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WTF!!! Crossthreaded spark plug...

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Old 06-16-06, 11:13 PM
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WTF!!! Crossthreaded spark plug...

So, I took my spark plugs out today to check and clean them (still running rich. Hopefully a new coolant thermosensor will fix my cold start and mileage problems), and when I went to put the front leading plug back in, I found it would only go in about halfway (although the outer threads seem fine).

...crap. It still runs (since I had to move it so I could drive my dad's truck to work), but what an annoying problem.

I bought a thread straightener, but in the 5 minutes I had to use it before going to work, it crossthreaded and went in at a funky angle (which is the reason they wouldn't go all the way in, more so than the threads being bad) just like the spark plug did.

I guess I'll have to hold in place to convice it to tap out the threads correctly...

I hate the irony of having your car run just fine until you try to do something else and mess it up...

And yes, I made sure to put antiseize on the other plugs :p

(plus I got my first paycheck today so I get to go spend more money on it, hurray :P )
Old 06-17-06, 12:15 AM
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I would be doubtful the threads could be re-cut without dropping any shavings into the motor.

I would be rebuilding
Old 06-17-06, 01:39 AM
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If all else fails, I could probably pour some water into the spark plug hole, and suck the shavings out with a thin rubber hose duct-taped to a wet/dry shop vac :p

Sounds like a much better idea than tearing an engine apart to clean out a few bits of finely ground aluminum.
Old 06-17-06, 02:05 AM
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Originally Posted by Icemark
I would be doubtful the threads could be re-cut without dropping any shavings into the motor.

I would be rebuilding

the best way to avoid getting shavings into the motor is to coat the tap with axel grease. the grease will pick up the shavings.
good luck
Old 06-17-06, 02:15 AM
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Man that sounds harsh Icemark... sure there's no other shadetree way?

If it happened to me, I'd probably either try the grease idea... or I would rethread it without moving the engine, get as many shavings as I could out by hand/grease... then pump a bit of engine oil into the hole... the idea being the oil will grab and gather the shavings and give them volume... then when you start the car the oil will burn (smoke like hell) but hopefully protect the seals long enough for the amount of time it takes for the shaving to work themselves out... of course this is recommended to be done fast... don't leave the oil sitting in the chamber for a long time.

I'm not recommending this, I'm just saying it's probably what I'd do before going through a whole rebuild... there's a fair chance of not destroying the seals/housing, just a gamble.

--Gary
Old 06-17-06, 03:39 AM
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Yes... the grease is a very good idea.

I hadn't thought of it myself.
Old 06-17-06, 03:48 AM
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hard to believe a spark plug can get the engine rebuilt without even failing by use in the car. Hopefully that won't happen.
Old 06-17-06, 07:58 AM
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wow almost the exact same thing happend to me.. about the time i was finishing up my cosmo re swap

i 'strighted' out the thread's after maby an hour of putting the tap in, taking it out, cleaning, lots of oil etc.

jsut take your time, and dont fight the tap. my car has no problems now, hwoever when i change plugs the rear leading plug still goes in and out a little harder than finger tight, however it will go in every time now
Old 06-17-06, 10:04 AM
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Originally Posted by Bob_The_Normal
Man that sounds harsh Icemark... sure there's no other shadetree way?

If it happened to me, I'd probably either try the grease idea... or I would rethread it without moving the engine, get as many shavings as I could out by hand/grease... then pump a bit of engine oil into the hole... the idea being the oil will grab and gather the shavings and give them volume... then when you start the car the oil will burn (smoke like hell) but hopefully protect the seals long enough for the amount of time it takes for the shaving to work themselves out... of course this is recommended to be done fast... don't leave the oil sitting in the chamber for a long time.

I'm not recommending this, I'm just saying it's probably what I'd do before going through a whole rebuild... there's a fair chance of not destroying the seals/housing, just a gamble.

--Gary
well all you need is one little shaving missed, and you really wreck a housing.

To me it is cheaper to pull the motor, and rebuild it than to try using grease or oil or water, miss one little shaving, rip up a apex seal and a housing and have to rebuild the motor and then replace a housing and a seal set.

But by all means the shade tree mechanics have suggested a couple of ways in this thread on how to try or how they tried.
Old 06-17-06, 01:04 PM
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Huzzah!  It went back in properly! And it didn't blow up when I started it...yet. lol...

I basically just had to apply pressure in the opposite direction that the tap and plug wanted to go (which is to the right). I'm sure next time it still won't go in easily... but better than having to helicoil it, or rebuild.
Old 06-17-06, 01:42 PM
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Originally Posted by Icemark
well all you need is one little shaving missed, and you really wreck a housing.

To me it is cheaper to pull the motor, and rebuild it than to try using grease or oil or water, miss one little shaving, rip up a apex seal and a housing and have to rebuild the motor and then replace a housing and a seal set.

But by all means the shade tree mechanics have suggested a couple of ways in this thread on how to try or how they tried.

shade tree ?
Old 06-17-06, 01:55 PM
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this must be a semi common prob, i have run into it on 2 occasions myself. i would have done the grease thing, but i would have used a hose in the plug hole to find the rotor clocked right to the lower edge of the hole prior for easier clean up and a lower possiblity of a missed peice.
Old 06-17-06, 02:44 PM
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Originally Posted by turbine
shade tree ?
Shade tree mechanic = someone who works on their car under a tree... ie, someone who doesn't know everything about cars, but finds the easiest, cheapest way to fix there car.

also, someone who uses a lot of zip ties :p
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