Outboard winterisation

[pumpsmynads]

Hi, done a quick search and can’t see this specific question(s) being asked previously...

I have my boat on a pontoon and use it all year round (Poole harbour.) I have a mercury 115ct outboard and the manual says I should leave the outboard down (in the water) when the temperature is close to freezing so as to prevent water freezing in the leg. I tilt it up presently when leaving the boat.

Does everyone else do this?
I assume with low temperatures marine growth is low over winter so leaving it down for perhaps a week between uses ought not to be an issue?

The manual also says I should flush with freshwater after every trip - I have never done this!! Oops. Could I add some antifreeze here?

many thanks in adv. Happy new year all.

 

[Hot Property]

I leave my boat in the water all year and when the forecast is for freezing weather I pop down and lower the engine into the water. Fouling is non-existant at that time of year.

You should have been flushing the engine however - there will be a flushing port to which you attach a hozelok type of adaptor then hosepipe. 10 mins flushing (even 2 mins if time pressure) will be hugely beneficial and keep corrosion at a minimum. Your maintenance manual will have details on what to do.....

 

[pumpsmynads]

Thanks HP. That’s exactly what I was thinking of doing.

I will be adding the flushing to my routine. I hose down the boat after every trip already - I just didn’t know about the flushing requirement.

 

[Beamishken]

I wonder if you need to trim the engine up to allow the powerhead to drain after flushing. I know outboards drain the powerhead when out of the water but do they drain while stationary and trimmed down in the water? Not something I've thought about before but could be an issue for the op if fresh water is trapped in the powerhead during cold spells