Seized spark plugs

[911pcars]

I'll leave the discussion on contraction and expansion of materials to those who want to look up the physics.

The opinions offered in this thread are anecdotal and may or may not reflect real world circumstances. It wouldn't be out of the ordinary for owners to neglect changing spark plugs (or other maintenance items) for many thousands of miles past due. The longer neglected, the better chance of electrolysis taking place between the steel spark plug shell and the aluminum head; the higher odds of carbon buildup inside the combustion chamber.

In addition, not sure how many car owners perform their own service. If you do, great - you have taken the responsibility. However, if someone else performs those procedure, one could assume it was done to specs. As for spark plug R&R, my guess is maybe <20% of repair shops use a torque wrench to tighten spark plugs, with or without anti-seize (which also, btw, minimizes electrolysis). And we won't talk about the percentage who overtighten the plugs, with or without anti-seize.

Sherwood

[TCracingCA]

That wraps it up!

OOPS! PS almost forgot the smile thing!

[Bob Kontak]

Originally Posted by TCracingCA

That wraps it up!

Wraps what up?

[E Sully]

Hopefuly it is wrapped up when Kamalea gets his spark plugs out. I have read that using the Porsche supplied wrench from the tool kit makes it easier than trying a socket on a ratchet. It is very tight working in the engine bay of an '86 930 Turbo.

[Bob Kontak]

Originally Posted by TCracingCA

OOPS! PS almost forgot the smile thing!

I bet you are but a flash in the pan.

Gone within a couple months because you will get yourself, and your bull f***ing s*** 325 HP "R" smacked around so hard you will tire of the push back.

Mark my words, Slick.

[TCracingCA]

And I give to Charities, find lost puppy's new homes, help old ladies cross the street, give food to the homeless, and you turned down my friend request! And yes I am noticing that you are one of the Posting Kings! Don' worry, you can keep the crown, and I will add a few more titles-- Baron of Knowledge, Judge Porsche, Crown Prince of Typing, etc.!

I thought you would be happy I was done. I am sure some felt I had contributed some good to the conversation! But yes the success of getting them out would be great to hear, I really thought I would look in and see if that happened or whether he had to take it somewhere or pull the head!

I won't insult you back or your car!

PS maybe the Smiles offered being limited are hurting my sincerity!

For the thread, if the spark plugs are removed with a plan to reinstall, then at that point a decision has to be made to put on an anit-seize or not back on. I think, but others would have to answer as to whether new plugs have some treatment done for this purpose. I think they do!

[Bob Kontak]

Originally Posted by TCracingCA

PS maybe the Smiles offered being limited are hurting my sincerity!

Take a course in common sense. You have something to add. Focus on that slice of value for the time being.

Here's a hint - never, ever attack someone without calling them a name. If you are going to be a mamby-pamby, it will wear on the members.

Attack, with extreme prejudice. Never beat around the bush.

[TCracingCA]

Something, I will still try to get something relevent in about the thread.

This type of thing or a broke off bolt head and such are some of the most frustrating mechanic issues to deal with. Thus I am not looking to come up on the general consensus as to what camp has 51% or higher. I will often take in information and form my own plan of attack to a problem. Thus what the OP should do. There were in this thread and on the forum a lot of smart guys! Heck, somehow they raised enough money to buy Porsches!

Your first line statement is respected.

If I have a difference of opinion or a situation where I am not typing on a forum that is supposed to be for fun and informative (and people should have thick skins doing so), I would rather be face to face and man to man! Therefore nothing you said makes me hate you or even makes me dislike you!

Yes, as I tear back into the projects, I will tend to go back to my cave and play in my world of toys!

PS because I am starting some heavy duty and extremely costly builds of Porsches, I am brushing up on my knowledge and gaining assistance from reading other threads and such while I interact and throw in on a few threads (but I am far from being a rookie at building Porsches)! Thus getting closer to having specs and ideas on build! Researched 11x15's today and Backspacing of around 120mm, so I can work out things, cutting battery boxes out of front of car, just because I don't like them there! And other things! Thus my stay will be short term here!

PS I will even announce it if you request it, so the Moderators and Self Appointed Moderators and such can all feel more relaxed!!!

[Bob Kontak]

TCracingCA

This is not the first thread where you have taken heat.

Topics are not relevant. However, you can spend a good deal of time explaining yourself after you have made a post that rubs people the wrong way.

Why not put some of that effort in up front?

[Flat Six]

Thus my troll meter and BS detector are both redlined . . . .

[irobertson]

Originally Posted by TCracingCA

Yes aluminum will expand and seize the plug also harder than it is! ""Thus"" why do people think that the aluminum head is going to expand with heat everywhere except where it holds the spark plug threaded in???? OH Boy! ?????

