2JZ Head Gasket Question...

[jdemara]

So Im posting on behalf of a guy I know at work doing a 2JZ swap into his lexus..

He had his head machined, cleaned the block surface, and got a new stock 2j head gasket. Used a light coat of copper spray and torqued it all down. Then realized he forgot to put the dowel pins back in.

I told him it IS necessary to have those in place, but he is now wondering if he can simply just pull off the head again (i mentioned it is important to loosen them in proper sequence), install the dowel pins, drop the head back on and torque up the arp studs without machining the head again. (the engine hasnt even been run yet)

He hasnt had much luck finding an answer as of yet, any suggestions I can pass on?

Thanks

 

[IJ.]

Why did he use copper spray on a new gasket?

If he lifts the head he's going to need to strip any and all coatings then respray with copper on reassembly.

 

[jdemara]

He was under the impression a light coat is a good idea but still not necessary.

So basically as long as the surfaces are cleaned again and dry, he'll be fine. Even when the head is Loosened in the proper sequence, no worries of warpage.

 

[IJ.]

Remember it's going to be reversed sequence to undo it and don't undo each bolt all the way in one go do it in steps say 1/2 a turn then the next bolt and so on repeating until it's done, haven't seen one in person but I "believe" the OEM gasket is Viton coated, the Copper reacts with it (well the thinner used in the spray can does)

JDub wrote an article on this it's stickied in Tech.

 

[jdemara]

So 100% of the copper spray needs to be removed from the head gasket in order for it to seal? Or will it still seal if there is tacky copper spray on it?

 

[IJ.]

When he lifts the head most times it will peel/damage some of the OEM coating so he's going to need to seperate the layers remove ALL of the OEM coating the tack spray it all with copper and reassemble.

 

[hvyman]

Coating will most likely stick to both head and block.

To re use properly need to take all the layers apart clean all the Viton off spray each side with copper spray and reassemble in the same order it was taken apart.

It's some work and might be easier to just get another gasket.

Edit: damn got beat by seconds.

 

[IJ.]

Hahaaa

 

[Mr Bojangles]

lol me too, nevermind

 

[hvyman]

Lol.

 

[IJ.]

Win for the Old Guy!
(started typing that 2 days ago)

 

[jdemara]

lol!
this is interesting for me, learn from others mistakes
alright well he said there is copper stuck to the head and the block that he has cleaned off, but no black was on the head or block. does this mean the viton coating is still one with the gasket? Or like you guys said, regardless, needs to be taken completely apart and each surface has to be perfect on the gasket?

"will it seal OK if the copper coating is just left on the gasket and re-installed?" was his main question.

 

[CyFi6]

I did this with my 7m a while back. Had to take the head back off before the thing ever ran. I decided to save a few brain cells (acetone is some nasty stuff) and buy a new gasket.