Hey all,

I've changes head gaskets before, but I'm not sure if I've ever done this bit right. How long should I wait before re torquing the gasket, and what is the procedure for this? (do I have to back the studs off first or do I Just torque them up?)

Also do head gaskets need to be run in?

This is on a l20 efi, turbo, with arp head studs.

Cheers
Cam

as far as i can remember from apprenticeship days, only certain head gaskets require a re torque after xxx amount of kms. It usually says on packaging, as cliche as it sounds.

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1600 with FJ20 & Simmons. something different.

True, there are montorque gaskets that don't need retightening but it wont hurt to tighten them again.
I normally give mine another nip up once the engine has warmed up fully a few times when I go back in to adjust the valve clearances etc...

Thanks Nick,
so should I back the bolts of first or just tighten?
Cheers
Cam

I don't loosen them at all. Just tighten them up same sequence as recommended (work from the middle out and alternate sides etc)...

Thanks Nick

On my l series durapro head gasket, the packaging said not to re torque.

But I asked the guys at datsport( where I bought it).
They said to still retorque it.

So I retorqued mine using the same Method as nick.

I think the loosen off then re tighten the bolts method is used when you paint the gasket with aluminium paint.

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When the sign says "don't feed the bears", man you better not feed the bears.

thanks mate,

What about revving it hard and making boost. Is this a no no for a certain number of km's?

Only if your running in newly machined parts.
Saying that though, i'd still only run very low boost if any and keep revs to a minimum until you have retorqued the headbolts/studs and adjusted the valves etc.
Then you should be right to wind it back up to where it once was etc.
I'll be doing this on my own L20B turbo very soon as I get my new head and turbo cam back soon...

Thanks Nick,

Do you have a build thread? I'd love to have a look.

This is my method. On a cold engine, I do one bolt/stud at a time in the proper sequence. I crack them back about 45 degrees then re torque them and note if they pull down further(more than the 45 deg).

I've found that they wont pull down further when re torqueing, if they haven't been cracked first.

100% correct.

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A little knowledge is a dangerous thing.
www.datsport.com

"R.I.P. Baz. 29 April 2022. Thank you for all your contributions to the Datsun community over the years. You will be missed." - OZDAT

No build thread. I've been lazy on that side of things here on Ozdat.
That and my build started before Ozdat was around haha.
Heres a pic of my engine bay from the last Birdwood show here in SA.
I'm currently halfway through fitting the new head/turbo combo and will hopefully have it tuned and running again in the next month or so...

looks amazing mate.

Are engine internals standard?

Cheers. Its got forged pistons and an o-ringed block. Apart from that the bottom end is std L20B...