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Discussion Starter #1
...not on the Mustang, but our little Mazda B2200 has a stripped spark plug hole. I got a kit with the tap, and the solid inserts, but if anyone can give me any tips before I do this, I'd love to hear them. What's the best way to keep filings out of the cylinder? I was thinking about packing the flutes of the tap with grease, and then turning the engine over without the plugs in it when I was finished to blow out any left-over crap. Does this sound like a good plan?

Also, how much of a pain will this be to do? It's an aluminum head, so I'm hoping it shouldn't be too bad, but I've never done one before. Thanks in advance for any suggestions/words of encouragement.

-Brian
 

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I would yank the head to do this..those little shavings are going to go all over the place..this is really the sorta job I would farm out..it should be done on a drill press..I had a similiar prob on a motorcycle..aluminum heads..it was drilled and a heli-coil was put in..but I had it done at a machine shop..

'59 T-Bird..[color:blue]'70 Mustang Convert</font color=blue>...[color:green]'72 Mach One</font color=green>
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Discussion Starter #3
Crap... You don't think the grease will catch most of the shavings? This is the tip I've always heard when running a tap in this manner (like in an oil pan without pulling it, etc.). With the kit you don't drill it out at all. The tap is long and tapered, so it starts out by slowly reaming the hole to size, and then starts cutting new threads. Also, the inserts are solid, and are supposed to be better than a heli-coil.

The head would really be a PITA to remove. I was thinking about calling around to see how much somebody would want to put the insert in, but I'm not so sure I'd trust them to do a better job than I can do myself... Anybody else have any opinions?

-Brian
 

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The spark plug solid inserts are definitely stronger than a HeliCoil. The kit should come with a tap, the inserts, LocTite, and instructions. If you do use grease, make sure you remove all the grease before you LocTite it in, otherwise the LocTite won't hold.

You could use compressed air thru the PCV port to create a positive pressure in the cylinder to keep particles out. Make sure the intake valve is open.

[color:blue]
1967 Acapulco Blue coupe
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Torq-Thrust "D" 225-60-14
1968 PDB, Corbeau
LeCarra, Alpine in-dash CD
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Discussion Starter #5
Thanks for the advice. There were no instructions with the kit, but I had the basic idea already. What number Loctite would you recommend?

-Brian
 
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Discussion Starter #6
I have no experience with stripped plug-threads (knock on wood) but I do know that you have to keep the filings out of the cylinder at all cost.

When tapping the thread turn one revolution clockwise followed by a semi-revolution counter clockwise to clear the filings from the tap threads. Repeat this until the whole thread has been tapped. Use a cutting compound and take it easy, you don't want the tap to snap when it's in the thread.
The filings will be released upwards by the tap where you can suck them up with a powerful vacuum cleaner.
 

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Do a search on Yahoo or your favorite search engine for "spark plug thread repair". I came up with quite a few. Here are some:

http://www.xs11.com/tips/repair/repair27.htm

http://www.timesert.com/howtosp.htm

http://www.wetspotracing.com/wet2.html
This place charges $25 to repair a stripped spark plug thread.

[color:blue]
1967 Acapulco Blue coupe
302 4V, C4, 9" 3.25:1
Torq-Thrust "D" 225-60-14
1968 PDB, Corbeau
LeCarra, Alpine in-dash CD
http://www.geocities.com/mlnielsen_67/index.htm
WEBSITE UPDATED 3/25/01
</font color=blue>
 
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Discussion Starter #8
If its an older mazda (not fuel injection) those little engines are more simple to work on than an old 289. I just rebuilt one for a friend.... If it's the older kind you could take the head off tap it and put it back on in half a day. Just mark all your vacuum hoses cause there are alot.

68 Fastback.
 
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Yeah, it's not EFI, but it has a computer controlled carb., and there would be a zillion vacuum lines and smog crap to deal with. I could definitely do it, but I don't think it's worth the trouble. I think I'm going to go ahead and use the grease on the tap, and use compressed air to blow out the cylinder when I'm done. Wish me luck.

-Brian
 

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You might buy a magnetic pick up tool, slim enough to fit in the hole to pickup any metal particle the grease doesn't grab.

Jeff
Member: Flatheads ain't so bad association
Never trust an over 40 Chevy owner association (They have to cheat to win)
 

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Oops! Thinking Mustang, not Mazda.....Oh well

Jeff
Member: Flatheads ain't so bad association
Never trust an over 40 Chevy owner association (They have to cheat to win)
 
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