066 woes

[zimmy]

hi there just got an 066 in for repair with a stuffed spark plug thread.
my question is has anybody done a helicoil repair, if so was it successful.
bearing in mind that here in new zealand a cylinder and piston kit are very expensive.

 

[huskydave]

I have used them on many small engines my friends have stripped. There are several other methods of repairning damaged threads though. I have not had any come back after a helicoil job. I would suggest getting a machinist show you how to do your first one If you decide to fix it that way. In some cases I drill and tap 3 sizes bigger than the damaged thread and thread a solid plug in and redrill/tap back down to the right size and this works excellent too.

 

[Lakeside53]

I've seen many plug helicoil repairs on chainsaws and none have been successfull over the long haul, and some don't last at all. It's a very short thread... There are better solutions, but those that require loctite to hold the thread insert won't work due the temerature at that point. There is a system that uses pin to lock the insert, but I can't remember the name.

I'd take it to a machinist (off the saw) and get it done correctly. TIG welding and then retapping the threads can work well.

 

[Jacob J.]

At our shop we use "Thred-Sert" and "Time-Sert" brand inserts for replacing entire threaded portions. They seem to hold up well in spark plug hole repairs. You have to be careful tapping the pins in though, and have a small punch handy for recessing the pins.

 

[Tzed250]

Keen-sert is a brand that uses retaining pins, though i have never used them.

My experience is with Helicoil:bang:

And with Time-sert

 

[zimmy]

thanks for input guys, have sent it off to the machine shop to be repaired,never done a helicoil and was a bit loath to tackle it.saw only two years old.

 

[Lakeside53]

let us know what they did