Spark plug questions

[hiperf406]

I went to an all Corvette show on Sat., after show was done I headed to the Pavilions Sat car show. On the way home the car was running great, turned off freeway & went about a block off suddenly the car started making a horrendous noise. I pulled over & checked it out #3 spark plug was gone, it had backed out & was gone. Got car flatdecked home & checked plugs they all were loose. Today I'm going to change plugs but checked Solutions & a couple are mentioned. I was wondering if NGK or AC Delco part numbers were still applicable. Also what is the torque value for plugs. TIA :confused:

lorne #1748

[Dynomite]

For my 91' NGK Iridium BKR5EIX Eagle
Gapped .043"
http://i287.photobucket.com/albums/ll142/dynomite007/91%20ZR1/NKGIridium.jpg

I do not use a torque wrench on spark plugs or some other items. I just tighten (snug but not too tight) with a short handle 3/8 socket wrench and call it a day.

That is one of those items I DO recheck tightness once in a while as the plugs are easy to get to. I also place just a bit of white greese around the Boot ring that fits near the top of the spark plug hole to make the Boots easier to remove and to help seal them.

Use just a bit of antisieze on the plug threads.

http://i287.photobucket.com/albums/ll142/dynomite007/91%20ZR1/Permatexantisieze.jpg

Number 8 Spark Plug Removal and Test Drive with Jeff Gordon (http://forums.corvetteforum.com/c4-zr-1-discussion/3005470-tech-info-lt5-modifications-rebuild-tricks-500-hp-5.html#post1581827106)

[Kevin]

a plug backed out? That's the first i've heard of this happening. I blew a plug out fo the head of my mustang once, but never heard of this on a zr-1

[Z51JEFF]

a plug backed out? That's the first i've heard of this happening. I blew a plug out fo the head of my mustang once, but never heard of this on a zr-1

This is the second time Ive heard about this happening.

[Racinfan83]

Yeah there was another thread on here a few months ago where that happened. Good reminder - I have to change my serpentine belt - think I will check the plugs while I'm at it since I changed them last fall...

[efnfast]

I blew #8 out, but that's the one you can't put a torque wrench on.

[efnfast]

This was an e-mail from Marc H.

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

[hiperf406]

Yeah it really surprised me too, I thought the rubber boot should have retained the plug but it was nowhere to be found!! Thanks for the answers.

lorne #1748

[WVZR-1]

a plug backed out? That's the first i've heard of this happening. I blew a plug out fo the head of my mustang once, but never heard of this on a zr-1

It's been mentioned more than just "a few" times.

OP - What is in it presently for spark-plugs? I'd certainly start there with a check to see what is in the rest of the "holes"!

The anti-seize use I believe is often debated! The which to use anti-seize is also debated!

NGK has a comment regarding it's use:

http://www.ngksparkplugs.com/pdf/tb-0630111antisieze.pdf

[Dynomite]

It's been mentioned more than just "a few" times.

OP - What is in it presently for spark-plugs? I'd certainly start there with a check to see what is in the rest of the "holes"!

The anti-seize use I believe is often debated! The which to use anti-seize is also debated!

NGK has a comment regarding it's use:

http://www.ngksparkplugs.com/pdf/tb-0630111antisieze.pdf

NGK says this:
"Summary
All spark plugs that have a blackened or dull appearance on the metal body offer no protection against seizing or bonding to the cylinder head and so it is with these spark plugs that anti-seize would be required."

"Applying anti-seize to the threads of spark plugs that have a metal plating allows the installer to mistakenly over-tighten the spark plug in the cylinder head."

One reason I do NOT use a Torque Wrench on Spark Plugs but rather I just tighten (snug but not too tight) with a short handle 3/8 socket wrench and call it a day.

[PhillipsLT5]

I am using NGK Iridium TR 71 X, pricey but last plug I probably will buy

[chriskinzel]

I have had one of mine find the road as well. two others where lose at the same time (no wonder it was running so poorly!).

[efnfast]

It makes a hell of a racket when one comes out.

[Jim Nolan]

Could the plugs being loose or coming out the result of some time in the engine's past the plugs being removed when the motor is still hot?

[scottfab]

Could the plugs being loose or coming out the result of some time in the engine's past the plugs being removed when the motor is still hot?

More like put in when hot/warm.

