well looks like my orig one on my 350 has a small crack in it. I have one off the 455 Im getting ready to build, but it is rusty and needs attention. I know I could just order a new one, but what fun is that. I was thinking of sandblasting it clean, but started thinking that it would just rust on inside with water constantly touching it. Is there something I can put on it to protect it from water or should I just order one and forget fixing what I have?

Thx

 

Rusty?

Aren't they all aluminum?
Was it aftermarket or did olds make steal ones?

 

I believe Olds made steel ones as well. I also have one that was rusted and pitted. I just used a wire wheel to clean mine. It looks great.

Truthfully, those thermostat housings are so heavy duty you don't really have to worry about them flash rusting. Just clean it and throw it on there.

 

The ones without the metal J tube are cast iron. The others are aluminum or zinc.

If you're worried about rusting keep in mind that the entire inside of your block and heads are made of the same material. Good antifreeze has a rust inhibitor in it. I just sandblast the outside of the tstat housing and paint.