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gunny
When taking out the plug I can turn the plug about 1 or 2 turns then it starts to bind. I'm guessing I'm in for a head removal? Any suggestions?
cary
It does tighten all the way?
DBCooper
It could be some carbon in the threads near the chamber. There isn't much alternative to just working the carbon off, screwing the plug out till it binds, then in a half turn or so, then back out, trying to clean a little at a time. It might work, but that's best case. Worst case is that you already have stripped threads and your plug is now trying to cut some new threads in your head. How are the other plugs, similar, or is it just this one? If you have stripped threads again not much alternative, it's already happened, so you can just remove the plug the same way, out a bit, in some, then out again. If they're stripped you'll see aluminum in the threads once the plug's out, and you'll need a heli-coil installed in that plug hole. Don't try to tighten the plug and drive the car, the motor will just spit it out after a while.
gasman
Watching "Gosse's Garage" on motorweek...he said that to remove spark plugs on alluminum heads was to crack the plug (1/4 turn) start up the engine and rev engine to remove the carbon deposits on end of plug then slowly turn plug 1/4 turn at a time going back and forth to remove the plug.
Cap'n Krusty
That makes no sense at all. If the carbon got there from combustion, how's running the engine with the plug a little (VERY little) loose gonna get rid of the carbon?

The Cap'n
ttwitc9516
The threads won't have tension on them holding them in place so they will move back and forth slightly and ultimately collapse the deposits.
bandjoey
P e n e t r a t I n g o i l ?
Valy
Was that head overheating?
I hope is not something similar to the exhaust studs syndrome where the last aluminum threads detach and stick to the bolt.
Cap'n Krusty
QUOTE(bandjoey @ Nov 1 2012, 08:58 AM) *

P e n e t r a t I n g o i l ?


VERY difficult for the penetrant to get past the spark plug seal, you know, the washer under the plug .....................

The Cap'n
Cap'n Krusty
QUOTE(ttwitc9516 @ Nov 1 2012, 08:45 AM) *

The threads won't have tension on them holding them in place so they will move back and forth slightly and ultimately collapse the deposits.


I have my doubts regarding that theory.................................................................

The Cap'n
Elliot Cannon
QUOTE(Cap'n Krusty @ Nov 1 2012, 09:44 AM) *

QUOTE(ttwitc9516 @ Nov 1 2012, 08:45 AM) *

The threads won't have tension on them holding them in place so they will move back and forth slightly and ultimately collapse the deposits.


I have my doubts regarding that theory.................................................................

The Cap'n

So, are you going to enlighten everyone with a possible solution, according to your 75 years of experience or do you just log on here to let everyone know how their ideas suck? lol-2.gif
dian
i soaked the plug with a mixture of atf and acetone for a week, moving it twice a day and got it out in the end.
gunny
QUOTE(DBCooper @ Nov 1 2012, 05:03 AM) *

It could be some carbon in the threads near the chamber. There isn't much alternative to just working the carbon off, screwing the plug out till it binds, then in a half turn or so, then back out, trying to clean a little at a time. It might work, but that's best case. Worst case is that you already have stripped threads and your plug is now trying to cut some new threads in your head. How are the other plugs, similar, or is it just this one? If you have stripped threads again not much alternative, it's already happened, so you can just remove the plug the same way, out a bit, in some, then out again. If they're stripped you'll see aluminum in the threads once the plug's out, and you'll need a heli-coil installed in that plug hole. Don't try to tighten the plug and drive the car, the motor will just spit it out after a while.

all plugs come out normaly except #1.
#1 comes out about 2 turns then binds.
I can fully seat it after it binds.
Jon H.
QUOTE(Cap'n Krusty @ Nov 1 2012, 08:44 AM) *

QUOTE(ttwitc9516 @ Nov 1 2012, 08:45 AM) *

The threads won't have tension on them holding them in place so they will move back and forth slightly and ultimately collapse the deposits.


I have my doubts regarding that theory.................................................................

The Cap'n
From http://www.motorweek.org/features/goss_gar...rk_plug_removal
" You go down in there and you loosen the spark plug about one eighth of a turn. You do not try to remove it. Once you've done that to all of the spark plugs in the engine, you put the coils back on, and you start the engine, rev it hard, one time, shut the engine off, and then remove the spark plugs. Now what's all this about. Well, if you look at the bottom of a spark plug, you would normally see that there's carbon that has built up around the end of it. What you're doing by cracking them a little bit is that you're breaking that carbon loose, then when you start the engine it blows it out of the engine so that it doesn't get pulled up into the threads in the aluminum cylinder head."

