Air leak from helicoil ??

[Stihlsmoking]

So I'm looking at an older 020av as a favor. I get it torn down vac/press check fails both only leak I can find is from this thread repair at spark plug ?
Is this enough to score piston? Thanks

 

[dall]

jeremy that helicoil looks like *s-word and should be a solid insert not just the wire type

 

[Stihlsmoking]

jeremy that helicoil looks like *s-word and should be a solid insert not just the wire type

Kinda what I thought. Then I was thinking the air leak is not that bad cold but after heating up it's probably a lot worse ?

 

[Lee H]

I've used those wire type a million times and have never had a problem.
Does the plug have the gasket on it? That's where it would seal.

 

[Stihlsmoking]

I've used those wire type a million times and have never had a problem.
Does the plug have the gasket on it? That's where it would seal.

The one he had didn't so I tried one with seal still leaked ? Think I'm just going to try a solid insert and retest ? I've had good luck with them.

 

[67L36Driver]

Spark plug threads always seem to leak at least a little bit.

The 'gasket' is there for heat transfer.

Back in the old days, plugs came with a dead soft copper gasket. They sealed good.

 

[backhoelover]

Spark plug threads always seem to leak at least a little bi.

The 'gasket' is there for heat transfer.

Back in the old days, plugs came with a dead soft copper gasket. They sealed good.

good ole days when they made stuff to last

 

[Adirondackstihl]

That helicoil is original to that cylinder.
All the older STIHL cylinders had them.

 

[Stihlsmoking]

That helicoil is original to that cylinder.
All the older STIHL cylinders had them.

Is it common for them to leak ? I couldn't find a leak elsewhere? Thanks

 

[Al Smith]

I'll tell you what might work although I've never tried it . If you have a set of gasket punches you might be able to punch out a sheet lead washer .The head area won't get hot enough to melt the lead and it might seal .John Deere years and years ago used lead washers on cylinder head bolts .If it does work every time you change the plug it will take a new washer .It would be interesting to find out if it does work .