Engine Zinc?

[Wandering_bill]

I've got the Volvo MD11C, raw water cooled in my 323.  Just wondering from other owners if there is a zinc in the raw water cooling system somewhere that I am missing?  I see no mention of it in the shop manual....

Thanks,
Bill

[Rusty Pelican]

no zinc

[Wandering_bill]

Interesting.  Is it because the system is all cast iron that there aren't any galvonic problems?

[Rusty Pelican]

Yes there are.  Your exhaust manifold will be the first to go.  There are petcocks on the engine block. Keep these clean and un cloged. Flush with fresh water as often as possible.  Flush the cooling system with fresh water for a least an hour before you add antifreeze .  Let the freshwater soak in engine for a few days.  Use regular antifreeze at full strength for winter layup.  I hate the fact that the MD11C is raw water cooled

[My Cyn]

The previous owner of My Cyn had a fitting installed that facilitates fresh water flushing of the engine cooling passages. I flush for about 10 minutes prior to shutting engine down.

Regards,

Bill