Doing my first head gasket, How does this 3a head look?

[MrWrench]

Hello everyone. Doing my first head gasket/head replacement. I was getting low compression on cylinder 4 (65 psi), lots of smoke and a missfire at lower RPM's. Leakdown test was shooting air out of cylinder 1 and 2 when putting air to cylinder 4.

I purchased a rebuilt head off of another member which I'm putting on. But I am curious as to what you all think about this old head. Do you think this was the cause of my missfire and low compression?
It's not too late for me to rip the engine out and get a rebuild kit because I might have installed the gasket on upside down and drilled the holes backwards from Petros method .

It seems really, really dirty in there. Cylinder 4 is kind of washed out, one of the valves is kinda oily and all the spark plugs have roughly 300 miles on them, but are all fowled out. The old gasket was basically crystalized to the head and the gasket material was very difficult to remove, even with a fine wire wheel and a bit driver.

There's going to be a small flood of pictures coming in hot. Have lots more upon request.
Pictures of the gasket

IMG_20190427_093628.jpg

IMG_20190427_093623.jpg

Pictures of the head.

IMG_20190427_121647.jpg

IMG_20190427_121646.jpg

IMG_20190427_121645.jpg

IMG_20190427_104541.jpg

Pictures of the block dirty

crop_8900743321437024198.png

Picture of the block cleaned up

IMG_20190427_094317.jpg

IMG_20190427_094319.jpg

IMG_20190427_094322.jpg

IMG_20190427_094324.jpg

IMG_20190427_094328.jpg

IMG_20190427_094330.jpg

IMG_20190427_094333.jpg

[jimcrazy]

the wire wheel scares me,,only seen it once but one of the little wires off the wheel went down the oil passages in to the oil pan and went through the screen on the oil pump and lock the oil pump and twisted the dizzy shaft off,,was a 350 chev,we found the wire locked in the oil pump gears

[MrWrench]

I did stuff some rags in the different holes of the block to keep stuff from falling inside. I sure hope I didn't get any in the block. Haha.

The head is still off so I may run a long magnet down some holes tomorrow to see if I can't get some junk out.
Thanks for the tip!

[Petros]

replace all the exhaust valves while the head is off, and replace all of the valve stem seals too. they are cheap, and necessary to make it last longer. Do not reuse exhaust valves, they get weakened by the heat and pieces can break off and do severe damage to your engine.

Not sure what would make air go in #4 cyl and come out 1 and 2 except maybe bad valves. once you get the valves out, you may want to have a machine shop resurface the intake valve faces and all of the valve seats.

[SinusoidalTendencies]

I was always told to not even use Brillo pads, let alone a steel wire brush. just for the off chance of accidentally taking it out of true causing it to need to be surfaced again as well. of course after to many resurfacing's your timing belt wont reach any more.

Let alone the chances of ruining an oil or water pump as jimcrazy pointed out and causing even more of a catastrophe to other systems.



I've used a razor blade. Against better judgment and being advised otherwise, and was just super careful. But it was definitely a bad idea. Hard plastic credit card is not a bad scraper, or copper maybe.