Ejecto Sparkplug

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Ejecto Sparkplug

Postby Ca33ag3 » Sat Jul 18, 2015 3:15 pm

hey folks I am getting this problem seen to by my mechanic mate in a months time but I wonder if this is a common problem.

So the other week I was driving along as normal when all of a sudden my mx5 (mk2 1.6) began misfiring, I stopped and looked at rhe engine and seen one of the HT leads was half out of the cylinder and when I took it out to inspect it the sparkplug came with it, after having my mechanic look at it it turns out the screw thread that holds the sparkplug in place isnt there anymore. So I cant put a new sparkplug in and the o ly reason I can put the old one in is because part of the screw thread from the cylinder is on the sparkplugs thread.

Is this a common problem?? The same thing happened to Clarkson on top gear and ive seen repair kits exactly for this out there and if it is common anyone got any tips For when we are fixing it??

P.s. I am driving my daily in the meantime while my mx5 sits in my garage

Cheers folks :)
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Re: Ejecto Sparkplug

Postby drumtochty » Sat Jul 18, 2015 3:59 pm

It is not an MX5 problem but happens to all cars from time to time and the main people to sell kits some years ago were Helicoil.

It is a standard job that a garage will do two or three times a year.

I would use a garage who have done it before as it is easy to get it wrong
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Re: Ejecto Sparkplug

Postby Ca33ag3 » Sat Jul 18, 2015 8:02 pm

Had no idea this was a problem with all cars, I rang up my mechanic and he said he'd never seen or heard of it before and hes been in the buisness 20 years, the guy who is doing the repair for me is a qualified mechanic and apparently hes dealth with this problem a couple of times when he was serving with the army as a mechanic
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Re: Ejecto Sparkplug

Postby mgrays » Mon Jul 20, 2015 1:07 pm

More common from abused/neglected cars with aluminium cylinder heads (as most cars are now).

Neglected as mechanic did not lubricate the spark plug threads .. few seem to but black grease or copper slip should be used sparingly as when these dry out they leave behind lubricant ... in no manuals I have seen but it is best practices as otherwise the steel spark plugs corrode onto the aluminium head.. most mechanics do not keep a car long enough to see the fault.

Abused by over torqueing the spark plugs when they were changed... or failed as too much force used after they seized as no lubrication as above Neglect.

Well looked after cars that are not washed under bonnet (another abuse/neglect as water gets into spark plug wells and causes the corrosion if first point .. hence lubricate those threads) will not suffer this.. sadly our cars are passing onto those less able to look after them .. and hence failures turn up.
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