Cross-threaded Spark Plug Hole

[USASPRINTMAN]

How do you fix a spark plug hole that has the threads cross-threaded?<br>
<br>
Let's just say this head is on a Dolomite 1850 and not the Stag I just bought (since this is the Dolly board)...<br>
<br>
The new plug is in and it's tight. But I should not have forced it in, and now I regret my mistake. Probably it will be OK if I never take out the plug, but I do need to fix it. <br>
<br>
Cheers,<br>
Richard Truett<br>
<br>
<br>


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[Jon Tilson]

its cross threaded? If its gone in okay and the sealing washer is nipped it will be okay. Next time you take it out you can make a thread cleaner with an old plug...just file a slot in the threads for the crud to go in like a thread tap has. Some copper grease and you may well be lucky.<br>
Failing that its helicoil time.<br>
<br>
Jonners

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[2F45T4U]

Just leave it in there! I'm sure mine would of lasted the life of the rest of the engine if I hadnt touched it!

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[george]

just done a 1.0 corsa thats decided to let the centre electrode go (gm plugs with no milage on them ) nothing to stop it going in the cyl <br>
stuffed piston etc..etc... dont leave them till it missfires !!

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[george]

snap-on do some nice plug re-threaders (loads of grease on it so it catches any metal) if that doesn't work then it's head/s off and to your local eng shop<br>
over here most will not do it in situ <br>


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[samgamgee911]

Hey George, I have heard of this happening to Sprint's in the past. How would you check if it caused damage - would a compression test be of any use?<br>
<br>
Of couse if it bent a valve then you would know right away but what if it put the debris out the exhaust valve - would you be very lucky and need no further action?<br>
<br>
Cheers, just wondering

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[george]

on this corsa i could see down the plug hole and the piston was quite shiny so a lot of contact had been made by the plug bits <br>
(when i removed the head no bits of the plug were present so it gone the way of the exhaust valve) <br>
prior to that after the coil pack was removed no2 was realy oily so the pressure was coming out the plug<br>
i put a new set of plugs in but when i did it was smoking like a good un the bad news was the piston was really stuffed buy the centre electrode dancing around

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[Carsreunited]

When I had one of mine helicoiled on the stag. The guy did it in-situ and started the car without the plug in the new heli-coiled hole. The theory being that any debris would be blown out the hole on start up. Didn't have any problems with it.<br>
<br>


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