Aluminum or cast iron heads?

[34 ford]

Hi,
On a 5.7 omc engine. Is it a bad idea to put aluminum heads on, or would cast iron be better?
Thanks for the help.

 

[Reinell-BRXL-191]

Re: Aluminum or cast iron heads?

Salt or fresh? If salt.. no aluminum...

 

[Scott Danforth]

Re: Aluminum or cast iron heads?

Welcome to iBoats

if you have a heat exchanger - aluminum heads are fine.

if you do not have a heat exchangers, aluminum is ok in fresh water, however not salt water.

 

[34 ford]

Re: Aluminum or cast iron heads?

Hi,
Thanks for the info. guys.
I run the boat in fresh water only. It hydrolocked on me , tore it down and the aluminum heads
had warped. So I will surface them and put back together.
I just thought aluminum heads were a bad idea for marine use.
Thanks for the help.

 

[Scott Danforth]

Re: Aluminum or cast iron heads?

if it hydrolocked, you sucked water thru the exhaust. either bad manifold/riser gaskets, or something else went awry.

 

[Bondo]

Re: Aluminum or cast iron heads?

Hi,
Thanks for the info. guys.
I run the boat in fresh water only. It hydrolocked on me , tore it down and the aluminum heads
had warped. So I will surface them and put back together.
I just thought aluminum heads were a bad idea for marine use.
Thanks for the help.

Ayuh,.... If it's got aluminum heads, What sorta Cam is in it,...

To Big of a cam, will lead to hydro-lockin'...

 

[34 ford]

Re: Aluminum or cast iron heads?

Hi Guys,
Thanks for the feed back.
I have put new exhaust manifolds and risers with all new gaskets and new exhaust flappers.
It has to be hydrolocking because of the wraped heads.
The camshaft is just a stock small block hydraulic lifter cam.
Thanks for the help.

 

[HT32BSX115]

Re: Aluminum or cast iron heads?

The camshaft is just a stock small block hydraulic lifter cam.

Look at that cam carefully. If it's a "Stock" marine, "RV" or truck cam then you're ok. If it's something else, you may be seeing reversion.