Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

standard head gasket vs copper

cohn

VN28CN
Joined
Nov 30, 2004
Messages
228
Reaction score
1
Points
0
Location
Penrith
Members Ride
VN Calais Turbo
I have a RB30ET which i just rebuuilt the motor on replacing the original gasket with a copper head gasket and it is mixing oil with coolant in the motor so i am saying it's leaking through the head gasket.
I followed the torque specs in the gregories book, is this only suspose to be for the standard gaskets, is there a different torque spec/ sequence for a copper head gasket?
Does anyone know the exact procedure and specs for each gasket?
What is the boost limits for each gasket?
I will be running 1 bar or 14.7 psi of boost.

Thanks.
Colin.
 

mag

Member
Joined
Jun 23, 2005
Messages
869
Reaction score
12
Points
18
Age
58
Location
South OZ Adelaide
Members Ride
VY Series 1 Acclaim 2003
I have a RB30ET which i just rebuuilt the motor on replacing the original gasket with a copper head gasket and it is mixing oil with coolant in the motor so i am saying it's leaking through the head gasket.
I followed the torque specs in the gregories book, is this only suspose to be for the standard gaskets, is there a different torque spec/ sequence for a copper head gasket?
Does anyone know the exact procedure and specs for each gasket?
What is the boost limits for each gasket?
I will be running 1 bar or 14.7 psi of boost.

Thanks.
Colin.
What no one knows..:whistling
 

Daza

Member
Joined
Jun 13, 2005
Messages
105
Reaction score
2
Points
18
Age
55
Members Ride
VZ SS
I cant help you with the boost limits of the different gaskets, but you would normally only use a copper gasket if you were removing the head often or just couldnt get the original gasket.
Did you use anything on the gasket faces?
Does the head block face use any O ring type seals? (Im not familiar with this motor)
Did the head pressure test OK? It may have an internal leak from one of the oil galleries.
I have found a liberal spray of "Hylomar" it helps them stick/seal a lot better. If it's a new copper gasket retension it after the first heat cycle (I normally do it when it's hot radiator cap never fitted). Then retension at 500km's that should do it. Use the reccomended tension and sequence as the bolts and decks are normally the limiting factor. You can use other stuff as long as its not in contact with the flame front normally only around oil/water galleries (Avation gasket cement 4 this will make the head difficult to remove though). Back in the stone age silver frost paint was also used on gasket faces.
Good Luck
Daza
 

ucwepn

America just kicked in yo
Joined
May 19, 2005
Messages
2,472
Reaction score
16
Points
38
Location
Melbourne
Website
www.darkcold.com
Members Ride
WH statesman 5.7
Copper head gaskets are generally used on higher compression motors to lower the compression so that more boost can be run I.E- non turbo to turbo conversions. Are you sure its not a steel gasket? You should get in touch with a good performance shop that has experience with rb30's and they will know whats up with the tensioning for different material gaskets etc.
 

Bax

Projecting
Joined
Jan 9, 2004
Messages
3,502
Reaction score
36
Points
0
Age
37
Location
QLD
Members Ride
Nothing
I'd say that 99 out of 100 people will recommend you the genuine Nissan gasket, I'm fairly sure I told you this in the original thread that you created. And I stand by it.

However, as far as your gasket goes, as has been said above a liberal coating of another gasket putty/ sealant along with the gasket should get yourself a good seal. As far as doing the bolts up the sequence will always be the same, its that way to get equal pressure across all parts of the head.

Did you re-torque the bolts after 500 km's or so? Every gasket is meant to shrink a bit with heat, once it has reduced you are meant to re-torque all the bolts to take up the slack from the reduction in size, same goes for exhaust and inlet manifold gaskets.
 

Tree cutter

Tree cutter
Joined
Apr 15, 2006
Messages
1,020
Reaction score
8
Points
38
Location
Mt Gambier SA
Members Ride
VX Calais SuperchargedV6
Are you sure it is a gasket problem and not a cracked head. RB30 heads have been known to crack from front to rear along the camshaft bearing journals. You might have a small crack that is hard to see.
 

cohn

VN28CN
Joined
Nov 30, 2004
Messages
228
Reaction score
1
Points
0
Location
Penrith
Members Ride
VN Calais Turbo
the head had a crack but thats been fixed when i did the head, and its been cracked tested.
re-torque? do you mean just go over the bolts, or loosen then tighten again, and hot or cold motor?
 

Bax

Projecting
Joined
Jan 9, 2004
Messages
3,502
Reaction score
36
Points
0
Age
37
Location
QLD
Members Ride
Nothing
re-torque, you'd have to tighten them again, as far as hot/cold motor goes i'm not sure, presumably cold but you'd have to ask your mechanic or somebody local about that.
 

Daza

Member
Joined
Jun 13, 2005
Messages
105
Reaction score
2
Points
18
Age
55
Members Ride
VZ SS
Im my experience with copper head gaskets they expand a little and anneal on the first heat cycle thats why I retension them when hot on the first cycle. In my opinion they are not ideal for anything with a iron alloy face as the expansion rates differ to much. If you are using the copper to get a thicker gasket to decompress thats allways a risk.
Hylomar when applied correctly is good gear, I defy anyone to fit a head gasket to a 265 and seal it without using this stuff.
Cheers
Daza
 

BLOWN-VP

New Member
Joined
Nov 4, 2005
Messages
32
Reaction score
1
Points
0
Age
54
Location
beaudesert
Members Ride
vpv6auto
some copper head gaskets are already annealed heat cycled when you buy them.on my blown vp i used three bond sealant on the copper head gaskets.also heads are o ringed.tightened standard head bolts to factory specs.loosened slightly and re tightened.no problems.running 10 psi boost whipple charger.
cheers darren.
 
Top