As we all know, heat expansion causes things to grow. Both the outer dimensions and inner dimensions grow, meaning the holes get bigger too. It is not the case that the outside grows while the inside contracts as you suggest. If that were the case, we would have a whole host of other problems, like cams and cranks binding up in our engine cases because the clearances shrunk as things got hot. Take for example the practice of heating sleeves and gears when installing them onto the main shaft of a transmission. Heat it up, slip it on, and as soon as it cools, you need a puller to get it off again. Same physics hold true for spark plug holes, they get bigger when hot.

As for the OP's topic, I would hit these with a 50/50 mixture of ATF & Acetone, heat cycle the thing (go for a drive) then hit them again and let them soak. (repeat as necessary) These are not small bolts. Probably the largest thread surface of anything else on the motor with the exception of possibly the head studs.

[911pcars]

Originally Posted by irobertson

As we all know, heat expansion causes things to grow. Both the outer dimensions and inner dimensions grow, meaning the holes get bigger too. It is not the case that the outside grows while the inside contracts as you suggest. If that were the case, we would have a whole host of other problems, like cams and cranks binding up in our engine cases because the clearances shrunk as things got hot. Take for example the practice of heating sleeves and gears when installing them onto the main shaft of a transmission. Heat it up, slip it on, and as soon as it cools, you need a puller to get it off again. Same physics hold true for spark plug holes, they get bigger when hot.

As for the OP's topic, I would hit these with a 50/50 mixture of ATF & Acetone, heat cycle the thing (go for a drive) then hit them again and let them soak. (repeat as necessary) These are not small bolts. Probably the largest thread surface of anything else on the motor with the exception of possibly the head studs.

FWIW, while the thread pitch is different, the typical spark plug thread (14mm) is the same ID as our lug nuts.

Sherwood

[TCracingCA]

So when someone is done and said everything that they were planning to say, is it classy to keep pounding away by quoting them-- low class! If you have something different to add, the classy thing to do is just add you wisdom. You must have a real complex if you have to prove a particular individual wrong, instead of just trying to prove a theory or method incorrect or improper!!!!!!!!

Ok, Manufacturers Chevrolet, Ford, Subaru etc.etc.etc. etc. (almost all of them) say to not change them in aluminum when cold soaked (meaning freezing), or Hot (meaning hot). Generally that leave you at room temperature and warm! If it is stuck, then you fall outside of just generally changing them, and they don't have instructions in your manual on that, but some heat expansion/contraction could be of benefit, but for the removal (room temp or warm is this the range) for extraction!

I never in this thread commented on hole diameter (bigger or smaller)!!!!!! Learn to READ!!!!!! Because that area is very reinforced, and circular, it will tend to keep it's shape, but the effect on the expansion happens with the threads in relationship to the plug threads!!!!!!! Thus stripped threads-- get it now???

In the machining process, they are using tools of certain diameters to cut those threads (male on the plug), female on the head! Thus true the tap or die can get warm/hot in that process (the drill or cutter prior to the tap or die definitely so, but the tap and die less affected)-- probably one of the reasons some engines are good and some are bad! But ideally you are cutting those without expansion. Thus to marry fit together the best relationship to each other would be room temperature through warm!

[911pcars]

Review this link that contains additional comments on removing stuck spark plugs:

OT: dry ice to remove spark plug in Al head

Per my comments earlier about using a coolant on the spark plug to contract its dimensions, here's a related suggestion in post #18:

<<
Lycoming, who has been making aluminum heads for around 80 years, says to remove a stuck spark plug:
1) Warm engine.
2) Use an inverted funnel - small side around the spark plug - aim a co2 fire extinguisher at the plug. The inverted funnel keeps the co2 off the head itself.
3) Let fly the co2!
4) Unscrew plug.

Since I always used the Champion graphite based spark plug never seize I didn't have to try this .
>>

In addition to a CO2 extinguisher, can also use A/C refrigerant and liquid propellants in compressed air dusters (Diflouroethane). When released, the liquid Diflouroethane has a temperature of approx. -13º F (-25º C). Just One Point Of View [justonepov.com]: Paintless Dent Repair Using a Heat Gun and a Can of Compressed Gas Duster

Use with one of the penetrating oils I suggested way back in post #5.

Sherwood

[Draden]

The FAA has guidance on this in the form of what is called advisory circulars.

(Note many mooney aircraft were built with Porsche engines and most 6 cylinder reciprocating aircraft engines are the opposing 6 type. Lycoming and continental.)

When it comes to cars. There's a lot of old wives tales but in the aviation industry. There are set rules so damage and death does not occur to to improper maintenance techniques.