I use anti-seize on just the top two threads
(farthest away from the spark tip).
This ensures none get in too deep.
The idea is to reduce the total max friction
should one plug want to resist coming out
(dissimilar metal bonding)
In 17yrs I've never had a plug come out or even loosen on
the ZR-1. On my 73 BB I did several times.
I torque to 20lb (http://www.youtube.com/watch?v=RywJJUY3TKY).

[hiperf406]

Well got all my plugs changed & took car for a drive. Before I changed the plugs the car had a significant miss in it - which I attributed to my injectors as am still still running original injectors. On my test run car ran great no miss at all & it seemed to pull stronger. The plugs looked good with a light brown color to them. It took longer to change # 8 than to do all the rest !

lorne #1748

[scottfab]

...snip...
It took longer to change # 8 than to do all the rest !

lorne #1748

Welcome to the "Knuckle Busting #8" Club =D>

[Racinfan83]

It took longer to change # 8 than to do all the rest !

I actually had more trouble with #7 then I did with #8.... :o

[Paul Workman]

I am using NGK Iridium TR 71 X, pricey but last plug I probably will buy

I follow Pete's philosophy; replace often, have a fresh set in the motor as much as possible.

A "gee wiz" exotic rare earth plug might last a lot longer, but the insidious half-life degradation is also longer.

On the other hand, the conventional copper core AC/Delco 41-602s can be had for about $2.00 + tax ea. and are good for at least 10k miles. That means my Z will have a fresh set in it for under $20 every season (≈ 3000 miles or so) well above their half-life performance threshold, and perhaps superior to a rare earth plug in it's twilight phase. And, considering how easy it is to replace plugs in an LT5, I don't see any down side to using the conventional plugs.

Your mileage may vary...

[XfireZ51]

I use a standard plug and a bit of oil for anti-seize. I found that using regular anti-seize allows the plug to loosen often. As for the plug, it's a NGK BKR6E.
When you view the ground strap for correct heat range, the 5 is too hot, and the 7 too cold. It's the Goldilocks plug. I also gap to .035". A .050" appears to give you a smoother idle, but puts more of a load on the coils top end.

[Paul Workman]

Well got all my plugs changed & took car for a drive. Before I changed the plugs the car had a significant miss in it - which I attributed to my injectors as am still still running original injectors. On my test run car ran great no miss at all & it seemed to pull stronger. The plugs looked good with a light brown color to them. It took longer to change # 8 than to do all the rest !

lorne #1748

For what its worth, I've NO problem with either #7 or #8.

I bought a Craftsman plug socket with the swivel on it, and using a short extension it all follows easily down the hole, leaving the end of the extension just above flush with the cam cover (when seated fully over the plug) where an additional swivel may be installed. Or, depending on the length of the extension, swivel-head ratchet easily accesses it, no problem!

Maybe its all relative. After changing plugs on my LT1 Vette,:censored: changing the #8 on the LT5 is nothing in comparison!:)

http://i185.photobucket.com/albums/x220/6PPC_bucket/tech%20files/Sparkplugtool_zps927b1581.jpg (http://s185.photobucket.com/user/6PPC_bucket/media/tech%20files/Sparkplugtool_zps927b1581.jpg.html)

[Dynomite]

For what its worth, I've NO problem with either #7 or #8.

I bought a Craftsman plug socket with the swivel on it, and using a short extension it all follows easily down the hole, leaving the end of the extension just above flush with the cam cover (when seated fully over the plug) where an additional swivel may be installed. Or, depending on the length of the extension, swivel-head ratchet easily accesses it, no problem!

I'll take a pic of it and post it later.




Blackhawk 5/8" Spark Plug Swivel Socket 3/8" Drive :thumbsup:

http://i287.photobucket.com/albums/ll142/dynomite007/D%20Engine%20LT5/44a79c6a-500f-42c2-8e71-028e1072c81b.jpg

[csavaglio]

I just did mine and I was surprised about the #8 after all the negative stuff I've heard. I had no problem. It did take longer than the others, but, being the first time, it took a little experimenting to get the right combo of extensions and u-joint.

After dealing with LT4's, LT1's, L98's, and an L98 with long tubes where I had to run shorty plugs and make a plug tool just to get to them (a short plug socket with a notch cut in one side to slide sideways onto the plugs since the headers didn't allow a direct approach), the #8 on the LT5 was barely noteworthy. The only motor I've had that was easier was a stovebolt 6.

Personally, I've never run fancy plugs, although I run platinums in my LT4 since they're a bit more of a chore to change. I am running platinum rapid fires, but on this motor, I still don't mind changing the plugs once a season (don't mind the minor expense and it's not hard).



