Need some ideas here. I installed the head and torqued everything down. Before I put everything together, I decided to do a cold compression test and the result is NO good.

cyl 1 - 300
cyl 2 - less than 50.
cyl 3 - 350
cyl 4 - 200
cyl 5 - 300
cyl 6 - 100.

The engine was running but missing at idle. I should have done a compression test first before I pulled the head. I did not so I do not know what the reading was like. I did compression test on this engine 1 year ago and the result was good. I have a few questions:

1) How can cyl 2 be so low? The head is bad or the block? Put 2 spoonful of oil thru the inlet valve and the compression goes up a little bit to about 80.
2) Anything I can check before I pull the head again?
3) I have another #14 head. It is from the car where the oil pump chain snapped and buggered the engine. It is a good head as the car was running. Shall I try to install this head?
4) Can I reuse the Head Gasket? It is torqued down but never used so to speak.

Any help is appreciated.

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