Calorifier not heating water

[carmel118]

Hi. We have a Seamaster 27 and just installed a replacement Perkins 4108 as the big end went on the old one. There is a new impeller in the pump and now the engine seems to be running a lot cooler with more water coming from the exhaust, consequently, we don't seem to now be running hot enough to trigger the thermostat to let water into the calorifier. It is the old thermostat which we reused as it is still working fine. I have read quite a few different forums on this kind of thing and I'm slightly concerned that our engine won't be happy running cool as I read that diesels like to run hot? But the main reason for the post is that we are not getting any hot water! Sorry if this is a stupid question, presumably the current thermostat triggers at around 80 degrees, should I buy one that triggers at a lower temperature, or does anyone know of a solution to our problem? Thanks Carmel

 

[nigelmercier]

Could be an airlock in the feed pipes.

 

[PCUK]

The calorifier feed should come from the engine side of the thermostat. This means it gets hot as quickly as the engine and before the thermostat opens. If the engine is running cool then it sounds as if the thermostat is stuck open.

 

[rafiki_]

Firstly, welcome to the forum. Sea masters are nice boats. Where do you do your boating?

You say the engine is running cooler, but can you give us some numbers? The calorifier should be heating whatever the thermostat is doing, so it sounds like a blockage somewhere.

 

[carmel118]

Hi Rafiki, nice to meet you! We usually poodle around in the Cookham area. We are planning to take some measurements tomorrow and have another thorough check for air locks, I'll come back to you, thanks everyone!