Best MLS head gasket to use.

[KEMP]

I am finally getting a start back on my 240,

the cometic did not seal for me.

so i plan to do a Greddy, does anyone have any feelings on this, or a different brand to go with, or should i just do the greddy,

i plan to do the 1.4mm thick, instead

[meminto]

What was the cause of the gasket not sealing properly?

[MeanGreenS13]

same as it always is probably with a cometic, Improper machine work and installation. (nothing meant towards Kemp) cometics do seal, ask dee. You just gotta do it right.

[boost_boy]

No matter what anyone says, I find it kind of hard to believe that this company is making defective headgaskets. It has a lot to do with the way most of you are torqueing the head and more than likely surface preparation. Just because a machine shop say that decked your block and milled your head true, doesn't mean that's the case. If it makes any sense to you guys, I've used cometic gaskets I've bought off members from this forum on CA18s that had not been to a machine shop and no copper spray as well.

I'm not that special and neither is the engines I work on nor the gaskets I use. It's just that some of you rush and you don't don't listen which ultimately lead to your failures. Unless your block or head is cracked, these gaskets do the same as all the others. I ought to know because I have NISMO MLS gaskets as well and have sold many of them in the past and by comparison, looks like the same crap to me.

So in closing, there's no better MLS headgasket, but the user/installer can do a better job at installing them . Good luck..............

Dee

[KEMP]

so, what do you suggest me doing?

it was leaking out of the back like many people have had problems with.

i always torque to 30, loosen, torque to 55, loosen, and then torque to 86-90.

in the correct sequence as stated by the FSM.

the hed is going to a performance machine shop, and will be true. the block was decked before, but the car has not over heated or even came close since that. is there any way the block could be not true?

what do you recomend.

[sjbsuperman1425]

FSM head torque specs:Tighten to 22 ft-lbTigthen to 76 ft-lbLoosen all completelyTighten to 22 ft-lbTighten to 76 ft-lb OR if an angle wrench is avaible, tighten 85 to 90 degrees clockwise.

notice the bold statement. it was one thing that was stressed in one of my college courses. also, take a straight edge and a feeler gauge and check the head and block surfaces yourself.

[KEMP]

i dont have an angle wrench, nor have i used one.

[sjbsuperman1425]

im just suggesting things. from the FSM it states to torque it down to 76 ft-lb OR 85-90 degrees, not 85-90 ft lb.

i'd still double check the surfaces with a straight edge and feeler gauge when you get it back.

[KEMP]

yeah, but i was told the cometics/mls gaskets were to be torqued to 86

[mbmbmb23]

Torque plates? Anyone use one when milling their block?

[r34 gtr]

It needs to be flat as f***. I plasi gauged the head/block surface by torquing down the head to the block, and it was less than 2 thou out in the worst spot, and even my stock gasket leaked.

Not leaked as in didn't seal properly, but leaked as in it dribbled a little bit of oil down the back by the #4 exhaust port. Any leak is unacceptable to me, so out it comes.

[boost_boy]

so, what do you suggest me doing?

it was leaking out of the back like many people have had problems with.

i always torque to 30, loosen, torque to 55, loosen, and then torque to 86-90.

in the correct sequence as stated by the FSM.

the hed is going to a performance machine shop, and will be true. the block was decked before, but the car has not over heated or even came close since that. is there any way the block could be not true?

what do you recomend.

Listen to me folks and listen real good. The #7 and 10 headbolts are tricky because the nissan casting on the head is a bit excessive to fit a standard 10mm hex socket. What's happening to most of you is that the drag on the hex socket causes an inaccurate reading on your torque wrench which subsequently will leave the #7 and #10 headbolts not completely torqued which in turns causes you guys' leaking.

If this doesn't pertain to you and you are sure you've done everything right, then you may want to go back to a composite gasket. I can only go off what you guys post on this forum. I have no idea what you are actually doing, but it's kind of ridiculous that people are having the same problem from cometic's metal h/g.

Dee

[sjbsuperman1425]

Dee,so basically what you are saying is that when torqueing the headbolts, the bolt itself isn't pushing the head to the block, but the torque wrench is hitting the maximum torque that it is set too because of the headbolt "dragging" correct?

