I have a delta model 1600 single lever bath faucet. There is no hot water at the mixing valve, cartridge.I have removed the valve and cleaned everything. I have hot water to the shut off valve on the left side of the faucet.there is a blockage between the two that I can't free up with a wire or air pressure. The cold water side works good and I can blow air through it. Any idea what the blockage is,or how to remove it without distroying the faucet.

Sounds like you have screwdriver stops on either side of the valve body, correct?
Shut the water off to the house and unscrew the large nut and pull out the stem and washer assembly. That way you should be able to get at whatever's blocking the seat. Good luck, Tom