1995 s10 I took this whole thing apart and marked and labled everything. Now i have an aluminum head sitting on a bucket that was spraying water right from the head gasket but the head gasket is in perfect shape, and there are no cracks i can see on the head. One more thing, the truck would not start up with water in it, but it would when it was drained, like it was blocking the spark or something. yes it did overheat has this ever happened to anyone else, and any ideas? Thank you.
The parts are not straight. Check with an aluminum ruler in all directions.
its not the head gasket, thats what i had thought too. its actually the intake manifold gasket. GM did not design them to resist DEXCOOL, so they disintegrate in a few years. Gm had a lawsuit concerning this. You need to remove the intake manifold if you haven't already and replace the gaskets with quality gaskets from autozone. You will need to remove the distributor, so be sure to mark it. good Luck might be a good idea to replace all hoses, and water pump while your at it
your head is probally warped,,what happens is that the aluminum warps when it gets HOT, more so than your iron block,creating a gap that your water flows through into your cylinder/s. If you get a straight edge and hold it across the surface of your head, you will see light shining through where the surface is warped,[a little bit is a LOT] You can take your head to a machine shop and have it resurfaced [as long as it aint too bad] or else you will need a new head. Sounds to me like your gonna need a new[pickpull ect] head.
Could be 1 of 5 things Blown intake gasket Blown head gasket Cracked head Cracked block Warped head. Most of the times you will not see a crack with your eyes. The head needs to be magnafluced or pressure tested to see if theres a crack. Check your phone book for machine shops. An engine machine shop will check a head for cracks for around $20-40 per head To check if its Warper you can do that with a true flat, straight edge like a long steel rule, and a feeler gauge. Lay rule on bottom of head where gasket goes (all traces of old gasket cleaned off 1st), Try to slide a .001 feeler gauge under rule. If warped a machine shop can mill head flat for around $35-50 per head
Check the flatness of the head with a straight edge and feeler gauges, or take it to an automotive machine shop to be checked. The reason overheating causes head gasket leakage is that aluminum expands almost exactly twice as much as iron when heated, so the aluminum heads buckles upward (warps) when it expands too much more than the block. That is why the engine did not fire with coolant in it - the coolant was getting on the spark plug. Eduardo is right about Dex-cool, but your 1995 probably never had it... I believe GM started that debacle in 1996.