Technical Spark plug question.......

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Technical Spark plug question.......

Iggy1970

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My wife has a 55 1.2 Eleganza which I bought her for a song (just £1,900!) from eBay. It is a nice nmetallic blue and has alloys, aircon, roofbars etc. etc. and runs like a dream with 52K on the clock. I drove it back the 200 miles from Glasgow without a missed beat.

However, it came with no service history whatsoever, the guy I bought it off said he had done it himself and at that price I wasn't complaining.....so for piece of mind I took it to a local independent garage for a once over and a cam belt change and they suggested that whilst the oil was quite clean and the brakes had been maintained etc. etc. they couldn't change the plugs because they were extremely tight and they were worried about snapping them as they are so small(?). It is still running well but I suspect that the plugs are factory fitted and therefore have over 50K under their belt so could do with replacing......

As a former aircooled VW owner I am well aware of the problems of stripping threads on heads removing plugs (they have a soft alloy block and it is a common problem that required taking the head off and helicoiling ) but I have never considered snapping plugs. Is this a problem with the Panda's? Should I just use a big bar and give 'em a bit of welly? Maybe it might be easier when the engine is good and hot?

Any ideas?
 
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they couldn't change the plugs because they were extremely tight and they were worried about snapping them as they are so small(?). It is still running well but I suspect that the plugs are factory fitted and therefore have over 50K under their belt so could do with replacing......

Any ideas?

Been there, done that.

Had exactly this happen on my Ford Ka the first time I serviced it. The problem is that the steel wall of these small diameter plugs is rather thin, and will snap in torsion if it's not sufficiently strong to cope with the torque needed to remove the plug.

Gets worse the longer they've been in, both because the threads tend to seize (just like your VW) and also because the plug walls corrode at just the point where they're inherently weakest.

Soak 'em overnight in WD40 or similar, but clean the surplus off before trying to remove them, so's you don't drop any crud into the cylinder when they come out.

If they do break, and you are lucky/careful, then the whole of the ceramic insulator & central electrode will come out, leaving just the sheared outer wall of the plug in the head - which you can then remove easily enough using an appropriately sized "easy-out". Covering the easy out with a small piece of well greased lint free cloth helps to catch any swarf.

If you are in any doubt whatsoever that something hard has dropped into the cylinder, then without a borescope & suitable retrieval equipment, it's a head off job.

Sheared 2 plugs on the Ka when almost new @ 15k miles; didn't need to take the head off & the car's now done over 100k without any engine problems.

Smear them with a little anti seize when you put the new ones back & you'll avoid any future problems.

Removing them hot may help, as the aluminium head will expand at a different rate to the steel plug, but perversely, they may equally well come out better cold. Sometimes using an impact tool can work better than applying a steady force, but against that impact tools don't have quite the same feel and if it does break, the vibration may mean it's more likely something unwanted may end up in the cylinder.

Good luck, whatever you try.
 
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I'd have a go at getting them out while hot, I'd rather strip a thread as it's fairly easy to repair than snap one or all of them off.

Soak them over night with WD40 first, get the engine hot, but don't respray when hot, it'll just cool the head off around the plugs and us a good fitting plug spanner and a long bar to "crack" them quickly.

Steel into alloy always causes problems over time, I've been struggling all day in the workshop with some steel casters screwed in to an alloy frame and I've not skin on any knuckles anymore.

Like JR says, if you get them out copper grease the new ones to stop it seizing again.
 
I'd recommend soaking them in WD40 overnight for 4 or 5 days, to help the pentrating effect, before attempting to free them ....can't do any harm whatsoever
 
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