I found a burnt valve on number #2 cylinder. The compression test on the original head was 185,80,185,175. On the replacement rebuilt head I got 185,80,80,70. I used new Fel Pro head bolts, sprayed out the bolt holes. I torque it like the manual said. Didn't used copper spray.
I removed the head. # 4 corner of the gasket looks like in may not on seated correctly. How can I get the gasket to seal better?? What are common mistakes done?

 

have the head and bock check for warpage...the max tolerance may be only 0.004 thousands of an inch iirc. you will need a straigh edge and feeler gauge. if its out of spec machining or new parts are the fix.

 

What's the best way to clean the block deck while its in the car.? I think it's cast iron. I don't have air tools.

 

thats good as air tools should never be used to clean the block or head....it polishes off the tool scribing...and you want to keep this. rubber wheels or fiber discs leave particles that can end up in lubrication circuits.

use a razor blade