Chris

[scottfab]

F
....snip....
Maybe its all relative. After changing plugs on my LT1 Vette,:censored: changing the #8 on the LT5 is nothing in comparison!:)




I think that is it in a nut shell. I've never had an engine that was so easy
to change plugs as the LT5 is. The only plug offering any complication is #8 and it is equal in difficulty to the easiest plug on my Explorer.
It truly is just relative.

[Racinfan83]

Blackhawk 5/8" Spark Plug Swivel Socket 3/8" Drive :thumbsup:

http://i287.photobucket.com/albums/ll142/dynomite007/D%20Engine%20LT5/44a79c6a-500f-42c2-8e71-028e1072c81b.jpg

I got one of those and it made the job a hella lot easier. The only issue I had was the plugs wouldn't stay in the socket - but a strip of electric tape inside the socket fixed that issue...

[XfireZ51]

I got one of those and it made the job a hella lot easier. The only issue I had was the plugs wouldn't stay in the socket - but a strip of electric tape inside the socket fixed that issue...

You can use a piece of hose to screw plug into hole, then use socket to give it the final torque. I use telescoping magnet handle to pull plug out of well.

[Schrade]

I was sinking some new plugs in an LT1 once, and one of 'em didn't feel 'right' (had anti-seize, and didn't quite feel cross threaded). I backed it out and tried again, still funny-feeling. I got near the bottom, and it really was gettin' tough.

Then it seemed like it broke loose. I got a sick feeling in my gut. Screwed in in a little more, and it locked down. I left it, and it was probably under torque spec.

I'd rather blow a plug, than buy another head.

[Dynomite]

I got one of those and it made the job a hella lot easier. The only issue I had was the plugs wouldn't stay in the socket - but a strip of electric tape inside the socket fixed that issue...

Those swivel Spark Plug Sockets have a nice rubber insert. My only issue was that the spark plug held on to the insert separating the short wobble extension from the end of the swivel socket when done inserting the spark plug. A little white grease on the rubber insert cured that issue :thumbsup:

http://i287.photobucket.com/albums/ll142/dynomite007/Dynomite6/c38633f3-a0c2-4f87-8c03-45bf5dcb934f.jpghttp://i287.photobucket.com/albums/ll142/dynomite007/Dynomite6/f532070e-4de8-432b-9da9-30984aa1362b.jpg
http://i287.photobucket.com/albums/ll142/dynomite007/D%20Engine%20LT5/44a79c6a-500f-42c2-8e71-028e1072c81b.jpg

[Hog]

Just for clarity, a spark plug should NEVER be broken loose with the engine hot. The risk of removing teh aluminum threads along with the plug.

There were some mid 90's 4 cylinder engines that had shop instructions that recommended that the car sit for 24 hours before attemptuing to remove the sparkplugs.

I once had a buddy that came to my shop and wanted to change the plugs. It was a GM product that had the Quad 4 engine. I told him to "at least wait a few hours to let it cool down."
Hje said " No its OK, lets do it now, it'll be OK".

So he went and got the sparkplug sockets and 3/8 ratchet and an extension. He is struggling, and I laugh and continue working away on my truck down in the pit.

After a few minutes I hear "Oh SH*T, damn ^*(^&&( curse, curse, curse".

I get out from under my truck and I see that he had a 1/2" drive 3 foot long Johnson bar, with a 1/2" to 3/8" adapter on it. He holds up the plug, and it had a bunch of aluminum on it.

I didnt even say I told you so. At least he stopped, and didnt try the next plug. The car sounded like a tractor as he pulled out of the driveway.

I'm not sure what the LT5 recommendations are, my point is to just execise caution and leave the Johnson bars in the toolbox.lol

[Hog]

Specced a 1991 LT5

ACDELCO FR2LS Copper Core
Alternate/OEM Part Number(s): 05614062, 05614285, 5614062, 5614285, FR1LS $1.58
http://i1202.photobucket.com/albums/bb373/Paul_Schermerhorn/Engine/delcocoppercore_zps46d81ae1.jpg (http://s1202.photobucket.com/user/Paul_Schermerhorn/media/Engine/delcocoppercore_zps46d81ae1.jpg.html)

ACDELCO RAPIDFIRE PLUG "#5"
Alternate/OEM Part Number(s):
19145287, 19238456,19250964,19308030 0.045" $3.59 or ($3.25 from GM Parts Direct)
http://i1202.photobucket.com/albums/bb373/Paul_Schermerhorn/Engine/delcoplatinum2_zps581108ff.jpg (http://s1202.photobucket.com/user/Paul_Schermerhorn/media/Engine/delcoplatinum2_zps581108ff.jpg.html)