[mazikowski]

What I think he's getting at is the fact that the socket 'binds' and trips the torque wrench.

[float_6969]

Yes, it's makes the torque wrench read falsely high.

I have NEVER found a socket that works w/o touching. I finally bought a cheap 12point and took it to the grinder until it didn't touch on any of the bolt holes. There is NOT a lot of material left, and it looks scary, but I've used it a zillion times w/o any problems.

[MeanGreenS13]

i had my head machined to fit my socket down in there properly, and ive never had a tq issue, just a sealing issue due to imporper mating surfaces and the fact that the head was off .006

[boost_boy]

I was sleep when I posted my hypothesis to this issue, but it is now corrected .

Dee

[sjbsuperman1425]

i have a question..

isn't there a specific RA (arithmetic average roughness) on the block and head? like 60-100 RA on the block and 50-60 RA on the head?

[sjbsuperman1425]

i had my head machined to fit my socket down in there properly, and ive never had a tq issue, just a sealing issue due to imporper mating surfaces and the fact that the head was off .006

thats a good idea, i'll have to remember that.

[RS12Turbo]

Off topic...but I am getting ready to put on a Cometic mls gasket, and am curious if re-using the oe head bolts is ok, or if arp's are recommended

[r34 gtr]

I used to have a totally sweet Snap On socket that seemed to have been made for the specific purpose of removing the CA18 ARP head bolts. Then it disappeared. I cried.

I usually torque the head down sans cams. It gives you a lot more room to work with.

[boost_boy]

Off topic...but I am getting ready to put on a Cometic mls gasket, and am curious if re-using the oe head bolts is ok, or if arp's are recommended

No re-using OE headbolts. They stretch and you will be disappointed. You can just replace them with a new set of stock bolts if you want or use the ARP stuff.

Dee

[zero_gripS13]

i was told the requirements is 20 ra for the block.. my heads looks like glass and my block is ment to meet the rquirements of a cometic but i only have a used cometic, (was bolted down one time never ran, im skeptical to try it, i think ima just use my felpro.... it should be fine for up to 350hp.

[meminto]

The RA needs to be the same grade on each surface...

You could file the block for squareness, but I would safely assume most people wouldn't, I didn't on my last build....

The manufacturer of the headgasket will probably specify the RA grade...

[dash]

mazworx take on cometicshttp://www.sxoc.com/vbb/showpo...unt=5http://w ... unt=7Gotta be somethin goin on

[nismoplsr]

I cant say anything about Cometic but i have had no problems with my 1.2mm Trust(Greddy). I use with ARP studs, copper spray and the snap-on 13mm 12 point socket to torque them down. No leaks and i am on my second use, running 22lbs of boost.

[slw240sx]

thats because they have designed and manufactured a gasket with another retailer and want to sell them.

I have used dozens of cometic's and only one leaked, and that was a machining error and customer that couldn't see that his front cover of a KA was way off compared to his deck.

frank, if you go to composite let me get that MLS off you!!

Jon

mazworx take on cometicshttp://www.sxoc.com/vbb/showpo...unt=5http://w ... unt=7Gotta be somethin goin on

[dash]

If other SR20 installs were having problems it'd definitely show up on the forumso Mazworx would stoop to that level just to "push" a what? $80 gasket ?

Still doesn't explain why about half the cometics leak on sxoc & nico CA18s.A few CA18s claimed cometic held fine with no machining to either surface.

I was wondeing if eliminating the stock sturdy intake brace had any relevance to head gasket seal durability. I can't see why nissan would go thru all that effort for such a heavy duty part for nothing. Oems r cheap bastards

[r34 gtr]

^ that is an interesting thought, as most people DO have leaking issues at the #4, which is where it would try and pivot if one removed the brace. Not that the intake manifold weighs anything though.

[KEMP]

i highly doubt that bracket would do anything HG related, you gotta remember, the head studs are pulling the head down with around 80ft-lbs, the brace has no where near that much force pulling down on the intake manifold, and if this were true, wouldnt you need another brace holing the exhaust manifold to equal pressure from intake to exhaust sides?

all in all, that would never cross my mind, and should not be a concern as to why it leaks.