I have always been told that you can't put water onto a hot engine. This summer I have done a lot of deep water crossing with my Kodiak, and have had no trouble so far. But, I've been warned by my fellow riders that I will crack the block if I keep driving through cold water. Is this something to worry about or is the head been developed to withstand opposing temperatures. Has anyone crack there engine block crossing water? Can it happen?

Thanks 1999 Kodiak
Ride hard tread lightly

Your freinds are right for the most part. Any time metal of any type experiences a drastic temperature change, it is going to expand or contract accordingly.
I too trek into the water from time to time. And have not had a problem yet. A buddy of mine had his motor in his blaster sieze on him from a sudden plunge off the bank of a stream. Can't say that he cracked the case, but it did lock the piston and put a nice scratch in the wall of his cylinder.
I would just say to be careful and avoid sudden jumps into the drink. Take it slowly and allow the motor to adapt to the new temperature.

1999Kodiak, you should be fine as long as the engine is not too hot or the water not too cold. The greater the distance between the two the greater the likelyhood that you will crack the engine.

2 strokes are way more sensitive to temperature differences. I don't know if your kodiak is liquid or air cooled, but a 4 stroke liquid cooled is the most resisting engine you can get (talking about water plunging).
But I get my banshee in "cold" water up to the cylinders(the base of the cylinders...not to the head) an nothing broke (yet?)
If your engine is very hot and the water very cold, there will be a risk...but honestly, I really don't think a 4 stroke utility is sensible enough to crack because of water crossing...

I have actually cracked a case. It was on an old yamaha motorcycle. It wasn't really that hot, but the water was really cold. There was a big difference in temperatures. I went in and I saw oil on bank of the stream once I got to the other side. When I looked at the front of the block it had contracted enough that right by the cylinder it opened a 1/4" crack. I am in the water all the time on my blaster and have had no problems yet, but the bike was done for.

I read somewhere on these boards, that aluminum is much more forgiving of temp changes than cast iron, as in an automotive engine.

I do know for a fact that putting cold water in an overheated car engine without the engine running can crack the block.

I think that a liquid cooled quad would for the most part, be pretty safe. You have coolant in the engine that will help to maintain the temerature, or at least slow the cooling of the outside water.

Dave

I have owned four different quads over the past 14 years. They all were air cooled 4 strokes. Probably the most succeptable to the cracking you are speaking of. I have had them hot beyond belief and have gone raging through streams and never had any problems other than the old style mufflers didn't hold up too well.

Four strokes especially water cooled should have no problems with temp changes. From my experience anyway.

Joe

Hey I just posted as cooter, I wanted to keep my atvtime name of joe but it was taken so atvjoe will have to do.
Anyway I forgot to mention that I do a lot of snow riding here in PA in the winter and cold water and snow have never affected my blocks when riding.

Hope you have no troubles either.

Joe