heat problem...heater core or blend door??

[rlith]

yes...

[Jerry80871852]

The drain plug on my 92 S-10 4x4 Blazer is all the way towards the bottom on the drivers side.

It is plastic and inset just a bit.

One can not see it from the top, but if you reach down it there it will feel sort of like a plug at first, but if you feel around with your fingers you will find the flat piece for screwing it out, I had to turn mine about 4 turns or so to get it competely open day before yesterday when I was flushing my cooling system out.

And it did not turn very easy either, pretty tight, plus it is hard to get a good grop on it.

[vtmecheng]

If you suspect the head gasket first do a compression test.