striped spark plug hole

[Maahs13]

so my carbide stalled and i checked it over to see the spark plug out, when i went to put it back in the cheap cap broke so i went out and got a new NGK racing cable (all they had) put it in and after 10 min. of riding it happened again put it back in and it shoot right back out from the compression.

So what should i do new head, tap and helix coil , tap and bigger plug?

Another question are these heads aluminum coated?

[alsdaboss]

http://www.thorintl.com/Keenserts-Keyserts-Keylocking-Inserts.htm. just follow the insructions, i recommend removing the head before you do it.

not coated, made of.

[PatNY]

This might help

http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=66033

[JakeTheSnake]

I myself am not a big fan of helicoils and/or inserts. Back in the day I had an Allis Chambers Terra Tiger (6 wheeler) with a JLO Rockwell engine in it. A buddy was helping me with some engine work on it, he over torqued the plug and stripped it. I went the helicoil insert route, it was done right, tapped, measured and all that, and it lasted a day. On these machines the engine sat straight up and was literally between your legs and you leaned over it to grab the handle bars. (Yep, Terra Tigers were the only 6 wheelers I ever saw with handle bars instead of control levers, but I digress! lol) Anyway a spark plug zinging right past my chin at full compression was enough to for me to whip out the old Traders Guide and start looking for JLO engines for parts. I say if your gonna pull the head anyway to do the helicoil insert, just replace the head.

[olderthan]

i replace the head
olderthan

[ckau]

Firstly, put in the correct plug. That nkg you mentioned is a cold plug with a short reach and a different type of sealing ring. It would have threaded in but probably not be sealing properly. If the threads are stripped, replace the head. Any thing else you do to a aluminum head will only be temporary. Aluminum heads will not hold any sort of helicoil insert very long due to different heat expansion rates between the head and the coils.

[alsdaboss]

had a keensert in my wifes audi engine for 4 years, worked great. thermal expansion is no different between the head and keensert, and the head and a sparkplug, and should not be an issue. helicoils should not be used in a cylinder head, as they are a temporary repair, and do not provide a seal. they work in a pinch, but a keensert will save a head from being scrap.

[BuggyMaster]

ckau is right, just replace the head. They are not that expensive. Plus, to do the heli coil you have to generate a bunch of aluminum filings. Guess where they go. Changing out the head is not that difficult.

[Maahs13]

i pulled the head and brought it to a shop and they fixed it for $25 i was going to get a new head but didn't want to wait for shipping and wasn't sure of how i was going to change the valves

[chuckorlando]

What did they do to it to fix it? I would have contacted Tom Syc and either got a large port head or a ported and olished head my self. But then again I like to up grade as needed as well

[BuggyMaster]

I am curious as to what they did to fix it as well.

[olderthan]

i would also like to know what their repair was

[Maahs13]

it was a heli coil i would have ordered a new one or an upgrade but it wasn't in the budget and i didn't want to play around with the valves or wait for shipping
i asked him if it was a guaranteed permanent fix and he said it was and they used them in cars all the time