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Dulcesuenos · 12-06-2015, 14:28

So we installed a new 8 gallon waterheater runs off 110 and engine driven, just noticed the engine seems much hotter, (133 degrees to be exact on any cooling system parts and 110 ish everywhere else), while back on the dock and with the power on. Is the engine staying at that temp for weeks or months at a time a big issue? The eng is a yanmar 2gm20.
Any concerns? if so How to correct?

**sailorchic34** · 12-06-2015, 15:03

Quote:

Originally Posted by Dulcesuenos

So we installed a new 8 gallon waterheater runs off 110 and engine driven, just noticed the engine seems much hotter, (133 degrees to be exact on any cooling system parts and 110 ish everywhere else), while back on the dock and with the power on. Is the engine staying at that temp for weeks or months at a time a big issue? The eng is a yanmar 2gm20.
Any concerns? if so How to correct?

Ah you have a thromosiphon. That is the hot water is flowing from the water heater, which may be installed below the engine connections. That is allowing hot water to circulate by convection. It will not hurt the engine, but your burning more electric to do that.

To stop that, put a 16" long U bend (pointed down is best, but up works too) on the upper engine water connection on the water heater. That will stop the circulation in the engine loop.

Sailmonkey · 12-06-2015, 16:55

It costs you cash, but being hot all the time is wonderful for the engine....it prevents condensation inside the engine.....sitting hot you can avoid most of the problems associated with pleasure craft engines, those caused by lack of use.

Sent from my iPhone using Cruisers Sailing Forum

DeepFrz · 12-06-2015, 16:56

Wonderful in colder climes.

adamsteel · 13-06-2015, 20:04

Hello Sailorchic 34. Do you mean Thermo syphon or is it Thromosiphon, where hot/warm fluids rise and cool fluids fall, is the bent pipe an anti syphon item. Regards Les , adamsteel.

**sailorchic34** · 23-06-2015, 16:44

Quote:

Originally Posted by adamsteel

Hello Sailorchic 34. Do you mean Thermo syphon or is it Thromosiphon, where hot/warm fluids rise and cool fluids fall, is the bent pipe an anti syphon item. Regards Les , adamsteel.

Ah Thermo-syphon, darn fingers can't spell. Putting a U bend in a hot water riser (pipe or hose) acts as a heat trap and stops the heat from rising. It's a very standard way of dealing with that issue on the land side. Least wise in the USA. Very common problem on land. Less so on boats.