New engine or something else?

I bought my SUV at the end of Jan this year. It has 74,000 miles. I haven’t driven it many miles and in April the service engine soon light started flashing. I had no trouble with it up to this point. It was running great. It was leaking fluid (oil) underneath and the water reservoir boiled over. It was smoking out the tailpipe like it was a steam engine. The mechanic looked at it and it had water in the pistons. The mechanic put something called K Seal (sp) in the reservoir and it has been ok for a week and a half. I know this isn’t a long term fix, but am wondering if I need a new engine or just gaskets?

My guess is that your mechanic poured in K & W seal. I used this in my first car-a 1947 Pontiac. I had the same problem with steam coming out the exhaust. When I removed the cylinder head (very easy on a flat head 6 cylinder engine), I found that the engine block was cracked around a valve seat. I put the head back on with a new head gasket and followed up with the K&W seal. I had no more problem in the time I owned the car even though I knew it was a temporary repair. If your problem is a head gasket, it isn’t fatal and should be repaired properly. If the mechanic believes the engine block is cracked, then just ride it out.