Stripped Spark Plug

[LOUVETTE]

i WAS CHANGING THE PLUGS IN MY 89..........NO PROB TILL I GOT TO I THINK ITS NUMBER 2 OR FRONT PASSENGER SIDE UNDER AIR COND. SOMEONE STRIPPED IT OUT.....WHEN IT DIDNT FEEL RIGHT AND I DIDNT GET ABOUT 6 TURNS BY HAND LIKE THE OTHERS JUST ABOUT 3...I LOOKED AT THE PLUG I TOOK OUT AND SAW METAL SHAVINGS ON IT.....WELL I MADE SURE IT WENT IN STRAIGHT AND TURNED IT ABOUT 3 BY HAND THEN WAS ABLE TO TIGHTEN IT UP ....SEEMS OK....BUT....I JUST DONT LIKE THINGS SCREWED UP....HOW HARD IS IT TO FIX THIS PROBLEM.....HEARD ABOUT HELI COIL BUT HAVE NEVER USED ONE........DONT WANT TO TAKE IT ALL APART......LIKE REMOVE THE HEAD ECT....PREFER NOT TO REMOVE THE AIR COND.....COULD LET IT ALONE AND SEE HOW IT GOES....I DID GET 3 TURNS BY HAND OK BEFORE TIGHTNING IT UP OK....WHAT DO YOU C4 EXPERTS THINK NEEDS TO BE DONE.........THANKS IN ADVANCE......AND SORRY ABOUT THE CAPS.....IM NOT YELLING ...JUST MY SOFTWARE AT WORK NEEDS CAPS AND ITS USUALLY ON............

 

[Eagle85C4]

First I would try a tap and or a thread chaser. You just might clean up the existing threads and be alright. Else you will have to take the head off and get it machined. The only other way I know of is to get it heli-coiled. But it looks like you just got your reason to upgrade the heads....

 

[Ken]

LOUVETTE, please take a look at this post: UPPER CASE TYPING indicates SHOUTING .

 

[FrankM]

you will find that someday, at the worst possible time, the plug will blow out of the hole.

You will know by the engine skip and the noise under the hood

 

[BlackNBlue95]

you will find that someday, at the worst possible time, the plug will blow out of the hole.

You will know by the engine skip and the noise under the hood

Yea it will sound like a john dear!!! I know we've had em in the shop like this... If it's in leave it until some thing happens.. just remmber the more you mess with the treads the more of a chance you have to get crap in the cyclender. and can sractch up the bore.. we have helicoiled before and I don't like the idea of doing it on the car I would rather have the head off to repair it because when you heli coil it you have to drill the hole tap it and run the heli coil in.. when doing this obviously you get some metal shavingings in the cyclender.. not good.. and taking the heads off is not hard just takes some time..
-Rick

 

[rrubel]

Helicoils are great for low-pressure situations and on cast-iron, but I used a couple on the exhaust manifold of a turbo Subaru (aluminum) and after a couple months they stripped worse. The combination of aluminum and heat and pressure killed 'em. On that car, when a shop stripped the plug hole (*never* try to change a plug on an aluminum engine when it's hot!), they had to tap and sleeve the hole (it's like a helicoil but solid - not a spring).
[RICHR]

 

[BlackNBlue95]

Helicoils are great for low-pressure situations and on cast-iron, but I used a couple on the exhaust manifold of a turbo Subaru (aluminum) and after a couple months they stripped worse. The combination of aluminum and heat and pressure killed 'em. On that car, when a shop stripped the plug hole (*never* try to change a plug on an aluminum engine when it's hot!), they had to tap and sleeve the hole (it's like a helicoil but solid - not a spring).
[RICHR]

From what I remmber last time we did one it was an aliuminum head I believe it is a special heli coil too.. may have been a sleeve like where totap and run it into the hole.. but I know there different from the regular helicoils.. because the regular heli coild have kinda a tang at the bottom for the installation tool.. which must bebroken off.. andyou dont want that on an on car application because themetal tang would fall into the bore.. I would leave it alone unless it blows out.. if it's in there tight now it will probably hold up..
-Rick

 

[UKVette]

Stripped plug,

In the UK we use a company called 'Wurth', they are European and manufacture a system simillar to helicoil but solid, and they make inserts specifically for spark plugs. I have used them myself and found them excellent, (I work for a Volvo truck dealer). You would have to remove the head as the insert needs the hole to be opened out and re-tapped. The insert has a lip that seat down and locks it in place.
If you need any more info on them, give me an e-mail.

cbrpilot@hotmail.com

Had a plug break off in a Viper a couple of weeks ago, No 10. Managed to get the core and ceramic out then use a stud extractor with a pencil blow lamp to get the outer removed. Over 4 hours to get out, but better than removing the head!

 

[phrogs]

What you gents are referring to are more like rosan fittings where you drill the hole out to size then thread it in, They are way more solid than a helicoil spring type thread repair!

I have used both more than I care to admit!!! "USMC"

We use the rosan fittings on our aircraft parts in some of the hydraulics and jet engine modules they come from the factory with these installed! A lot of heat and high pressure areas


Although If I were you I would remove that head and see exactly what is going on no sense in causing more damage and possible motor damage because of a striped hole!

johnny

 

[Corvette-Pilot]

First I would try a tap and or a thread chaser. You just might clean up the existing threads and be alright. Else you will have to take the head off and get it machined. The only other way I know of is to get it heli-coiled. But it looks like you just got your reason to upgrade the heads....

If you try to do any of this on the car I would suggest that you dip the tap into some grease. This way any shavings greated stick in the grease and come out with the tap vs going into the engine.

You may also want to follow up with a shop vac onto the hole to pull out anything that did go in.

Otherwise you may be better off pulling the head.

My guess from what you said, it may be just a matter of time before the plug is forced out of the hole ?

My $.02

 

[Corvette-Pilot]

We use the rosan fittings on our aircraft parts in some of the hydraulics and jet engine modules they come from the factory with these installed! A lot of heat and high pressure areasjohnny

Hey phrogs,
Sounds like you are an A&P ?
Where are you located?

I went to East Coast Aero Tech a while back !
Never did get into the aviation field.
Seems just as well with how they are doing these days.

Just wondering?