Ritzy4Runner

iTrader: (1)

Well I may have gone and done it, I broke out the FSM and decided I would help my daughter tune up her truck, replaced the wires, cap and rotor. The rotor was toasted, cap looked pretty rough too so those were good calls. The wires were 2001 vintage and rated out at 5.5K ohms but replaced them anyway.

The truck had started to cool down enough so I could get my hands in there without burnig so I pulled #6 sparkplug to check it and regap. I have done the same on my 98 and it came out pretty much normally. The gap was around 35 and the FSM calls out 31, regapped and installed. Tried to pull plug #4 (middle plug) and got it about 3/4 turn and it started to get real tight. Went about another 1/8 turn and it was way to hard for the plug to be normal. Tried to go back in and it didn't want to move ... I am so worried now.

I started checking and some postins say something about anti-seize? Did not see that anywhere in the FSM. Also one guy mentioned (yeah now after the fact) do this when the engine is cold, GREAT! Anyway, I decided not to mess with it anymore. Put it back together and it fired right up but I still have a very bad feeling about #4. Any suggestions? I really can not afford and either can my daughter to have to put this truck up on blocks and do a head rebuild/replacement. Was hoping this would take care of the rough idle issue which as she told me further, is random, will do it either warm or cold sometime it runs just fine at idle others it doesn't. Normal running at speed is not an issue. (sigh)

bugs1961

I have seen spark plugs seize in aluminum heads before and it isn't pretty. The threads will be pretty much gone, but they can be repaired. NAPA and other parts stores sell spark plug thread repair taps that may restore the threads enough to be usable again. If not, then Helicoil may be your best bet. The number 4 is pretty accessible and you may be able to do with the head installed. That plug will probably keep firing until it's shot, but you will eventually have to get it out and repair the threads. Good luck.

Ritzy4Runner

iTrader: (1)

Will I be better able to remove the plug when the engine is totally cold? Would using penetrating oil help? Still looking for a way out of this thanks for the tip on the repair tabs

Ron Helmuth

Ritz we just had this happen on the MR2 and my suggestion is to put the spark plug boot back on and let the engine run to warm up. Remove the spark plug while it is very warm.

Not sure if penetrant oil is a good idea or not.. try my method first

For us that did the trick-now yes it was a pain to remove it while hot, but the threads had unseized enough to let us do it. Do not force it and crack the plug-but if you do then it can be "heli-coiled" as mentioned earlier and that is beyond my skill level.


I do not think you will have to do a head rebuild. I cracked a plug in my Mazda 626 many years back and it was about $100 something to have the plug removed and threads re-cut.

Good luck-let us know how this turns out we are rooting for you and the daughter. Good looking truck by the way.

Ritzy4Runner

iTrader: (1)

Thanks Ron, it has not been a good weekend! So what you are suggesting is to fully warm the truck up and then pull the plug? I'm thinking that for now I will just leave it as is untill she gets some of her trips out of the way. I hate tp put her truck down for a couple of weeks over this freakin plug. And the others I will go ahead and do when the engine is COLD! I haven't read anywhere in the FSM about using anti-seize, but I am always open to suggestions and recommendations on this and after I get it out. Thanks again

Ritzy4Runner

iTrader: (1)

Found a couple more threads (no pun intended) about stuck plugs and it was recommended to let it get "stone cold" and then attempt the removal. The writer stated "The plug will be difficult to remove but it will come out". He did not mention too much about the thread status but I'm wondering which is the best method, I sure hate to bugger this thing up any more then it is.

swampfox

if you end up tapping the hole use a good amount of bearing grease on the tap. this will help catch the cuttings. clean and grease as needed. i have rethreaded and used helicoils and it is not that bad to do.

OutlawMike

From a differential thermal expansion standpoint, the tapped hole in the head will grow larger in diameter as it heats up. The spark plug will also grow in size as it heats up, but at a lower rate, since it is made of steel and the head is made from aluminum.

I still remember proving this in school and thinking that it did not make sense at first. Even after seeing the calculations I still thought it was opposite, until we then did a lab on it and proved it experimentaly.

So, as far as using thermal expansion to loosen the fit between the two, doing it hot would be the method to do that. But, there may be other thread issues with doing it hot. With female aluminum threads there can be galling issues even at room temp with some iron bases male hardware. Stainless can friction weld to aluminum at room temp under the right conditions.

I would try it hot, with penetrating oil first. The suggestion that there is carbon buildup on the first couple of threads sounds like a good one.

Good luck

Thelast83inNJ

Spray the plug and crank it out, spray again, then run it back in. Do it over and over, run it out, spray, then run it in till the plug comes out. If you have to run a tap or rethread with heilcoil afterwards, fire up the motor without that plug to blow out any chips. You won't hurt anything.

betelnut

I love questions like this! While I don't know, I'd suspect that when plugs seize, it's not a coefficient of friction problem, but that the metals actually fuse together.

