Winterizing a 3.7L 4cyl Mercruiser Alpha I/Four Winns IO?

[syzygyus]

Winterizing a 3.7L 4cyl Mercruiser Alpha I/Four Winns IO?

I'll try to get this right... I have 1985 Four Winns, with 170HP 3.7L 4cyl Mercruiser IO.
Model 170MR (Alpha I) with antifreeze and a heat exchanger.
Last year all I did was drain the water from the heat exchanger, but when lowering prop/removing lower unit, some water came out (maybe a quart or less).

What else should I be doing to properly winterize? (Purging water with RV antifreeze shouldn't be needed on this one).

What additional steps should I be taking? Startup for a few seconds to purge water, or is that useless or damaging?
Would it be safe or stupid to startup the engine for X# seconds to exhaust minimal water in system/tubes, or leave it alone?

Thanks

 

[Bondo]

Re: Winterizing a 3.7L 4cyl Mercruiser Alpha I/Four Winns IO?

Winterizing a 3.7L 4cyl Mercruiser Alpha I/Four Winns IO?

I'll try to get this right... I have 1985 Four Winns, with 170HP 3.7L 4cyl Mercruiser IO.
Model 170MR (Alpha I) with antifreeze and a heat exchanger.
Last year all I did was drain the water from the heat exchanger, but when lowering prop/removing lower unit, some water came out (maybe a quart or less).

What else should I be doing to properly winterize? (Purging water with RV antifreeze shouldn't be needed on this one).

What additional steps should I be taking? Startup for a few seconds to purge water, or is that useless or damaging?
Would it be safe or stupid to startup the engine for X# seconds to exhaust minimal water in system/tubes, or leave it alone?

Thanks

Ayuh,... Welcome Aboard,.... It should be stored with the drive Down, or off the boat,...

Stupid,..... turnin' the motor over will Destroy the impeller,.... Don't do it,...

 

[Lou C]

Re: Winterizing a 3.7L 4cyl Mercruiser Alpha I/Four Winns IO?

On this engine, is the exhaust manifold raw water cooled or part of the closed cooling system? Because if its raw water cooled you must drain it too.