ACDELCO 41800 Platinum
Alternate/OEM Part Number(s):19238465, 19250972, 19305821, 88901006
0.35"gap $5.02 ($5.33 from GM Parts Direct)
http://i1202.photobucket.com/albums/bb373/Paul_Schermerhorn/Engine/delcoplatinum3_zpsb9082a22.jpg (http://s1202.photobucket.com/user/Paul_Schermerhorn/media/Engine/delcoplatinum3_zpsb9082a22.jpg.html)

Specced for 1995 LT5

ACDELCO PLATINUM PLUG Part # 41913
Alternate/OEM Part Number(s):05614355, 19158035, 19208528, 5614355
0.35" gap $1.74
http://i1202.photobucket.com/albums/bb373/Paul_Schermerhorn/Engine/delcoplatinum19951_zps925a3ade.jpg (http://s1202.photobucket.com/user/Paul_Schermerhorn/media/Engine/delcoplatinum19951_zps925a3ade.jpg.html)

ACDELCO RAPIDFIRE PLUG 0.035" ACDELCO "8"
Alternate/OEM Part Number(s):19145290, 19238459, 19250967, 25171347
0.35" gap $2.05
http://i1202.photobucket.com/albums/bb373/Paul_Schermerhorn/Engine/delcoplatinum19952_zps1a341a03.jpg (http://s1202.photobucket.com/user/Paul_Schermerhorn/media/Engine/delcoplatinum19952_zps1a341a03.jpg.html)

ACDELCO #41963 PLATINUM PLUG
Alternate/OEM Part Number(s): 05614355, 19158035, 19158040, 19208528, 19208532, 19244470, 25178637, 41913, 5614355
$5.02
http://i1202.photobucket.com/albums/bb373/Paul_Schermerhorn/Engine/delcoplatinum19953_zps9f10c261.jpg (http://s1202.photobucket.com/user/Paul_Schermerhorn/media/Engine/delcoplatinum19953_zps9f10c261.jpg.html)


ACDelco Spark Plug Rebate
Offer expires 12/31/2014

Get up to $2 per plug back by mail in rebate.
• Professional Iridium ($2 per plug)
• Professional Platinum ($1.50 per plug)
• Rapidfire ($1.00 per plug)
• Professional Conventional ($.50 per plug)


AC/Delco Mail in Rebate for lugs
http://www.acdelco.com/pdf/2014-Spark-Plug-Rebate-Pad.pdf


Heck for the price of the Copper Cores, you can swap out a full set of 8 every year for $12.50. We have spark plugs up here that go for 20+ dollars a piece.

The Copper Core plugs conduct electricity better than the rare Earth elements(REE). This would NOT be noticeable via a "Seat-Of-The Pants"(SOTP) dyno test.
The REE's have the advantage when it comes durability. Hence why they became OEM almost across the board as GM increased it warranty from 3years 36,000 miles, up to 5 years/100,000 miles.

Knowing you have to change a Copper Core plug more often can be viewed as desireable as it forces you to pull them and inspect them. While you are at it, you might as well do a compression test while you are at it.

[scottfab]

This from a Delphi Spark Plug Engineer.

**************************************
.....snip....
Additionally, always remember these three things when installing new plugs: 1) Gap is important! 2) Installation torque is critical for proper heat dissipation. Tapered seat plugs should be installed at 11-15 lbs/ft and flat seats at 18-22 lbs/ft in cold aluminum cylinder heads. Reduce these specs by 30-35% if using a light coating of nickel or copper based anti-seize compounds. 3) A light coating of silicone grease inside the spark plug boot will increase the protection against arcing over (flashover).

Regards,

Mark Weaver
Delphi Spark Plug Engrg.

[Racinfan83]

Those swivel Spark Plug Sockets have a nice rubber insert. My only issue was that the spark plug held on to the insert separating the short wobble extension from the end of the swivel socket when done inserting the spark plug. A little white grease on the rubber insert cured that issue :thumbsup:



That was the problem I had. And I greased it and it still came out of the socket - and with all my messin with it I got grease on the outside of the rubber insert. At that point I said "screw this" and went with the electric tape...;)
My wife is using some spray glue on a craft project now - I may go spray that on the rubber deal and see if I can make it stay in the darn socket..lol