The damn #8 spark plug on LS1 motors...

[96Firebird]

Is killing me slowly.

Decided to change the plugs on my Trans Am today, perfect idea on a 90 degree day. Got the first 7 replaced within 2 hours, then spent the next 2 hours trying to get the #8 plug out. Not happening...

I tried using a swivel like a lot of people online say, but that wasn't happening. The 3" extension is too long, but my spark plug socket has a 3/4" hex on the end so I used a 3/4" socket and tried that. Got it on, but couldn't get the leverage to get the plug to turn. Wasn't budging, gave up on it. I think my next step is to try from underneath, I have a little more room with my longtubes headers.

Is there anything I can spray on the plug to hopefully loosen it a bit? Keep in mind these are aluminum heads, and I don't want to use anything that can corrode the aluminum...

I'm wondering if this plug was ever replaced in the past, the others started turning with a little force but this one is stuck.

 

[leper84]

IIRC when I had a LS1 Fbody I did #8 from underneath. Don't worry about spraying any wd40 or pb blaster, not gonna hurt anything. Just don't use anti-seize on the plugs w/ aluminum heads.

People skip that plug pretty frequently....

 

[boomerang]

Don't bother spraying anything as nothing is going to get past the tapered seat. By design it seals the combustion gases from leaking out and will therefore keep anything from leaking in.

 

[Jimzz]

Yep go under that car/motor setup to change some of the plugs.

 

[Slacker]

There is a special service tool for that, here.

 

[local]

Yep I do most of them from underneath. Takes about 20 minutes now that I know exactly how to do each one.

 

[eng2d2]

Is killing me slowly.

Decided to change the plugs on my Trans Am today, perfect idea on a 90 degree day. Got the first 7 replaced within 2 hours, then spent the next 2 hours trying to get the #8 plug out. Not happening...

I tried using a swivel like a lot of people online say, but that wasn't happening. The 3" extension is too long, but my spark plug socket has a 3/4" hex on the end so I used a 3/4" socket and tried that. Got it on, but couldn't get the leverage to get the plug to turn. Wasn't budging, gave up on it. I think my next step is to try from underneath, I have a little more room with my longtubes headers.

Is there anything I can spray on the plug to hopefully loosen it a bit? Keep in mind these are aluminum heads, and I don't want to use anything that can corrode the aluminum...

I'm wondering if this plug was ever replaced in the past, the others started turning with a little force but this one is stuck.

I almost bought jamie curtis transam but I didnt for this reason. You could try liquid wrench.

 

[Dulanic]

This thread makes me miss my firebird from when I was a kid... Loved that car. And yes that #8 is a PITA.

 

[MongGrel]

My cousins old Mercury Cougar was a real PITA when I took my Camaro up to his farm to do tune ups.

Had to take the headers loose just to change the slant spark plugs.

We did a lot of weird things in the 70's, still surprised we didn't blow up in an explosion cutting the back bolts of the leaf springs near the gas tank with an acetylene cutting torch when we put shackles and air shocks on my Camaro.

Was a thing once upon a time I guess.

Farm boys did odd things to old cars once upon a time, I was never really a farm boy but a lot of my relatives were and I was there enough to almost be qualified