Engine: Air leak from spark plug

[corum]

After installing a new upper hose on my 49 Champion, I started her up to check for water leaks. No problem there, but I noticed tiny bubbles leaking out of #1 cylinder where a little leaked coolant had gathered in the plug depression. I replaced the plug with a new one with no change. I also noticed a tiny nick on the edge of the spark plug hole. I checked the other plugs by putting a few drops of water in the plug despression, and #4 is doing the same thing. Is there any way to stop this with some kind of Loctite (for example) product? I first thought of plumbers tape but figured that would not stand the heat.

The engine was rebuilt last year, runs great. Has anyone had this specific problem? Thanks guys for your help.

[Treblig]

Teflon tape??????

[StudeRich]

It would be "Compression" leaking, not Air.
Unless you have a Spot Facing tool to grind a flat surface on the Cyl. Head, it may be time to replace it.

I believe Flathead 6 Cyl. Heads are plentiful.

I assume that the copper Gasket/Washers WERE ON the Spark Plugs?

You could try New Plugs and Gaskets if the damage is very slight.

[TWChamp]

I use anti-seize on the threads, and if it's just a tiny bubble from compression, I wouldn't even worry about it.

[studegary]

Are you using new copper gaskets on the spark plugs?

[christophe]

Don't use any LOCTITE products on spark plug threads unless you want to ruin them. Anti-seize or copper grease are the best on the threads. Back in the days, mechanics used two gaskets on the spark plugs to compensate for such leaks. It might be a good thing to use a torque wrench there.
Nice day to all.