Pinky

Time-sert. I bought the kit and did it myself. They say that they are self locking but if you use a very slippery grease when cutting the hole it might not hold like it should. You could use RED thread locker if you are worried that is for permanent hold vs. blue which is temporary.

The kit I had now sits at a shop in New Hampshire that will get more use out of it than me. It was a little thank you for all the help he has given me over the years. If I ever need it(hope never to) I will just borrow it back.

MM3Kwolik

I personally use a little RED loctite on inserts for Spark Plug thread repair. It's not really necessary, but I always do just for added assurance since the plugs get pulled semi-frequently. I usually use a long, large cotton swab with some brake parts cleaner to clean the threads before installing the insert. I have always had 100% success with this and have saved customers thousands of dollars over what Honda wanted to charge them.

iamxpl

also going forward buy yourself a proper torque wrench for those plugs =) happy motoring.

sbman

I appreciate all the tips here and look forward to fixing the issue.

With this exception. I suppose intended to be helpful. Ah yes, it must have been the dumb owner not tightening them down properly.

For the record, these plugs were installed by the dealer. They were installed under warranty because the exact same thing happened (on the same cylinder) while the car was under warranty from the factory installed plugs, although I was told at the time that there was no damage to the head, because I asked. The symptom was much more obvious then, the computer came up with a misfire cylinder 3 and I took it in immediately. This time, no computer code was thrown until all contact between the plug and head had been lost and it also started running on 3 cylinders suddenly with no prior codes thrown. Possibly I should try to chase this down with them, but it would be a difficult battle because it's been so long in calendar time and I have no way to prove that the plugs are still the same exact ones they put in under warranty and no one has touched them since.

If the factory can't get them right, and the dealer can't get it right, what could I have done to make the situation better? Not trying to start a flame-war, it's an honest question. Should I start checking plug tightness ever 5K miles?

The plugs have not yet reached their first service interval according to the Honda maintenance schedule and should not have needed to even be touched yet, and I know I never have, only the factory and the dealer has ever touched the spark plugs.

Pinky

There was a TSB released increasing the Factory Torque specs but we have found that even that INCREASED torque is still not sufficient 100%. The recommended spec here is 20-22FP.

Unless the dealer got the updated info they would have done what the factory did which was NOT ENOUGH really putting you behind the curve.

notaloafer

HEY now! I used a heli-coil in my 1985 Toyota Pickup (basically the EXACT same engine/specs as the s2000) and it never gave way! I even threaded the spark plug itself with red loc-tite - little bugger never came out, ever again.

I'm offended.

Slowcrash_101

Did your 1985 have the same amount of compression as the s2k motor? Did your pickup rev to 9000 without balance shafts?

Slowcrash_101

I say you really should be careful because much more than 25~26ft lbs and you'll essentially ruin the threads in the head changing plugs or removing plugs, even with anti-seize. I'd say about 70% of this car has to be worked on with the level of precision as if it were an airplane, otherwise you run the risk of damaging things. To me that's what makes it fun in a way.

notaloafer

I was joking...

iamxpl

I was in no way trying to blame you or make you look bad so that was not my intention. Dont always believe the dealer as they are not always right and most of the times. I have proven to myself that the dealer actually knows less than most people give them credit for. As stated by Pinky, there was a TSB released that improper torquing of the plugs were being utilized in the service manual. There has been countless threads here of spark plugs backing out. A friend of mine who bought my old car used to work in a shop with me, and while i was changing my spark plugs on my new car I had asked him to help me. He did the old fashioned method of "good and tight" as many others have done so before. I asked if he used the torque wrench, and he said that they are good. I specified 21-22 lbs of torque as specified by Billman. * Im writing this off the top of my head but im pretty sure thats what the thread here suggested. He was skeptic at first since he thought that he had put them in by feel pretty tight already. So i broke out my 3/8 CDI split bar torque wrench and set it to the proper torque and handed it to him. He then started to go over the spark plugs and had a worrisome look on his face, it is quite an eerie feeling tightening the plugs at that range. 22 ft lbs of torque doesnt seem like much but it actually requires a good amount of force to achieve.

You may think this is overkill and if you're happy with having the dealer service the car then I cant tell you otherwise. But as one enthusiast to another I suggest looking over the DIY list here and check out what the other owners have found over the years.