How long should I run stuck#1 plug?

[dshepp806]

Greetings to all...

I posted this fear & loathing tribulation months back...discovery of a stuck (crossed) #1 spark plug....bought my 89 3.2L in Nov/06. Later, during complete tune up,..I felt the #1 plug WAYYY too tight for this "enthusiastic owner"'s wrist and had the Porsche shop look in to it while she was up for some minor work/tires, brakes, etc. Turns out that none of these fellows (2 German P-wrenches plus the owner) could get this plug out,..appeared to be crossed by P.O. (wrench?) Bottom line: engine drop to repair this,..... I made damned sure I bought PLENTY of beer for all those P-wrenches who engaged my nightmare,...so frikin thankful that NO ONE snapped it...INSTANT RESPECT!!! Advised (and decided) go many more thousands of miles before addressing this issue with #1. Begin budgeting for the upcoming (all of it). My situation/concern is this:

The history on this car shows this plug to be changed out 103KMiles....I bought it at 113KMiles. I changed the plugs at @ 118KMiles (minus #1, of course..) ,..as well as new Beru ignition set, dist cap and rotor. I change my cap, rotor and plugs somewhat frequently, loving the thought of pure copper......She runs perfectly,..each new pathing of copper yields a bit of improvement. I don't even give it time to come close to laying down carban traces....

#1 situation drove me nuts...many on this forum consulted with "DRIVE IT,DEAL WITH IT LATER...even sharing some similar experiences. She's now at 130Kmiles,..running tops, with stock chip...really, really smooth, as to fuel and fire......

Question:

am I impacting the #1 cylinder (and any associated components) in any "negative way" by prolonging this repair (subsequent installation of fresh plug) for #1's fire?

When I attempted removal, I surely got no more than 1/4 turn MAX....and promptly attempted reseating,..acquiring only 1/4 heading home...(freaked me out..) After getting it back from the shop (after their attempt...) it seems as though the boot is a bit higher than before....connector's well seated on the plug...just concerned about how far "in" the plug presently IS......otherwise,.,.


Should I react a bit more quickly to this situation? Would you?

Best,

[Early_S_Man]

Doyle,

DME engines with a properly functioning O2 sensor, wires, cap, and rotor ... can easily put 50K miles on a set of spark plugs with no significant, visible deterioration, that is, no fouling or deposits that are degrading the spark or impacting fuel mileage! A traditional ignition scope such as a Sun or Delco analyzer can tell you when the plug is losing spark Voltage or mis-firing.

Eventually, I believe the head will have to come off, and Heli-Coil or Time-Sert repair will be needed.

[charlesbahn]

I had a stuck plug. Sprayed it with PB blaster about once a week and kept driving it, and each time tried to gradually turn it without too much torque. Each time it turned a little more. Finally got it out, threads in the cylinder head were OK! It was a very old plug and I guess the PO had the same problem and just left it when the others were changed. Put new plug with oil on the threads and all was OK. Now I change the plugs once a year just to lubricate the threads.

Good luck.

[Shoepop]

I would try the PB and the little @ a time approach. If it's that tight there is pleny of metal left to work with. After you get it removed use a KD tool # 3545 14MM INTERNAL spark plug rethreading tool. It threads from inside out. The inside of the SP hole is tapered it and will not be damaged if plug is cross threaded, the tool will catch the good threads very easily and will rethread on the way out. Been there done that W/O removing engine. Put a bit of grease on the tool to pick up any chips. Now I always use a piece of hose over the plug end to start the plug when installing. With the hose if it feels like it's not starting well it's not.

[Mo_Gearhead]

QUOTE: "Now I always use a piece of hose over the plug end to start the plug when installing. With the hose if it feels like it's not starting well it's not."
_____________________

This is a great, age old trick for installing spark plugs on engines that have recessed plugs (IE Porsche) and where vision is impared, you need to 'feel'. EVERY ONE of you should be using it.

If you are sticking the spark plug in a socket and just stabbing it down into the head BEWARE! There is no 'feel' with a socket. Steel plug vs aluminum head= potential crossthreading.

And always change your plugs with the engine COLD.

[Early_S_Man]

Mo,

I disagree strongly with both of your recommendations!

The best tool for installing spark plugs in a 911 engine is the early, non-pivoting Klein 21 tool!!! There is no way a piece of hose can have dimensional stability of that precise, knurled grab handle precisely sized and spaced for the human hand to do the job right the first time, and for decades ... time after time!

An aluminum head expands at a greater rate than a steel spark plug, so a warm head lessens the the tendency for the spark plug to bring out part of the threads from the head than when removing from a cold head where the aluminum has shrunk down and tightened around the spark plug as it cooled! A really bad situation if the spark plug was installed without anti-seize compound that Porsche now recommends!

[charlesbahn]

I second the use of the factory spark plug tool. It's the only way to R/R the plugs on these engines.

[Gunter]

The plug may be seized, not cross-threaded.
Use repeated squirts of penetrating oil like PB Blaster on a slightly warm engine.
Try moving the plug both cw and ccw.
Repeat this procedure for several days.
If that doesn't work, drive it for another ~20k
Before you take the engine out, use a 1/2" drive (Not 3/8") long socket (13/16"?) with a breaker bar, lots of PB, and break it loose.
You might win but, if not, you want to remove the engine anyway.
That way, you'll get another ~20k.

