meirman writes:

Follow-up on the engine with bad spark-plug threads that you were good
enough to advice me on a couple months ago .

The hole was definitely too small for the bigger sparkplugs, so I
decided to go with the helicoil.

The motorcycle shop was willing to do it for 6 dollars for the
helicoil and iirc 30 dollars installation.

Also, on E-bay, I found a lower cost brand, Recoil Fix-a-thred (no a),
and the vendor said it was better because the insertion tool was metal
instead of plastic. And he said that the coils themselves were the
same as the other brand used. Helicoil brand? I think his buy-it-now
price was about 40 dollars and I was willing to spend the extra to
have the tool. (not sure about the price. I don't see them for sale
now, and ebay purged my Watch list of the old items (probably because
they purge completed auctions after 30 or 60 days or something.)

(although now I see a Helicoil brand kit for 12MM with less than 4
hours to go (15:16PST on Saturday) whose current bid is 20.50 dollars
plus 8 dollars shipping. This week there seems to be a lot of
helicoil stuff, but not that one guy. Last time a lot of that one
guy, but little else. )

But I also took the head off the engine to clean inside and I noticed
-- well I didn't notice enough and I'm very confused now -- that even
though the spark plug fell out if placed in halfway and turned it, if
I pushed it in all the way, there seemed to be good threads in the
head at the very bottom (of the head, not the plug).

I feel like a fool, and that I wasted your time. I apologize.
Although I am glad to learn what I did about helicoils, and maybe
telling you about the off-brand and ebay is enough to make up for
wasting your time.

A fool for what? If some of the threads were damaged, a repair was still
needed. It wouldn't be very cool for the spark plug to pop out (probably
rather violently) half way through the lawn.

--- sam | Sci.Electronics.Repair FAQ Mirror: http://repairfaq.ece.drexel.edu/
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