Raw water temperature

[richardh10]

When I had our new volvo D2-40 installed the temperature of the raw water was 90° which seemed high to me, so I checked with the installer and he said it was OK. It has since run for a number of years without problems but recently the temperature is much lower. Today it has been running at 50°. Is this a problem? Heat exchanger?

 

[LittleSister]

Cooler sea water, and/or heat exchanger furred up and needs descaling (i.e. seawater unable to cool the freshwater coolant as well)?

 

[MikeBz]

Thermostat stuck open?

 

[Refueler]

First ... is the engine fully raw water cooled or Heat Exchanger cooled ?

If the engine is fully raw water cooled - then the temperature must be substantially lower to avoid clogging up the water channels ..

If the engine is Heat Exchanger cooled - then I would be looking at Thermostat and probably De-Scaling the system ...

Interesting though would be to know the engine actual coolant temp ??

 

[Channel Sailor]

Based on my experience of small 14–18hp both raw and coolant and yanmars: Where where/are you measuring 90 degrees C e.g. At the outlet to the sea or before the muffler. I would say 45 degrees at the seawater/exhaust outlet skin fitting, warm/hot to your hand. If it was 90 degrees C then you would see evidence of steam (if in cooler weather) and a skin burn to your hand, so be careful.