TC Racing is correct. Removing a plug should always be done ONLY after the engine has cooled

Remember that dissimilar metal is a key factor here and most everything is designed to be assembled and disassembled at room temperature to avoid seizing issues between dissimilar metals.

The head are aluminum ( love to hear my British friend pronounce that word!)
Anyone who has had to remove a cylinder head to retrieve a broken spark plug knows how important it is to use care in spark plug installation and removal.

Lets cover some of the most common plug installation issues and how to avoid some common pitfalls.

Over-tightening spark plugs or improperly cleaning the threads in the cylinder head before installation of the NEW spark plug is a very common issue that can cause thread damage. Overlooking these basics can lead to breakage issues during the next replacement.

Another issue is thread galling in aluminum cylinder heads. Galling or binding between the plug and head can destroy the thread and possibly result in plug breakage. To avoid this, it is important to let the engine cool down before trying to remove a spark plug.

Installation recommendations vary by spark plug design; however always be sure there is no carbon or other contamination in the cylinder head threads prior to installation. There are special taps available designed to “clean” the threads and remove residual carbon if necessary. Also, be sure the threads on the spark plug are undamaged. Never consider installing a spark plug – even one that’s brand new – that has been dropped. Generally spark plugs come pre-gapped from the factory, however it is critical to always verify the spark plug gap meets the manufacturer’s recommendation for the application you are working on before installing a spark plug into an engine.

Tapered-seat spark plugs should be installed by hand until finger-tight. Then use an additional 1/16th turn applied with a spark plug wrench to ensure the spark plug has been tightened to the manufacturer’s recommendation for a 14mm thread. Alternatively, using a torque wrench, tighten the spark plug to approximately 7 to 15 lb. ft. for 14mm threads and 15 to 20 lb. ft. for 18mm threads to ensure a gastight seal. Overtightening a spark plug will stretch the plug body and potentially result in breakage upon removal.

For gasket-type plugs, install the plug until finger-tight. Then if the plug is being installed with a new gasket, use a spark plug wrench to apply a 3/8 to 5/8 turn – depending on head material. When reinstalling a used spark plug with a used gasket, only ¼ turn is necessary, regardless of head material.

It’s not unusual to have difficulty removing a used spark plug. Be sure to allow the engine to cool before attempting the job, and always be sure to clean away all debris around the plug prior to removal or use compressed air to prevent entry into the engine. If the plug appears to be overly tight and/or there is corrosion surrounding its base, it is acceptable to apply a quantity of penetrating oil (rust breaker). After allowing the penetrant to do its job (most require at least 5 minutes), apply steady pressure with a spark plug wrench until the spark plug loosens. Do not yank on the wrench, as this could cause breakage.

For especially difficult to remove plugs, try loosening ¼ turn, then retightening. Repeat this process while reapplying penetrating oil until the plug is removed.

It’s always a good idea to use a thread chaser tool to remove carbon and other contaminants from the threads in the head before installing a new spark plug.


I generally use FAA ac 43.13 aircraft standards on my car after being exposed to these rules for the last 30 yrs of my life. They cover everything from thread protrusion to welding techniques to wire installation to you name it.

An airworthy car is a safe car.

[Draden]

I run the Flight Test center for a major biz jet company and ther is a standing rule in the hanger. If you get caught removing any screw with a screw gun. Your fired because dissimilar metal will seize when the heat from friction is generated by speed. So definitely don't heat anything purposely that is threaded and dissimilar. Many times have the titanium floorboard screw been attempted to be removed by using a screw gun and they almost always seize into the aluminum nut plate after a few turns at speed.

Note. Aluminum does expand quicker than the steel plug. But come on guys, expansion is in all directions. Unless you have trained aluminum molecules

The head hole will get tighter with heat. You'll seize for sure. Physics 101

Room temperature and turn slowly by hand with any machined screw thread


Looks like there are a few headed heads on this forum. Some people need to relax

[TCracingCA]

Originally Posted by Bob Kontak

If there is a difference in opinion, sure.

This is what I think:

I think you have a 240hp car, not 325, assuming you have a 911.

I think you have an ego the size of the Queen Mary with nothing to back it up.

I think you have zero formal education.

I think you were harshly potty trained.

Now, where does that leave us, Professor Classy?

Reply!

Guys like you will get someones topic moved to Off-Topic!

First yes if you can do something that can expand something (the Head), while contracting something else (the spark plug), then that can work. No where in this thread have I had to comment on that, because that good advice was well covered! My focus was purely on taking a wrench on a hot engine and my feelings about what would happen to the threads maybe!!! I have not in this thread disputed or commented on heating to the head vice cooling the plug! If it is that stuck, then I am sure the threads will take some further damage in the process, but short of taking the head off and drilling out the spark plug, maybe the only way. Also alot of chemicals suggested here, and I would be willing to try some of those great suggestions!

