Loose spark plugs

[efnfast]

So, couple weeks ago had #8 plug blow out. That ain't good. Figured it was just cause you can't get it torqued properly with all the swivels and extentions ect. I blamed it on the mechanic, yes, that would be me.

Figured I should check the others. One was still torqued to the 25 pounds I put it in at. All the others moved, some were finger tight.

Yud up with dat? -Steve

[Schrade]

Saw the title, and said, I'll post that I'll take a plug blown out of the hole over a stripped head any day.

I seated a plug once in an LT1, thought it was tight, then gave it just a TAD more...

I felt a 'give', and got a sick feeling in my gut in an instant.

It was the gasket compressing...

[Mystic ZR-1]

Steve
What do you mean by blow out?
Did it take the threads with it or just back out?
Doug

[XfireZ51]

There was a discussion about this once before. I had used anti-seize but now just a light film of oil. Just pulled a couple of plugs the other day after 600+ miles. Plugs still torqued. Just my experience.

[WVZR-1]

If yours is a '90 what spark plugs were you attempting to use. What did you remove for spark plugs when you did it? You sourced your torque values from where? I have friends that insist on using "anti-seize" and others that insist those that do are "foolish" - I might add that a friend that does uses a "nickel" base for them and is specific about "sparingly" when questioned. Ford specifies a nickel base product that is quite expensive!

I believe that most spark plugs now are "nickel" coated and I read not long ago that most if not "all" spark plug manufacturers mention NOT to use specifically. The subject is debated frequently for sure!

[efnfast]

Steve
What do you mean by blow out?
Did it take the threads with it or just back out?
Doug

I was parked at the top of an exit ramp and the car started makeing a horrible noise. Shut it off and started looking around, there was #8 wire hanging to the side. I looked up the ramp and there was my plug.
I walked over to the Subaru dealer, and a mechanic let me borrow some tools. Screwed it in and everything seemed fine. It must have cost me a couple threads at the top, but screwed in with no issues. It was a beuatiful day, I was alone, and had no place to be. Could have beena lot worse.

[efnfast]

If yours is a '90 what spark plugs were you attempting to use. What did you remove for spark plugs when you did it? You sourced your torque values from where? I have friends that insist on using "anti-seize" and others that insist those that do are "foolish" - I might add that a friend that does uses a "nickel" base for them and is specific about "sparingly" when questioned. Ford specifies a nickel base product that is quite expensive!

I believe that most spark plugs now are "nickel" coated and I read not long ago that most if not "all" spark plug manufacturers mention NOT to use specifically. The subject is debated frequently for sure!

I was/am using NGK iridium tipped one heat range cooler than stock. I think these are a tappered seat, but all of our heads are machined for both gasketed and tappered seats. Used the dip stick to put a drop of oil on the threads.
Removed AC's.

[WVZR-1]

The first time use of the taper seat on early heads requires an over-torque to establish the seat, backed off I thought and installed using the correct torque and they are NOT machined to accept BOTH. They will accept either but after the first taper seat install I would think that's what needs to be used there after. I believe the over-torque required was something in the vicinity of what you mention yours were installed at. Haven't seen the procedure for some time. The AC's were of which variety?

What's the number of the NGK used? I'd think it needs confirmed to be either flat requiring a gasket or a TS plug.

[efnfast]

Plugs were recomended by Marc H.
He informed me that all the heads were machined for both.
Not sure of the AC's, they're at home.
I might have a note about the NGK's in this computer somewhere.

Found it, this is exactly what I did.
The following is a quote from Marc when I asked him about plugs.

Hi Steve,

For high load operation I recommend a spark plug that is one AC heat range cooler than the OE plug. The best spark plug is the NGK TR7IX. Part number 3690.

It has a tapered seat. All LT5's are machined for both tapered and flat seat plugs. Carefully open the gap to .050"

Best of luck.

Marc