Helicoil

[bfullmer]

Have johnsored chain saw that spark plug hole is stripped out ,
will a helicoil hold up?? Tsc says you have to buy a whole
rebuild kit , can you buy just a head ??

 

[dzc3]

a helicoil will work very well

 

[MarkB_MI]

A helicoil in aluminum is stronger than the original threaded hole.

 

[Greg_Ky]

Heicoil will work but for spark plug threads nothing comes close to a Time-Sert.
Poke here

 

[Indiana Ken]

There are various types of repair inserts. Heli-coil is but one. Typically you need to buy the kit which consists of the inserts, installation tool and a tap. I like the KD kit since it uses a shell type insert and the tap reams the hole and taps it for the insert in one operation. Be sure to coat the tap with grease to catch the chips if you are not removing the head or if the head is one with the block.

The inserts make a good repair - IMO. If you don't want to buy the tool take it to a shop, they should have the tools and inserts. The insert should not change the heat range requirement for the plug - use the same plug as per OEM.

 

[Gene Davis (Ga.)]

I have one of the older helicoil sets and it reams
and taps with the same tool in one time through.

 

[T.R.K.]

Been told that you can helicoil the head. Never witnessed it.

You should be able to helicoil the head if it is a pretty late model Johnsered. Find a servicing dealer.

 

[LarrySTN]

Heli coil will work but I much prefer a time-cert or other similar insert as they have a flanged area at the top for the spark plug gasket to seal against. I've seen heli-coil used and the heli-coil come out when the spark-plug is taken out for replacement.

 

[Bob M]

I had my local mower shop install E-Z Lok inserts to repair stripped out plug threads in mower and generator engine heads. The inserts are more durable than the original tapped holes.

As I recall cost was about $20 each.

 

[Steve@Advance]

A coil thread insert (Helicoil is a brand name) will work for a spark plug. Problem is trying to hand drill and thread and keep it straight will be next to impossible.

There are 2 types of spark plugs, compression gasket and taper seat.

If it's a compression gasket type, and the head can be removed and the hole can be indicated straight, as in Bridgeport mill, an insert can be successfully installed. The compression gasket will still seat on the head surface where it originally seated. See the importance of keeping it straight?

If it's a taper seat plug, when the striped hole is drilled and tapped oversize tor the insert, you will loose the seat area. Possibly a compression gasket plug could be substituted.

Have you looked for a used head, as on Ebay?

 

[Russ from MN]

I think the head and the jug are one piece, at least on the older ones.

 

[johnlobb]

I wish I would have known about the Time-Sert. This website is a real teacher!

 

[riccumming]

cant beat a TIME SERT get it on line been useing them in fords for years never had one fail

 

[El Toro]

Take it to a local auto machine shop. I had one installed on my Toro Whirlwind mower. Cost was $10.00. That was 10 or 15 years ago. Hal