Removing Stock 2JZ Head Bolts - "10mm bi hexagon wrench" ?

[jdemara]

Hey

I am trying to remove the stock head off my 2JZ-GTE. The manual says to use a "10mm bi hexagon wrench" which MUST be wrong. I have done some reading and many are saying it is a 12point 12mm. I have also read mixed comments about using a triple square. So, I picked up one of these with a M12 in it:
http://static.summitracing.com/global/images/prod/large/wmr-w1395_w.jpg

Problem is, this does not feel like it fits right, there is some wiggle room and can be moved left to right (doesn't feel as snug as it should be).

Anybody know for SURE what I should be using to remove these bolts without stripping them? Feels like it may be ~13mm....


Thanks.

 

[IBoughtASupra]

Used this.

 

[Mr Bojangles]

That's strange, I used a 10mm 6 point and it fits snug and worked great. I had to get duralast from autozone because everywhere else I checked did not have much for metric. My engine is an aristo 2J but I can't imagine the head bolts would be any different.

I wasn't to worried about damaging the bolts because I'm not reusing them, but there was no damage to any of them and they came right out with a small breaker bar.

 

[jdemara]

Weird. Mine is a 2JZ out of a Supra, and it is for sure NOT 10mm...
I have a M12 bit, which fits kinda loose.
And I have a triple square 12mm bit, which fits snug.

I might just go ahead and try a 6point 12mm then

 

[veedubin]

That's weird... my 2J (GE) had regular 6 point bolts. The replacement (OEM) are 12 point. I used a matco 12mm 12 point "triple square " ... worked great.?????

Sent from my LG-P504

 

[veedubin]

Stupid phone negate the "????"

Sent from my LG-P504

 

[Mr Bojangles]

After reading this I thought maybe I was wrong but I went out and test fit the 10mm 6 point to the bolt and it was tight and a 10mm socket slips tight on the 10mm 6 point so I don't know what the hell is going on with my shit haha. Andy, maybe this is a difference or is your motor an aristo too???

 

[IBoughtASupra]

Aristo?

Pfff.

I have a 1JZ.

Gangeles, you are saying the 10MM 6 Point Hex fits fine, correct?

I have used that tool I posted. J, post a picture of this bolt. I want see what it looks like as this sounds weird. I have used that tool to remove bolts without a problem.

 

[toyotanos]

Triple square= German cars
Bi-Hexagonal= Japanese cars

They are not the same, don't try to use them interchangably, it will not end well.

Triple square:

Bi-hex

 

[IBoughtASupra]

Triple square= German cars
Bi-Hexagonal= Japanese cars

They are not the same, don't try to use them interchangably, it will not end well.

Triple square:

Bi-hex

Yeap!

Ever seen a stripped head bolt?

:ugh:

 

[Mr Bojangles]

Here is the bolt on the 10

Here's a 10mm socket on it

Here is the 10 on the left that fits and the 12 on the right that's too big.

I have no idea why it's different.

 

[toyotanos]

the 10 is a 10mm hex, and the 12 is a 12mm hex- should be self-explanitory...

Toyota really only uses 2 sizes of head bolts- 8mm bi-hex on E-series and NZ-series engines, and 10mm bi-hex on MZ, VZ, JZ, etc engines. Can't remember what my stock 7M bolts were, iirc they were 10mm hex/bi-hex

 

[Mr Bojangles]

I think you missed some of the thread. I understand the number system, but not why my head bolts are 10mm and others are 12mm.

 

[toyotanos]

I thought you were referring to 12point vs 6 point...thats really odd. I can honestly say I've never seen that...ever.

Good thing you're ditching them for better hardware!

 

[IBoughtASupra]

Update coming to the JZ thread soon.

J, you could of had someone change the bolts before you got the motor? I know Felpro makes replacement bolts for JZ engines maybe someone was in there before you. I will contact Curt and see what he says.

 

[jdemara]

Here we go guys...
These are the results I've found!...

I have a 2JZ-GTE out of a newer Supra. Not sure if there is a difference between models though.

12mm Bi hex (12 point) fits but has wiggle room, and I wouldnt want to use this with the way it feels.
12mm triple square fits snug, but SHOULD NOT be used as it will strip the bolt.
10mm 6 point fits perfectly, and was successful at removing the stock bolts from my head without stripping.

Conclusion: Just use a 10mm 6point socket bit. Same one IBoughtASupra listed.

Here is a link to the picture again
http://img.tapatalk.com/a68989d1-735f-09f3.jpg