I was thinking of going with an aluminum block but, now am not so sure. How true is this? Or would this only happen in extreme temp changes like, hot engine going through 35*F water? I do the ocasional four wheelin' and do go through some pretty deep water, so this does concern me. Any more input would be great.

 

In theory that could happen to any engine. Hot metal, cold water ... somethings gonna give in that rapid temperature change.

Try this .. get a 100watt light bulb in a lamp, leave it on long enough to get hot. Wash your hands and flick the water drops on it. Be sure to do this outsie though.

We ruined a shop bulb, the $2 indestructable ones by letting some coolant drip on it.

 

I understand that but, you have to admit glass has nowhere near the flexibility of aluminium. My question really is, I guess, are aluminum blocks that prone to damage from cold water warpage or cracking?

 

Flyer is right; it could happen to any engine. I would imagine that it would take a fairly extreme case to crack even an aluminum block. Probably something like blasting though a mudhole turning 5K rpms then splash down in some deep water.

I should point out that I don't have any personal experience with aluminum blocks; thats just what I have heard. Some of my rock crawling buds run aluminum engines to save weight, but we don't play in deep water either.

 

I would like to add that after running through that hole at 5k rpms and before splashing in the deep hole, that the engine would probably have to be overheated as well to actually crack.

 

Thanks guys, I feel quite a bit better now.