Spark plugs, heads, vin #

[lwhssh]

1990, I can't tell for sure from my owners manual if I have aluminum heads or not. They appear to be. Would the VIN # identify what type of heads I have?
I want to change my spark plugs. 55,000 miles and I don't know if thats ever been done. (AC FR5LS)
Is there a trick to changing out the right side (passenger side)?
WHAT DO I HAVE TO PULL THE ENGINE OR REMOVE THE AIR CONDITIONER???
I can't see them, I can barely feel them. It doesn't look easy and I would hate to cross thread them in an aluminum head. Whats the trick?

 

[nyernga]

Is there a trick to changing out the right side (passenger side)?
WHAT DO I HAVE TO PULL THE ENGINE OR REMOVE THE AIR CONDITIONER???
I can't see them, I can barely feel them. It doesn't look easy and I would hate to cross thread them in an aluminum head. Whats the trick?

Just did mine last weekend. One school of thought is to remove the inner fender well. I just removed the AC bracket to get to the front 2 plugs. As long as you have a long extension and a swivel joint, you can get to all 4. Time, patience and a thin wrist is all you need. And whatever you do DO NOT crossthread the hole. I had to re-tap the one on my drivers side but it turned out fine.

Len

 

[Hrtbeat1]

1990, I can't tell for sure from my owners manual if I have aluminum heads or not. They appear to be. Would the VIN # identify what type of heads I have?
I want to change my spark plugs. 55,000 miles and I don't know if thats ever been done. (AC FR5LS)
Is there a trick to changing out the right side (passenger side)?
WHAT DO I HAVE TO PULL THE ENGINE OR REMOVE THE AIR CONDITIONER???
I can't see them, I can barely feel them. It doesn't look easy and I would hate to cross thread them in an aluminum head. Whats the trick?

From '87 on all Vettes have aluminum heads, they were introduced late in '86 model year. The easiest way to change the plugs is to remove the center section of the passenger fender well, above the A arm, I think there are 5 screws that secure it. There may be one or two in the bracket that holds the A/C lines that may need to be removed also. Once you get the center section off Long skinny arms help to reach in through the opening and to the plugs. I'm not sure which is the toughest #8 or #2 but either is a pain. Nyernga has a good point about the long extention and swivel. I always end up with about every extention / swivel I have. Just be sure to take your time. Use a little anti-sieze on the threads of the plugs and start them by hand. Dexterity and hand eye coordination (or lack of 'cos you can't see your hand in there) is very helpful also.

Good luck and welcome to

 

[Edmond]

It can be done without removing the well, that's the way I managed to do it. Then again, I have small hands so that really helps out. The hardest thing for me was making sure the boots snapped into the plug end.

 

[Vettefan87]

I haven't removed the the fender well, and I have changed plugs on my vette 4 or 5 times. All you have to do is go through the hole in the fender that is there. You do need a swivel to get them out.

 

[c4cruiser]

The hardest plugs on the right side is the #6 and #8 plugs. Use a socket with a hex-head end and use a box-end wrench on the socket to get the plugs loose.

On the left side, remove the center and rear part of the lower wheelwell housing and the plugs are pretty much a straight shot. Having about 14-18" worth of extensions will be a big help on this side.

Make sure the engine is COLD when you pull the plugs. The steel male threads on the plugs can easily strip the aluminum threads in the heads if the engine is warm.
When you install the new plugs, use some anti-seize on the threads and torque to about 11-12 ft-lbs.