Size of socket for GTV6 spark plug

[GTVMach1]

Hi,

I have tried a 16mm, 18mm and a 21mm socket for an 84 GTV6, none works.
Does anyone know what size plug and socket can be used on a GTV6?

I tried them also without the rubber insert (I thought some inserts were a little too long preventing the socket going into the plug). Didnt work.

3/8" was definitely too small.

Any idea what plugs could have been used by previous owner?

[AlfaTango1]

13/16" or 21mm will work but it needs to be thin walled.

[gtv27]

there is a factory tool that came with the car (if you can find one) or as per above, buy the slimmest 21mm you can find, and if necessary attack it on a bench grinder.

[Alfisto Steve]

Quote:

Originally Posted by GTVMach1 Hi, I have tried a 16mm, 18mm and a 21mm socket for an 84 GTV6, none works. Does anyone know what size plug and socket can be used on a GTV6? I tried them also without the rubber insert (I thought some inserts were a little too long preventing the socket going into the plug). Didnt work. 3/8" was definitely too small. Any idea what plugs could have been used by previous owner?

[GTVis4me]

I had to grind down a regular one last year cause I couldn't find a thin wall and needed it right away. It still works. If you can find a hardware store with a grinding wheel they'll do it. Mine did it for free.

[sh0rtlife]

i recommend pulling the valvecovers and making sure that there alignment with the head is PERFECT..i used 3 fat sparkplug sockets as alignment pins...now i can actualy use a "normal" spark plug socket and dont need a thinwall any more...mind you i cant use any realy fat ones but im not forced with a realy thin wall one

[GTVMach1]

Thanks to all of you who replied. I'll grind down a 21mm socket

[Alfisto Steve]

Quote:

Originally Posted by GTVMach1 Thanks to all of you who replied. I'll grind down a 21mm socket

[karmat]

My new GTV6 has about the tightest fit of any V6 car I've seen. I had a thinwall plug socket that worked on the original 2.5L motor in my old car, the 3.0L I put in it, and the 3L in my Verde. But it wouldn't fit in this car, even with the valve covers lined up. I was getting ready to grind one down and someone said the Craftsman socket will fit. I thought, heck why not?

Perfect fit, with a tiny bit of play. I'd start there.

Karl

[chasgtv6]

I use a 13/16 socket ('82 GTV6) stamped "EASCO USA" bought at a local Murray's auto parts store. No grinding needed, fits in hole as is

[Alfar7]

Just convert to a 3/4 reach 5/8 hex plug and life is much simpler at plug changing time.

[chasgtv6]

re. 3/4reach etc.........Brand?? heat range?? Thanks