Found Spark Plug crush washers

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Apr 12, 2015 | 08:00 PM

zwede

Thread Starter

Race Director

Joined: Sep 1999

Posts: 11,361

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From: Plano TX

Found Spark Plug crush washers

So I have these aluminum heads that use gasketed spark plugs. And I'm one of those OCD types that constantly inspects my plugs. But the crush washers are one-time use. I kept seeing oil on the plug threads because the gasket was not sealing anymore.

Don't want to throw away almost new plugs just because of the gasket so I set out to find replacements. Not easy. Several hours of googling and the consensus was "not available separately".

But then I found a reference to Champion N678 and lo and behold, there was the elusive washer. Available from both Summit & JEGS for about $30 for a bag of 1,000. Yeah, it will be a lifetime supply.

Apr 12, 2015 | 08:34 PM

Dustup7T2

Terrorizing Orange Cones

Joined: Oct 2007

Posts: 2,572

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From: Northern CO

Nothing wrong by having an ample supply of specific inventory, Markus.

At the least, it's one less item to be concerned about, right?

Plus, you're in good OCD company with some of the rest of us here.

Last edited by Dustup7T2; Apr 12, 2015 at 08:37 PM.

Apr 13, 2015 | 09:56 AM

REELAV8R

Le Mans Master

Joined: Apr 2011

Posts: 6,284

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From: Hermosa

Boy that OCD thing must be a real hassle at times.
I have not once in over 35 years of using plugs on aluminum heads changed the crush washer or even considered it an issue.

I had to take plugs in and out all the time on 2 stroke bikes. Oil on the threads, yes from the two stroke oil in the combustion chamber if idled a lot.
Check mine on the vette fairly often for jetting adjustment or wear, never had oil show up on the threads either. Wouldn't that indicate that excessive oil is getting past the rings to the plug?

Apr 13, 2015 | 10:27 AM

zwede

Thread Starter

Race Director

Joined: Sep 1999

Posts: 11,361

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From: Plano TX

I never used to think about the crush washer either, but a while back I decided to fix my oil leak once and for all. Replaced rear main seal, oil pan gasket and valve cover gaskets. After that I still had a stubborn couple of drops that just wouldn't stop. Finally traced it to oil being pushed past the spark plugs. Replaced the plugs and since then it's dry under the car.

Oil consumption is more than I'd like but not excessive. About 1 qt every 1,000 - 1,300 miles. Since all my driving is short distance it's acceptable.

Apr 13, 2015 | 11:55 AM

mikem350

Melting Slicks

Joined: Feb 2006

Posts: 3,105

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From: Sunrise FL

Maybe the threaded plug holes are slightly oversize? Or try a different plug mfgr?

Try a little anti-seize, its thick and might help both in preventing seizing and leaks too.

Apr 13, 2015 | 04:07 PM

marshal135

Safety Car

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From: Madeira Beach, FL

2024 C8 of the Year Finalist - Unmodified

2024 C2 of the Year Finalist - Unmodified

2023 C2 of the Year Finalist - Unmodified

2020 C3 of the Year Finalist - Unmodified

they make a great stocking stuffer

Give 8 away on the forum at christmas time
and till have 2 life times worth.

Marshal

Apr 13, 2015 | 04:09 PM

7T1vette

Team Owner

Joined: Jan 2006

Posts: 37,637

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From: Crossville TN

Most of today's spark plugs are not machined with precise tolerances...especially the angle on the plug base. If it is not correct, it won't seal well and the crush washers are needed.