No Compression

Just before you put it back together,..

A test I always do while a head is off,, is move the crank until you have some space in the cylinders above all the pistons,, pour an approx, equal amt of solvent in each cylinder,, usually an inch or a little more.. Check back occasionally,,

- what you're looking for, is any cyl that looses the fluid quickly,, on a good engine,, cyls will hold equal fluid for hours,, sometimes till the next day.. On an engine with bad rings,, the loss of fluid will indicate which cyls have poor rings, usually confirming what the sparks plugs are saying.. (not in your case)

What you don't want to see is one cylinder, or all those low compression cylinders drain qiuickly,, while the cyl with compression holds fluid for hours or overnite.. (my bets stuck valves)..
It's like a compression test,, looking for big differences between cyls..

The loss of fluid will be an INDICATOR of ring condition and seal..

Oil is ALWAYS changed before returning to service..

hope it helps..

Keep the manifolds together..