Atomic4 - water jacket side plate

A4-aholics might be interested in this.

no water out the exhaust
+ water intake thruhull is open
+ impeller is fine
+ thermostat seems ok
+ water in the bilge but I just pumped it dry and why is the alternator wet

= corrosion hole in the water jacket side plate.

replacable (by mechanic - I wouldn't try it on my own unless the engine was on a bench). Had ss bolts instead of original so this was at least the second replacement.

--Steve

That's my next A-4 project!

Hummmm_______

Salt water + no zincs (IMHO) = holes in water jackets and exhaust manifolds in raw water cooled engines !!
Calls for a close inspection of any part that is in contact with salt water.

A-4 Engines.....

Aren't known for having engine zincs unless they have raw water cooling.

*sigh*

I guess with raw water cooling there is water retained in the water jacket when the engine is shut off. Should this be run out when putting the boart away for awhile (say, a week) - that is, close the intake while the engine is running until exhaust is waterless?

. . . by the way, I also wonder if the fuel valve should be closed until engine starves.

An engine sitting in salt water.

Steven and all, I keep my boat in salt water here in SoCal and have devised an engine flush system, the core of it being a 3-way valve that shuts off the raw water and takes from my onboard fresh water. After every use of the engine, I can with the flick of a handle, flush the engine (in my case, the heat exchanger) of all salt water. It only takes 20 seconds and three quarts of water with the engine at idle. So whenever the boat is at rest, in the slip or on a mooring at Catalina Island, the engine is sitting in fresh water. I keep the engine key near that 3-way valve under the galley which forces me to check to see if it was remanifolded back to raw water before the next use. Regards, Glyn Judson, #E31 hull #55, Marina del Rey, CA

Curious to know if you are having any less corrosion with the fresh water flushing? The A-4 cooling system is almost entirely carbon steel which will freely rust in salt or fresh water. Salt water will precipitate salt crystals at high temps and I recall acid flushing the system when I had one but it seemed to me the only way to stop the rusting was to close the circuit and go to freshwater cooling where you use antifreeze with a corrosion inhibitor. Even then I guess you would still get some rust as evidenced in my freshwater cooled 5432 Diesel which has a little scale in the freshwater side of the exhaust manifold.