New to me too.

Jon
Cap'n Krusty
QUOTE(Elliot Cannon @ Nov 1 2012, 10:12 AM) *

QUOTE(Cap'n Krusty @ Nov 1 2012, 09:44 AM) *

QUOTE(ttwitc9516 @ Nov 1 2012, 08:45 AM) *

The threads won't have tension on them holding them in place so they will move back and forth slightly and ultimately collapse the deposits.


I have my doubts regarding that theory.................................................................

The Cap'n

So, are you going to enlighten everyone with a possible solution, according to your 75 years of experience or do you just log on here to let everyone know how their ideas suck? lol-2.gif


Well, some say to always attempt removal cold, others say hot. I prefer hot. I prefer even more to prevent stuck plugs from ever happening. I use anti-sieze and the proper torque on every installation, and I replace plugs in 914s every 6K miles. I twist 'em in by hand until they're ready to torque, and I chase any threads that make hand tightening difficult. I have Helicoils (NOT Time-Serts) installed in the plug holes when I have the heads rebuilt.

In this situation, I would get the engine hot and VERY carefully work the plug back and forth, praying it'll come out without damaging the threads. If they're lightly damaged, I chase 'em. If they're trashed, I carefully install a Time-Sert.

The Cap'n
Tom
Cap'n Krusty,
Could you give us the proper torque figure for the plugs using anti-sieze? Haynes says 25 ft lbs, but I can find no where in the book where the torque figures given are for wet or dry threads.
Thanks,
Tom
LotusJoe
QUOTE(Cap'n Krusty @ Nov 1 2012, 10:42 AM) *

In this situation, I would get the engine hot and VERY carefully work the plug back and forth, praying it'll come out without damaging the threads. If they're lightly damaged, I chase 'em. If they're trashed, I carefully install a Time-Sert.

The Cap'n

agree.gif I've used time-serts for years. no need to pull the head. This is an easy fix once the plug is out.
Cap'n Krusty
QUOTE(Tom @ Nov 1 2012, 11:05 AM) *

Cap'n Krusty,
Could you give us the proper torque figure for the plugs using anti-sieze? Haynes says 25 ft lbs, but I can find no where in the book where the torque figures given are for wet or dry threads.
Thanks,
Tom


22.5 ft lbs. With anti-sieze, I go 25-26. Porsche never recommended anti-sieze back in the day, and the instructor at the school said it was because it changed the effective heat range. I don't see that, but I'm not an engineer ....................

The Cap'n
DBCooper
QUOTE(gunny @ Nov 1 2012, 10:33 AM) *

QUOTE(DBCooper @ Nov 1 2012, 05:03 AM) *

It could be some carbon in the threads near the chamber. There isn't much alternative to just working the carbon off, screwing the plug out till it binds, then in a half turn or so, then back out, trying to clean a little at a time. It might work, but that's best case. Worst case is that you already have stripped threads and your plug is now trying to cut some new threads in your head. How are the other plugs, similar, or is it just this one? If you have stripped threads again not much alternative, it's already happened, so you can just remove the plug the same way, out a bit, in some, then out again. If they're stripped you'll see aluminum in the threads once the plug's out, and you'll need a heli-coil installed in that plug hole. Don't try to tighten the plug and drive the car, the motor will just spit it out after a while.

all plugs come out normaly except #1.
#1 comes out about 2 turns then binds.
I can fully seat it after it binds.


If it comes out two turns then penetrating oil will get down the threads, so give it several squirts, give it a day to soak and try again. If no improvement, repeat a couple of times. If still no improvement, curse.
cary
QUOTE


22.5 ft lbs. With anti-sieze, I go 25-26. Porsche never recommended anti-sieze back in the day, and the instructor at the school said it was because it changed the effective heat range. I don't see that, but I'm not an engineer ....................

The Cap'n


I use anti-seize on mine. I just put a dab on one side. I don't coat the entire thread. Seems to be working for me. I like the new LockTite tube stuff. Just started my second tube.
As for torque. That's where I get paranoid. Don't get in a hurry. I make sure I'm getting them in straight first. I use the socket with an extension and my fingers to thread it in. Then I set the wrench for 22 ft lbs.

So far I haven't had any back out. But not putting on much anti-seize.
My .02c for this am.
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