Need to fabricate a special wrench to tighten up the flexplate bolts on my GTA. It's an 87 with the 350 TPI. But I can't determine the bolt size to make the wrench because a std. wrench is too thick to get in between the flexplate and torque converter. Just need to tighten them enough to crank car and add antifreeze. Will pull trans and repair correctly next spring.

They look to be about 15 mm but can't be sure.

Phil

 

Kinda tuff being a newbie to the forums. Gotta earn a little respect I guess.

 

Hey, Phil,

Don't know if this will help or not. According to the Jeg's cat flexplate bolts for a Pontiac are 1/2" x .670" Pro.

JamesC

 

Thanks James. What I am actually looking for is the bolt head size or wrench size.

Phil

 

I was able to get to mine with no problem - wrenches were el-cheapo brand from Autozone - like $20 for the whole set - sometimes the el-cheapo tools come in handy - as in this case - not so thick!

 

Now for the BIG question!
What size wrench would that be?

 

I'm not an automatic kinda guy, so I'm a bit clueless. I did a search and couldn't find anything definitive. I suggest you post again, titling it something like "Bolt Head Size for....

JamesC

 

i've tightend, installed, and removed a couple of TC to flex plate bolts and used whatever wrench was handy. the way i figured out the correct size was by putting a wrench on the bolt/nut untill i found one that fit. if it were me i'd start with a 9/16 wrench and go from there.

 

As i mention above, I have no experience with automatics. Seems I did read that the size MIGHT be 11/16. Sorry, probably just confusing the issue.

JamesC

 

EDE, My point is there is not enough room to put a std. thickness wrench in there to find out what fits. So I will have to grind down a wrench to get in there. I don't want to start grinding a nice wrench just to see if it will fit. I can buy a long thin special wrench but I still need to know what size.

Maybe that makes it a little clearer.

Phil

 

Does anyone else agree that this may be a 11/16 bold head on the flexplate?
Thought I would ask just one more time before I start grinding down wrenches.

Phil