And maybe to clear up the confusion where people are split 50/50, it takes someone like me to reply!

Ok now for your post!

Someone with probably one of the crappiest made 911's (that Vintage 1981 SC) really gives me an impression of where you fit in! Don't need to qualify our cars to you! I learned that street racing and talking up your own engine is not acceptable or it has been decided not acceptable by who? That it isn't well received on the forum?? OK (wrote nothing about anything I owned into this thread, so why are you bring things in from another thread that got locked, and another moved Off-topic? I would call that inappropriate toward me! Thus you keep bringin that back in?? I guess my asking the Moderator to lock the thread, didn't give you the chance to disrespect me more??? No reply needed!

Since you brought it into this thread and the Moderators didn't check that! I will comment about the car I referenced for a power to weight against another car with a respectful power to weight ratio, but we basically have a full Race 911 Engine in a street car and all of the race suspension hardware, etc.. There is nothing stock about it! Thus you must not be aware that the case and heads, cams available for 911's can obtain those levels. Therefore I would suggest you attend a PCA track weekend or you can go read some books about it! My opinion, someone with experience can easily build to the same level! But most would probably have complications tuning for those levels. But building sure! Not many people put full tilt racing engines in their street cars, but it has been real popular at the shows!

Two are you an ex-teacher?-- do you red pen the posts and check them for grammar! I don't think I need to write a reply in a car forum that would satisfy your literary standard! I didn't think the Forum was requiring educational diplomas (I have two College Degrees!-- Electronics, Real Estate-- ex-Military Electronics Technician Navy, so true I did not chose to be an English Major or Minor!

Ya, I have an ego as others here seem to have (fully respect all of them)-- I do really good in life! I have some nice cars. Do others have better cars, I am sure others have better cars and faster cars!

Thus if the Moderators are really on top of this Forum (me being relatively new to Pelican), they should go back and clear any insulting commit said, ban anyone directly insulting and that has not been me! Oh yes, I did insult your car!

[Draden]

The guy lives in Ohio and drives an early 80s SC and a targa at that. He has a lot to be bitter about. Don't sweat it man. He was rude. But maybe his dog died or he owns a new vw beetle that is just as fast as his SC

Offer advice that's ok, but he slammed a fellow pelican because he differs in opinion. He needs to go enjoy the ohio regional forum. What exactly is engineered by him in his car that wasn't bought and bolted on? That's right. Consider the source and his vehicle.

TC. Thumbs up man. You've got beautiful cars. That engine, yea, after riding in it with you, I'd say every bit of 325hp

[TCracingCA]

I still think the threads will take damage if it isn't sufficient to really shrink the plug! I don't know! And the more I think about it, the heads will still take damage even in this progress period! (maybe minimally, but some damage). This type of thought works for other stuff, but don't think I would want to mess with my expensive parts in this way!!!!!!

I would """"THUS"""" say, do this at your own RISK!

Therefore if the solvents at room temperature or slightly warm doesn't get it, take the Heads off!

PS I like Targas alot in general, but not that year SC! But I am open to someone changing my opinion, because I generally like most Porsches (except for the 924)! The SC was marketed to be a world car, the everyday mans car for the masses! Whereas Porsche prior was jumping from innovation to innovation previous to this model. It was down on power and overweight, but still had nice wheel arches and mostly Carrera parts, but the pumps ended up in the trash or as wall art in garages. Performance was down, because it was tuned to run from low rpms and for a 3.0 Liter was making only 180hp only! Unfortunately Porsches quality control suffered during this era and the Targas leaked! With the smog laws and such, it hurt alot of Manufacturers!

[Wayne 962]

A few things:

- The rhetoric in this thread is not compatible with the culture of this forum. Change or there will be changes.

- As I wrote in each of my books, Porsche does not recommend using anti-seize on any of the plugs. This is documented in Porsche Technical Bulletin 9102, Group 2 identifier 2870. The bulletin applies retroactively to all models, and the theory is that the anti-seize tends to act as an electrical insulator between the plug and the cylinder head. This could have a detrimental effect on the firing of the spark due to the loss of a good, consistent ground connection.

- There is a bit of a trick that I have sometimes used to remove stuck bolts. I heat the outside up (like the cylinder head), and then use liquid nitrogen or something similar to drip on and cool the center plug / bolt that is to be removed. This heats up and expands the outside, while cooling the inside. You can take a can of compressed air (the ones used for blowing out computer equipment), and turn it upside down, and liquid-nitrogen-like coolant will drip out. This is pretty useful for this purpose.

-Wayne