Page 1 of 1

Leaks Between Spark Plugs & Head

Posted: Wed May 08, 2019 9:55 am
by David Tipton
I have a 1915 Touring with the original head. I had the motor and transmission rebuilt about 4 years, alum. pistons, scat crank, stainless valves & seats, etc. Yesterday when I drained and refilled the radiator some accidentally splashed into the 1st and 2nd spark plug dimples on the head. When I started to crank the motor I saw bubbling around the spark plug threads, I tightened the plugs as much as possible but to bubbling is still there. This is happening around all 4 plugs even after tightening. I don't think this is a new problem I happen to notice it because I splashed coolant on the head while refilling.

The plugs are new Champion 25's. I would appreciate all suggestions/help.

Thanks,
David Tipton
Colleyville, TX

Re: Leaks Between Spark Plugs & Head

Posted: Wed May 08, 2019 9:58 am
by Charlie B in N.J.
Actually kind of common. You'll hear everything from Teflon tape (white & Yellow) to tin foil on the threads. Yellow Teflon is my choice.

Re: Leaks Between Spark Plugs & Head

Posted: Wed May 08, 2019 10:18 am
by Steve Jelf
It's a problem only if it lowers compression or if you let a lot of water leak into the cylinders, but foil or Teflon tape are OK. Some are afraid the tape will unground the plugs, but the threads will cut through it and contact the head.

Re: Leaks Between Spark Plugs & Head

Posted: Wed May 08, 2019 5:19 pm
by George N Lake Ozark
I had the same issue on my Z Head. I have used tin foil but had issues removing the plugs. I use anti seize now and no issues. A few years back, Champion made some new X's with bad threads that would leak. The new ones I'm running don't have that issue but did have seepage on the Z Head. Anti seize works for me.

Re: Leaks Between Spark Plugs & Head

Posted: Wed May 08, 2019 7:00 pm
by KirkieP
George
Anti seize works good for me too.

Re: Leaks Between Spark Plugs & Head

Posted: Wed May 08, 2019 7:50 pm
by David Tipton
George N Lake Ozark wrote:
Wed May 08, 2019 5:19 pm
I had the same issue on my Z Head. I have used tin foil but had issues removing the plugs. I use anti seize now and no issues. A few years back, Champion made some new X's with bad threads that would leak. The new ones I'm running don't have that issue but did have seepage on the Z Head. Anti seize works for me.
Any particular brand of Anti Seize?

Thanks,
Dave Tipton

Re: Leaks Between Spark Plugs & Head

Posted: Wed May 08, 2019 7:52 pm
by David Tipton
kirkiep wrote:
Wed May 08, 2019 7:00 pm
George
Anti seize works good for me too.
Thanks for your recommendation of using Anti Seize, any brand in particular?

David Tipton

Re: Leaks Between Spark Plugs & Head

Posted: Thu May 09, 2019 9:51 am
by KirkieP
What ever the Parts store has in stock.

Re: Leaks Between Spark Plugs & Head

Posted: Thu May 09, 2019 10:00 am
by hah
Cooper.... takes the heat...use it on engines I have rebuilt ..non t.

Re: Leaks Between Spark Plugs & Head

Posted: Thu May 09, 2019 10:39 am
by Mark Gregush
I use ether anti-seize or white teflon tape, which ever I have at hand at the time. I have some old anti-seize with lead in it (known in California to cause all kinds of nasty things to the body if you eat it! :lol: ), but as said above what ever brand.