Can't wait to hear the input of other knowledgeable folks.

Ritzy4Runner

iTrader: (1)

Me either! I just am looking for the best option for sucess and not having to tear down my daughter's "new" truck, this has not been a very good weekend for me and my trucks. Before this happened, see what happened to me come Friday morning ... https://www.yotatech.com/forums/f2/s...-theft-210904/

So adding to my worries of her truck and not idling properly I have to deal with my 4runner.

yayfortrees

OutlawMike, I agree completely. What do you do when you want to remove one piece of metal from another piece of metal? You heat up the outer part to expand it. I.E. Tie-Rod end; old rusty nut/bolt, etc. I've seen it work so many times, that it would have to work here.

Gnarly4X, I can kind of understand where you're coming from, but bolts, or spark plugs in this matter, can gall up just as easily at room temp, as any other temp. The tighter the threads are, the more likely they are to gall up. (Speed also plays a large role in this, like using an air impact to remove bolts in aluminum threads. Personal watercraft will do this quite readily if you use an air impact wrench to quickly remove bolts.)

Ritzy4Runner, this is some food for thought, although I've never tried it. Hopefully somebody else will pitch in whether or not it is a good idea. If it is in fact carbon on the end of the plug, what about a Sea-Foam treatment to try and break it loose? I understand you're going to leave it until she gets done with some road trips, and that's a good idea. But you will have to deal with this at some point. You might even read up on spraying a very small amount of water in the intake while running. While I'm not telling you this is OK to do, or that it's a good idea, I've read that it works, and I agree with the logic (it steam cleans - the reason a head can look so perfectly clean after a head gasket leak). I'll leave the decisions up to you.

On the other hand, if it is only carbon residue, it should flake off relatively easy upon removal of the spark plug. And while it's not ideal to leave those carbon flakes in the cylinder before it's fired up the next time, they're not likely to cause much, if any damage.

I also like swampfox's and thelast83inNJ's suggestions. I have used them both before, and they can work like a charm. The back it out until it's tight, then turn it back in a little trick usually works like a charm. If it does mess up the threads, tapping it with a lot of grease is a viable solution.

When I first bought my current truck, I replaced the spark plugs (among other things) the first day, as any loving Toyota owner will do. I turned the plug on #2 cylinder about 2 turns and it was out! "That's not good" I said. Idiot PO had cross-threaded the plug, so I had to tap the hole. I was extremely fearful of the procedure, but used a lot of grease, would go about 1/4 to 1/2 turn, back it out and clean it. Re-grease it, go another 1/2 turn, and repeat. I felt confident that almost no metal shavings fell into the cylinder, and it held just fine without problems until the cam chain guide snapped many thousands of miles later. I'm only telling this story to let you know that it can work, and it's not a major ordeal, as long as you take your time.

Ritzy4Runner

iTrader: (1)

Sounds very solid yayfortress. I actually went to a site that was recommended in one of the threads I read and they had a video of how to use their product (forgot just now) and they used WD-40 or light grease. they also had an email for questions and asked that one abuot the shavings. they pinged me back and said to use a small vinyl tube and vacuum to retrieve the shavings and any that were left would not pose a problem on starting up the next time as they would be expelled out the exhaust manifold.

I do appreciate all the input guys and if anyone has any other suggestions that they have heard of or have used (prefer the ones used, LOL) please don't hesitate to add to this thread. My goal is to find a solution tha twill pose the least risk of major repair. I want to get that plug out but I am still really nervous on what to do. I'm sure this problem will come up again for someone else so keep the suggestions/solutions coming. When I do get the issue resolved, I will post what I ended up doing whether simple or complex!

RustBucket

iTrader: (1)

I agree with the statement that heating the engine will increase the gap between the plug and the head. The CTE of Aluminum is roughly twice that of mild steel (23 micron/m-C vs. about 12). I highly doubt that the yield strength of aluminum will be compromised at engine operating temperatures (threads won't strip worse for being hot).

I use generous anti-seize on all spark plug threads. I have had them out 30k miles after and they still turn smoothly!

Ritzy4Runner

iTrader: (1)

Thanks again to everyone on their suggestions. I'm thinking that right now I will leave her truck alone until it starts acting up again and then we will have to deal with it.

One last question regarding anti-seize, is there a particular brand I should use?

874runnersr5

that permatex is what i use.. no complaints

nate6145

I just went through this yesterday.

The number 6 plug had been in there for about 8 yrs. When I changed the plugs the last time it would not come out. This time, they were all like that. Over about a 3 hr period, I kept running them in and out, and spraying liquid wrench w/silicone on them each time. I did have to move up to a 1/2" ratchet handle on the number 6 plug. Each one made an awful screeching/popping sound almost all the way out. On each plug I was sure I was gonna see aluminum threads coming out with the plug. Although it was nerve wracking, I'm glad I did it. Idle rpm came back up to a reasonable level, and it is much smoother.

