Stuck spark plug

The plug in my No. 2 cylinder will not back out. I am trying to replace it. It is very easy to back out at the start, then binds up. Any ideas as to why (carbon deposit?) or how to remove it without destroying the aluminum threads in the head?

Happy new year

Paul

maybe squirt a few oz. of light oil in there, let it soak, and try backing it out a little at a time, maybe marvel mystery oil.

pb blaster?

you know for certain it was not cross threaded going in?

If it's a plug that reached into the chamber too far, as in threaded part extended past the threads in the head, then carbon may well be your culprit.

A full soaking through the intake port might help but I think you're gonna' have to just wet it up as best you can by running Liquid Wrench or the like down the plug from the wrench side and then going for broke.

Make sure your wrench (socket) fits tight and keep it straight. Be ready for the idea of a Helicoil fix after the plug is out. Alloy heads don't like it when threaded parts go in or out hard - you'll probably lose the threads if you haven't already.

The little kits that come with a threading tool and heli-coil driver aren't too hard to use and once the hole has steel threads it shouldn't give any more trouble if done right. They come with directions.

Millions of prior VW owners have paved your path - this is oldtime VW stuff.

The engine expands when hot . . . a lot. You may have an easier time if the engine is up to temp. To soften the carbon built up on the plugs and on the valve heads, mist/spray windshield washer fluid (cold temperature formula) down the carb(s) as the engine is running up to temp. Works wonders.

This is SO old skool, it's pre-skool.

Luck,

TC

TC's method works......Really!

But if it doesn't in your case, (how many miles are on that engine, anyway??) try backing it out til it binds, then turn it IN 1/4 turn, then soak the bottom of the plug with PB Blaster to really wet the threads. Go away overnight, then try slowly turning it out. It might take a couple of tries, but it should loosen by going out 1/4 turn at a time, turning back in 1/4 turn each time.

After you get it out, measure the depth of the threads, then measure the thickness of the head where the plug goes through. Your plug may be too deep. Also, when you install new plugs, always put a dab of anti-seize on the threads.

DO NOT put anti-sieze on any sparkplug threads! I am a professional mechanic by trade,and this is common knowledge since the plugs need a good ground to fire well. Anti sieze can be a insulator on the threads. Just tighten enough to squeeze the crush washer,usually 1/8-1/4 turn after the threads bottom out andf you will be good.

Good point.

Shoulda thought of that!

Also with the engine up to temp back it out until it stops and then tighten it back in a little. Repeat this process backing it out a LITTLE more each time. That's what we do on aircraft engines if required. Also John at Aircooled recommends using 'Milk of Magnesia' for the threads when installing plugs.

I re-thought this,and wondered if "copper-paste" anti-sieze would be OK. I have never tried it personally,but was always cautioned not to use anything on sparkplug threads.

I've used anti-sieze on every plug for 45 plus years.

I've used "Never Seize" for over 50 years.... It will take temps in excess of 1000 deg F. because it has nickle as the working agent..... Nickle is a great conductor of electricty and heat..... It takes only a small amount to do the job.... A match heads worth would do a long reach plug with some left over.... I've only lost one plug, when the previously installed helicoil blew out.... My .02.

Just remember, before you do ANY work on your car concerning the use of anti-sieze compound, get out the tube and apply a thorough coat all over your hands and the sleeves of your shirt (maybe across your belly, on your baseball cap and along the side of your jeans, too).

You might as well get it over with right off, since it'll get all over you anyway.

8>(

True Gordon...So true.... A smidge goes all over the place.... ;- )

Gordon, been there, done that :)

GN you forgot to cut off the end of the tube, lay it on the floor and smash it with a work boot, then lay down on the floor and roll across the mess...Optional is to track it into the house too~

When you roll across it, extra points if you get it into your hair...

I use never-seize on all plugs - but just a smidgen. You can definately short them if you get alot on them. I've done it and can verify that they will DEFINATELY not fire...

If it's been done wrong, at some point, I've probably done it...

Smidgen - good. Glop - bad.

angela

Great point on the grounding of the spark plugs; if you don't tighten them snuggly for fear of stripping the threads you run the risk of them not making good ground and eventually dying and your car will backfire like crazy and feel like it's running on two cylinders. I speak from experience.

Or they can back out of the hole and you have the chitty chitty bang bang sound.

Go ahead and get a tap and a heila coil sized. then can at least fix it at that time if it still monkeys up.

Two drops of Oil of Wintegreen into 1/2 oz of kerosene will cause even the most stubborn rusty nuts to give up. Do not inhale...purple haze...put a spell on me.....

David, save that recipe for Carlisle.

Paul,
Any luck getting that plug out yet?