Volvo d1-20F seawater in coolant

[ben373]

Hello

I now have a Volvo D1-20F 400hrs and 3 years old

Oil looks good

The coolant header tank is slowly filling up with seawater.

Flow from the exhaust is strong and the engine performs very nicely.

Obviously a problem. I cannot see any leaks etc. Where should I start to look?

Thanks in advance..

[DougR]

You could have a pinhole leak in the heat exchanger element, allowing sea water to leak into the coolant. Also a possible O ring leak at the rear heat exchanger element cap allowing a leak from the seawater side into the coolant, although I would think this would also leak to the outside.

DougR

[Lepke]

The heat exchanger is the only place sea water and coolant are in close proximity. It can probably be repaired. If you don't have a shop specializing in heat exchangers, a radiator shop should be able to fix.

There are many sources on line for replacement heat exchangers. All cheaper than Volvo. Also used ones may be found on ebay.
Volvo Heat Exchanger
https://lencocoolers.com/
http://www.seakamp.com/
Custom & Stock Marine Heat Exchangers & Cooling Systems - Orca, WA