. Probably the “goo”.

The chlorene will evaporate. An easy source would be MSD effluent treatment tablets.

A system flush may still be required if there is too much drop-out from the shock treatment.



Thanks, second opinion relieves my concerns. We’re not scheduled for yard time 'till next summer.