Cooling water vented loop

[David Revill]

I have a 1981 Catalina 30 with a 5411 diesel engine that has a vented loop in the hose that connects the thermostat to the silencer. This vented loop needs either replacing or removing. Would I have problems with siphoning if I were to remove the vented loop and kept only a loop of hose that rose above the water line?Thanks in advance for any advice.

 

[Todd Osborne]

You need a vent in the loop...

to break any suction that could start a siphon. Until you do that, ALWAYS close your through hull immediately after shutting down the engine (or it may fill up with sea water).