Yes, I know, I won't wait that long next time.

Recap: Lube, in and out, repeat, keep holding breath.

ETA: Absolutely use a small amount of antisieze on the threads. I used Loctite white high temp

sb5walker

It's not unusual for plugs to get tight in the head, especially if they've been left in too long or the motor is allowed to run rich for a long time - or if the rings are bad and it's burning oil. As mentioned upthread, deposits of carbon can form on the end of the plug threads, and that's what can cause the plug to get tight as you remove it: the gummed up end gets drawn up into the head's soft aluminum threads.

As a first step I would try to clear as much of the carbon deposits off as possible. Either a Seafoam treatment, or water treatment, or both:
http://www.toyotanation.com/forum/sh...70#post2946870 . . . https://www.yotatech.com/forums/f116...l#post51124041

Yes, water does work: http://www.files.thinksitout.com/Alt...f%20engine.pdf

You probably won't get all of the deposits off the end of the plug, but you'll get some of it and anyway it's good to clean out the cyls regardless. When it comes time to remove the plug, go ahead and use PB Blaster. Unscrew the plug until it gets tight, then spray some PB Blaster on the threads, and wait 15 minutes or so. Respray, and screw the plug back into the head a little bit. Then back it out again until tight, then screw it in again. Occasionally you can respray with PB Blaster. Keep at it, trying not to force the plug since the aluminum threads are soft, and obviously you want to avoid damaging them if at all possible. Eventually you'll get it. As far as getting the motor hot, the points made sound logical; I've never noticed much difference but it's worth a try.

As far as using anti-seize on the new plugs, it's a good idea. The copper-based ones are the best suited to spark plugs. Most of them are both high-temp and sensor-safe, and the copper helps conduct electricity which you definitely want. Some anti-seize compounds have a silicone grease carrier, and you should absolutely avoid those - they will kill your O2 sensor. I like the Permatex Copper the best - it has a semi-synthetic grease base which tolerates heat really well. Loctite's would be okay, but it contains silica which is sand, and I don't like the idea of using that in soft aluminum threads.

Whatever anti-seize you choose, use the stuff sparingly - a little does go a long way. Avoid getting it on the plug insulator or plug boots - since anti-seize conducts electricity, it could short out your spark before it gets into the cylinder.

Permatex Copper Anti-Seize:
http://www.permatex.com/products/Aut...ubricant_b.htm . . . http://www.permatex.com/documents/td...tive/09128.pdf
http://www.permatex.com/documents/ms...lish/09128.pdf . . . http://www.amazon.com/Permatex-09128.../dp/B000HBM8HU

Loctite Copper: http://henkelconsumerinfo.com/produc...997&VKORG=3450 (takes a while to load, be patient)

The Loctite White Anti-seize is a non-metallic formula designed for the food industry - I would avoid it for this application. http://www.akd-tools.gr/xmsAssets/Fi...i_seize_us.pdf
http://henkelconsumerinfo.com/produc...677&VKORG=3450

Another point is that I think some plugs must get tight more than others. I've never had a problem since I started using only Denso plugs - the factory spec K16R-U. They are made of a very high nickel stainless, and I've never had a problem getting them out.

And the final point is to change the plugs regularly. The spec is every 30k miles or three years, whichever comes first. But as the motor ages and begins to burn a bit of oil, you'll need to change them more frequently, say every 20k miles/two years.

BTW, it sounds like you may not have gotten to the number 5 plug yet. That one is the bear, but it's fairly easy if you connect, in order, the spark plug socket, a short (2-3") extender, a universal joint, and a long (8-12" extender. That makes it fairly easy to get in and out. When installing the new plug, just use the socket with short extender attached and get the threads started by hand. Then you can attach the u-joint/long extender/socket wrench to tighten. Also, be careful not to tighten the plugs too much. The spec is 13 ft-lbs which is not a lot. And it's best to tighten them once and leave them. The gaskets are designed to crush when installed, so they should be considered one-use only.

And by all means, don't just check and regap the plugs, they're cheap! Replace the buggers.

EDIT: Another good thing to do is to use a very small amount of dielectric grease on the white porcelain plug insulators - that will keep the plug boots from glueing to the plugs, which does sometimes happen, and you usually wind up destroying the plug boots trying to get them off.

yayfortrees

Great posting! ^^^

thefreqofnature

I just changed my plugs on Sunday. 88 3.0. The middle plug on the drivers side stuck baddly as I was trying to remove it. The engine was warm from going to get the new plugs when I was working on it.
Once the plug started getting difficult I stopped and tightened it back in a bit. I went back and forth, only about 1/8th if a turn, what ever it would give. A shot of WD-40 and one beer later. The plug came out with much less resistence.

I always put a light coat of nickle anti-seize on plugs when they go in.

Best of luck! Be sure and post up the good news!