Removing very stubborn spark plugs!

Discussion in 'Cars, Bikes 'n AFVs' started by Recce19, May 3, 2012.

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  1. OK, the problem:

    On a 1998 Opel (Vauxhall) Astra g, 1.6 litre, 8 valve, I cannot remove three of the four spark plugs, which seem to be stuck solid! I have no idea how long they've been in there and no idea what idiot put them in so tight! The fourth one was removed end of last year, by a mechanic who was not happy about the possibility of snapping it!

    What I need, is your help in getting them out, without (a) breaking them and (b) stripping the engine down!

    So any suggestions will be greatly received! :grin:
  2. Shit load of penetrating oil, keep applying, leave overnight? Will the engine run? Get it hot and try then.
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  3. Cheers for that! Will give it a go and yes, the engine runs!
  4. Make sure the spanner fits properly and keep it straight. Before loosening, try tightening very slightly which does help to free the plug. If you snap the plug you're in for some expensive repairs.
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  5. TheIronDuke

    TheIronDuke LE Book Reviewer

    I am so not offering advice here since Hoppy is a better mechanic than me. Hard to imagine, but it is true.

    What he said. Soak the bastard in as thin an oil as you can lay hands on. If you cannot heat the engine I would warm the oil? Every now and then I would put a drift onto something solid, like the bit of the block next to the plug, and bray it sharp with a heavy hammer. Just to loosen things up.

    I'd give that a week and if it was not working? Jack up the number plates, slide the car out. Slide a stolen car in. Let down the number plates.
    • Like Like x 1
  6. Patience. Heat. A socket that a. fits, and b. isn't made of cheap monkey-metal, and as long an extension on your ratchet-handle as you can get away with to increase your moment-arm.
  7. Sometimes the old ways are best!
    go and get a can of plus-gas penetrating oil..forget wd40 and such pish it's only fish oil.put plenty of plus-gas around the plug seating leave overnight and hey presto they will jump out in the morning.
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  8. Take the car for good thrash to get it very warm, then with a good quality plug socket try and loosen them. If they don’t loosen then try using an air wrench. Sounds a bit brutal but it usually does the job.
  9. Yep, get 'proper' penetrating oil. If you're still driving chuffers, see if one of the mechs will lend you a big **** off torque wrench, you can apply a lot of force gently. As Donmac said, tighten slightly then untighten.

    And yes plenty of patience.
  10. Don't forget to tap it gently using something as a barrier such as a piece of wood.
  11. It's not fish oil but I agree I think plus-gas is superior if it's still made.
  12. If all else fails, try hitting the top of the plug with a drift; the shock may break the corrosive seal on the plug/head. Be warned, it will doubtless bugger the plug!

    Patience, plusgas and a big breaker bar are your friends!

    It is possible to rethread a plug in situ, should it all go Peter Tong. Not desirable, but cheaper than taking the head off
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  13. Lubricant, then an impact driver with socket.... gentle taps ?
  14. Lots of good ideas and advice, so thanks for that!!...Oh and Leveller, I have new plugs to go in, so not bothered about buggering the old ones up - just need them out!
  15. I'm shocked, not one tiffy on to help out.
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