Sorry to hear the news, Greg.

Although I'm as mechanical as most of other guys, this is my opinion.

Since Scalet was running fine until you fill up your tank, your first guess was gas. Then, the meachanic reported more serious problem so eliminated that possibility.
But I think, since I saw compression problem and thread on spark plug, it might be the gas with lot of water in it. I did see that no compression could blow out the spark plug but normaly, we get 11:1 compression. water instead of gas would change compression rate. I could be wrong but I think it could be combination of bad gas and loose spark plug.

Whatever the reason is, I hope Scalet comes back to you soon.

cheers,

 

Well, I just checked my plugs and they were all tight. So that can mean either:

- We've learned from our mistakes, or
- There is a problem with the plugs working their way loose after several miles

You also need to know that I only have 186 miles on this car so far. I would be really interested to find out if these plugs work their way loose after a period of time?

Thanks,
Bob

 

That would be real scary if these things worked themselves loose over time. I wonder if the crush rings on these plugs aren't doing their job. I'd hate to think you have to put Loktite on your spark plugs (j/k).

 

Greg, Just checked mine (build date July '99) plugs never touched, all tight, all checked.
JohnA

 

GREG.
Sorry to hear about Scarlet. I definately can relate to you, and we're some-what on the same boat. I'm waiting for a new short block for my S. I've been waiting for 2+ weeks already. My head is still at the machine shop for checking. You got no compression in your #1cyl, i have no compression in my #4 . Hopefuly everything will be smooth for you and for me.
Nick

 

 

Definitely something sus' here if there are no threads left on the head. I suspect more damage could be caused by all those metal threads falling down into the cylinder. I didn't read anywhere that the insulator on the plug was damaged (could we have some more details on that) and I would think that the spark plug cap would have held the plug tightly enough in place for it not to break a piece off. I also wouldn't think it would have got hot enough to melt the insulator if the plug was out of the cylinder head.

I agree with UL - there is a definite mismatch between assumed cause, effect and symptoms.

 

There is some good information here...even though all I can do is speculate on the actual cause of this failure, I do think that somehow it all started with the plug coming out of the head. And that was what motivated me to post this, so that others would not experience something so easily avoided. I don't think this is epidemic and I hope that I didn't cause anyone any undue paranoia. I also didn't think that it would be good for me to say nothing, even though the precise cause and point of failure is an unknown at this point.

I don't know how much I can believe the debris argument - meaning some piece of something fell into the cylinder. I think the piece of spark plug argument holds more water for me. The area below the spark plug cover is pretty well sealed off, so I don't think there is any real chance of something already in there falling or getting sucked into the cylinder. A piece of the spark plug makes more sense to me. Which may be irrelevant, actually, but I'm just trying to think through what happened here.

On the way to Indy for the F-1 races this weekend, we're going to stop by and see the car (with camera in hand, of course), so we'll get a glimpse into the actual motor and at that point we'll have a better idea of what happened.

The Service Manager was pretty baffled and as I said, this kind of thing has never been seen before by their service deparmtment.

Stay tuned, I'll post pictures when we get back on Sunday...

 

I may have missed this, but the information that I'm waiting for is whether the spark plug was actually broken. Greg - have you seen the plug? Were there pieces missing that could have entered the cylinder?

 

I also missed the part about the porcelain on the piston. That could certainly explain the retainer damage. However, the complete lack of threads on the #1 cylinder is still very suspicious. Windscreen's analysis of heat related issues is spot on, but that doesn't explain how the plug gets blown out and threads removed. I've seen 500+ hp Honda engine break rings, ring lands, etc. without ever blowing the plug out or damaging threads.

I look forward to some pictures and an analysis from Honda, but somehow I don't think we'll get the latter.

UL