[sammyg2]

Kroil works pretty darned good too. I've never found anything that works better or faster and I've prolly used a couple of 55 gallon drums of it over the years.

[rs dreamer]

Warren, What is Porsche now recommending regarding anti-seize for spark plugs? Is it a specific type or brand? Thanks, Gary

[Early_S_Man]

Gary,

Lubro Moly Assembly Lube

[dshepp806]

Early_S_man: Thanx for the response. Good answer, in terms of how she's firing...I'll have it put on an analyzer to look at the waveform...at least for a piece of mind..she's running so well...I've not used the rubber tube approach but have read of this MANY times.....I seem to know what's up on the threads with the Klein tool....(as stated: this #1 was put in place by someone else.....

As Gunter mentioned about seizing vs. crossthreading.......it's hard for me to think that the shop that maintained this baby for 7 years (did the top/bottom rebuild) crossthreaded the damned plug.....it probably IS seized.....

Trust me....we doused this ***** over several days with ALL penetrants,...then (as stated), she was handed off to the REAL P-wrenches. I don't think anyone use ANY breaker bars EVER...

We tried it all.........time for a time-sert..The "last step" mentioned by Gunter sounds completely logical, knowing you've prepped for engine drop...nothing to lose at this point....

I do have the tool that shoepop mentions....guess I'll wait and see what the analyzer shows me.......what a pisser.......AGAIN,..she's running like a raped ape and I'll not toy with such a great running condition! ONLY if there exists some conditions (due to this seemingly permanent plug) that would not make the PC's, valves, or fuel injectors happy.....worse yet imparting excessive carbon buildup, or whatever....THAT"S what I'm interested in knowing...

As to antiseize,....I've not used this in my plug changeouts...I've followed Pete Z's recc's on using Lithium based stuff....he's right,..they come RIGHT OUT.....used minimally...at the proper spot...so far: works great...

Always careful on the torques on the plugs, as well.......it's just that I've only been able to change out 5 at a time!!!!!!!!!!!

Thanks to all of you guys....

My best,

[Mo_Gearhead]

Warren:
I have never seen/owned a Klein 21 tool? But I have used a piece of hose on ANY spark plug that I could not start easily by hand, for over 40 years. Never had one cross-thread.

We will agree to disagree on the other also. I would never remove a spark plug from a hot aluminum head.

EDIT: I am assuming that, for most purposes here, we are discussing people working on their cars at home (not at the track/tuning sessions). There may be occasions where one NEEDS to change a plug in a hot engine. But otherwise ...I do mine cold. J.M.O.

Carry on.

[dshepp806]

I've never engaged a plug changeout on a hot engine either...always,..cold.

Best

[Walko]

If the plug is seized leave it soak for a week with some type of penetrating oil and attempt to move it. if the motor has to come out then your may as well pull the heads off and fix the issue.

Michael

[Joe Bob]

Kroil or PB Blaster......or OFF WITH IT"s HEAD!!!!

[88911coupe]

Just to clarify...what is "warm" with regard to the cylinder heads? I thought I'd read removing plugs on a warm engine is not recomended however Warren's logic about the expanding aluminum makes sense...as usual.
I do use anti seize but it's just the standard stuff you get at Pep Boys and Autozone...am I risking breaking off threads or a stuck plug?
TIA

[burgermeister]

From my Beetle days, Bosch plugs were least likely to seize, and all books & articles I read seemed to agree on that point - no idea why. I always used copper-looking antiseize, standard auto parts store stuff, and I never had any issues. Doing the same on the 911. PO seems to have used similar looking anti-seize, and plugs came out fine after 40K miles. Haven't had to R&R the new ones yet.

[Gunter]

LOL, use common sense.
Yes, plugs are changed normally with engine cold.
This is not a normal situation, that's why the recommendation to try this ONE plug with a warm engine because ALU expands a little more than the steel plug.
LOL

Originally Posted by dshepp806

I've never engaged a plug changeout on a hot engine either...always,..cold.

Best

[Superman]

Another thing I'd probably do is to LOOK at the plug. Use a mirror if necessary. Look carefully to see if the tip of the plug seems to be centered within the cavity. If it is cross-threaded, you should be able to tell. If it is dead-center, then I'd conclude it is not cross-threaded. This is important. It means that if you can get the plug out, there is no need to worry about machining the head.

It is not unusual for a spark plug to get a carbon ring built up on the threads that face the combustion chamber. FWIW.

I agree that if the engine is running great, there is no need to fret at this time.

I also would probably bathe it in Maltby's or PB Blaster or something, over time, and continue to work it. Ultimately, if the plug starts to misfire or you decide it IS TIME to get the plug out regardless of consequences, then okay. I'd work it as slowly as possible using copious quantities of penetrant. Engine warm. Or maybe forget the penetrant and get the engine HOT. At any rate, a spark plug is not going to be a match for a breaker bar. It WILL come out.