Cross threaded spark plug

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what2do
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Re: Cross threaded spark plug

Post by what2do »

Must be my paranoia but I'm thinking the op may just try a temporary fix until a helicoil is available. I just hope that if the temp. option is wrapping some ptfe around the threads, then start the engine and have a look.................for heaven's sake, hold your breathe as ptfe is highly toxic when melted. It'll make you madder than a hatter and you may end up purchasing a t25 - oops, too late for that!!!
Why would the glass be anything other than half full?

'89 panel van, 1.9 DG.

what2do
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Re: Cross threaded spark plug

Post by what2do »

Has anyone ever known of a helicoil winding out with the plug/bolt? Theoretically it shouldn't because after being wound in, the little tab snaps off (remaining in the sump in my case!!!) leaving a very very sharp point that is supposed to dig into the comparatively soft ally, mild/cast steel.

Cheers, Mitch.
Why would the glass be anything other than half full?

'89 panel van, 1.9 DG.

jamesandtheopenroad
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Re: Cross threaded spark plug

Post by jamesandtheopenroad »

what2d wrote:Must be my paranoia but I'm thinking the op may just try a temporary fix until a helicoil is available. I just hope that if the temp. option is wrapping some ptfe around the threads, then start the engine and have a look.................for heaven's sake, hold your breathe as ptfe is highly toxic when melted. It'll make you madder than a hatter and you may end up purchasing a t25 - oops, too late for that!!!

Well the van is still running well so it's not an immediate problem, but thought I might try a little ptfe tape and/or some high temp sealant on the mating surface of the washer until I can find a garage/engineer I can trust to helicoil/temp-sert it.

However, may now give the ptfe option a miss...
"our doubts are traitors, and make us lose the good we oft might win, by fearing to attempt" Mr W Shakespeare

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what2do
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Re: Cross threaded spark plug

Post by what2do »

I wouldn't dictate that you don't use ptfe, just don't inhale whilst viewing.
Why would the glass be anything other than half full?

'89 panel van, 1.9 DG.

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BOXY
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Re: Cross threaded spark plug

Post by BOXY »

I had a plug launch out of a Renault 5 whilst driving and it dented the underside of the bonnet. Don't get too close to a running engine with a iffy plug thread. From what I can remember I took the head off and got a local engine builder to heli-coil it for me for about £20.
2ltr Aircooled CU with twin Solex's & originally a 009 dizzie, but now back to standard.

what2do
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Re: Cross threaded spark plug

Post by what2do »

Jeepers, that's what you call a wake up call!!!!!!!!!!!!!

BOXY wrote:I had a plug launch out of a Renault 5 whilst driving and it dented the underside of the bonnet. Don't get too close to a running engine with a iffy plug thread. From what I can remember I took the head off and got a local engine builder to heli-coil it for me for about £20.
Why would the glass be anything other than half full?

'89 panel van, 1.9 DG.

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BOXY
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Re: Cross threaded spark plug

Post by BOXY »

It was only a 850 L. The performance wasn't effected, just the engine noise changed.
2ltr Aircooled CU with twin Solex's & originally a 009 dizzie, but now back to standard.

Allanw
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Re: Cross headed spark plug

Post by Allanw »

kevtherev wrote:A time-sert would be better as there's no drilling and the coil wont come out when the plug is removed the next time it has to be changed.

Good man - I was just going to post: "Helicoils suck a***!"

The problem with them is, that they try to expand on the way out - IF they do, you often knacker the hole entirely. All it takes is carbon build up on a plug, and they can move.

I've never had a timesert come out, but I have removed a couple. If a timesert does come out, they aren't trying to expand like the spring type helicoils do. The hole stays usable, reducing the likelyhood of requiring a whole new head!

The timesert is far more dimensionally stable (why is there no :Geek: smilie?)
Allan :-)

'84 T3 Kombi, EJ25 DOHC.
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edoh
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Re: Cross threaded spark plug

Post by edoh »

is this clack n rubbish?

http://www.fine-tools.co.uk/engineering ... _1857.html

http://www.carsdirect.com/car-repair/ho ... epair-tips
Owner of a red T25 fixed hi top campervan - colour - spikey red - petrol - water cooled - 1.9 dg engine rhd - 1990 g reg n still going strong!-

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