BillR

I had alum heads on mine motors for less than a year. They were coated and supposed to be OK in salt. Boat was religiously flushed with in 10 minutes of coming out of water using salt away. NEVER sat in water - ever!

Had to tear down and was surprised at all the corrosion in less than a year (about 25 hours). Don't use them!!!!

Boomer35

+1, ive heard the same story from other guys.

Only way to make them last is to drain them, get the water away from the 2 surfaces. That or Closed cooling, Anti Freeze seems to protect them.

there is a reason Mercury doesnt run Alum heads on fresh water cooled motors, and only on Closed Cooling systems.

Slow Poke

Wow Bill, I have EPD Aluminum heads on mine that Larry worked up before he got out of the biz and they are going on 8 seasons now and I have had 0 problems with any corrosion. I had to pull the port motor this year due to a leaky header that in turn killed the crank and rod and piston on one hole and the heads are super clean. These have been run in the salt 99% of their life.

Sorry you had such a bad time with aluminum, I am not saying you are wrong but what you saw has not been the case with my heads and what I have seen.

rmbuilder

Bill,

Who is the manufacturer of your cylinder heads?

Regards,

Bob

HaxbySpeed

I've heard of a few guys that have had issues using salt away and aluminum. Don't know if it's just coincidence or there's something there..?

BY U BOY

4 seasons on my aluminum heads all in salt and flushed with fresh water nothing else and no corosion. I would build another engine with aluminum heads again with no problem.

Mr. Demeanor

One thing we may be forgetting here is stray current combining with salt and dissimilar metals on some of your boats. That may explain why one boat with aluminum heads holds up great and another doesn't.
Outboard motors have aluminum blocks/heads and seem to hold up very well. They do use some sort of coating in the water passages but its certainly not as tough as military spec anodizing.
I have a 1994 Yamaha 130 on my little tunnel and recently flushed the engine with a mixture of vinegar and water and it really cleaned out the water passages. Dont give much credit to the increase in water pressure as it was more likely due to having a different water source but look at the crap that came out of the engine suspended in the water.

http://www.youtube.com/watch?v=mKu8KkPFRnw

Mr. Demeanor

Flushing with water and vinegar will definitely prolong your aluminums life.

Before

http://www.flickr.com/photos/65811281@N07/6133149278/

After

http://www.flickr.com/photos/65811281@N07/6132602179/

BillR

Not sure, but I "think" Edelbrock..
My buddy (Rogman on OSO) had EXACT same issue. I think he got 40 hours before pulling. Both his motors had same amount of corrosion.
He now has iron eagle heads (I think) and after 3 years they look brand new.
I am not convinced on using alum heads in salt.

JeremyAnderson

The 180cc World cast iron heads work really well. if you are building a strong 347, the 200cc models are capable of 500hp with a good bit of cam.