Tomie Head Gasket Installation

[exXU1]

Can any one shed a little light on this problem - Tomei 1.2 mm h gasket - super gromet on a RB 26/30- engine not started yet - fresh.

Every thing done right - preped and torqued corectly - but gasket weeping coolant ?

Head off - no physical signs of problem?

As stated - engine not started. Surely i can reuse this gasket - is there any type of adhesive or compound that one can use to make it seal better- or am i doing something wrong ?

Any one heard of this before as it seems strange ?

Thanks

[Craved]

when i used a metal gasket, my mechanic gave me a can of spray adhesive to use with it ...

not at home so i cant tell you what it is called, but it didn't leak.

[Malecki]

Did you get the head machined and serviced?

On the Nissan manual is says, everytime head it removed a new head gasket MUST be used

[Adriano]

Use coppercoat or hylomar in the pressure pack, just make sure the head bolts aren't stretched, and the head bolt threads are clean in the block.

Did you get the head machined and serviced?

On the Nissan manual is says, everytime head it removed a new head gasket MUST be used

[T04GTR]

just go nuts with a can of "hymolar" sp? gasket cement and go 10% tighter on the head bolts

(make sure youve got them lubed but. (molly lube on the threads and bolt head)

[Scooby]

if you've torqued it down and there is coolant weep then all the hylomar etc will do is create a seal tight enough for you to start it - maybe - and then get lots and lots of coolant weep etc. hell, if the head and block are true it should retain coolant without a gasket at all if it's torqued down. something else is badly wrong. check the bolts aren't bottoming out and the head/block are true.

[Mik]

just go nuts with a can of "hymolar" sp? gasket cement and go 10% tighter on the head bolts

(make sure youve got them lubed but. (molly lube on the threads and bolt head)

Using moly lube on standard headbolts is not a good idea. You will overstretch them if you torque them to factory specs. Just use oil.

[Craved]

Using moly lube on standard headbolts is not a good idea. You will overstretch them if you torque them to factory specs. Just use oil.

and this would do what?

i used it on my std ones, no issues here after 5000kms

[Mik]

and this would do what?

i used it on my std ones, no issues here after 5000kms

The appropriate fastener torque is selected such that it will load the fastener to an appropriate percentage of it's tensile strength. Nissan select this torque for use with 30wt oil.

If you use moly lube, the same amount of torque will result in much higher tensile load than the fastener was designed for.

This may permanently stretch the fasteners.

[burko1]

I USED A TOMEI HEAD GASKET ON MINE , AS FAR AS IM CONCERNED YOU SHOULDN'T NEED TO PUT SEALANT ON A NEW HEAD GASKET , BUT IF YOU ARE GOING TO REUSE IT , AND I WOULD THOES GASKETS AREN'T CHEAP I'D USE HYLOMAR AS PREVIOUSLY MENTIONED.

AS FOR USING MOLY LUBE IF YOUR USING HEAD STUDS THATS FINE.

BUT GETTING BACK TO IT , IF YOUR LEAKING COOLANT AND YOU HAVEN'T EVEN STARTED THE ENGINE YOU MUST HAVE A PROBLEM , I HAVE NEVER HEARD OF IT.

I HAVE HEARD OF A RB26 HEAD LEAKING COOLANT WHEN THEY ARE PORTED TOO FAR , JUST FOOD FOR THOUGHT.

Edited July 11, 2006 by burko1

[exXU1]

I USED A TOMEI HEAD GASKET ON MINE , AS FAR AS IM CONCERNED YOU SHOULDN'T NEED TO PUT SEALANT ON A NEW HEAD GASKET , BUT IF YOU ARE GOING TO REUSE IT , AND I WOULD THOES GASKETS AREN'T CHEAP I'D USE HYLOMAR AS PREVIOUSLY MENTIONED.

AS FOR USING MOLY LUBE IF YOUR USING HEAD STUDS THATS FINE.

BUT GETTING BACK TO IT , IF YOUR LEAKING COOLANT AND YOU HAVEN'T EVEN STARTED THE ENGINE YOU MUST HAVE A PROBLEM , I HAVE NEVER HEARD OF IT.

I HAVE HEARD OF A RB26 HEAD LEAKING COOLANT WHEN THEY ARE PORTED TOO FAR , JUST FOOD FOR THOUGHT.

And guess what??? Had the head pressure tested and found hole in # 3- you wouldn't read about it, the head was supposed to be a GOOD one!

Any way the problem has a remedy that is get the head repaired.

As far as the studs are concerned - ARP- i usually use minimal lube and finger tight then just a small nip as the head sldes down the studs and the nuts tighten the head down- the nut ends of the studs have moly lube on them .

I will though use the Hylomar as i will re use the gasket - but don't these Tomei super gromet style gaskets anneal once the engine is run up to temp? They look like they are ment to do something like that as they have minimal coating in them.

[burko1]

And guess what??? Had the head pressure tested and found hole in # 3- you wouldn't read about it, the head was supposed to be a GOOD one!

Any way the problem has a remedy that is get the head repaired.

As far as the studs are concerned - ARP- i usually use minimal lube and finger tight then just a small nip as the head sldes down the studs and the nuts tighten the head down- the nut ends of the studs have moly lube on them .

I will though use the Hylomar as i will re use the gasket - but don't these Tomei super gromet style gaskets anneal once the engine is run up to temp? They look like they are ment to do something like that as they have minimal coating in them.

HAVEN'T HEARD ABOUT THEM ANEALING , BUT I DON'T THINK YOU'LL HAVE A DRAMA WITH IT , ONCE IT GETS WARM WITH HYLOMAR ON IT SHE'LL BE FINE. GLAD YOU HAVE FIGURED IT OUT NOW .

Edited July 11, 2006 by burko1

[TurbostyleR]

My tomei headgasket leaks!

Im totally pissed off about it, I didnt use any coppercoat on it as i thought the black coating on the headgasket would be good enough for it to seal but i was wrong...

This is on an SR20DET motor and i have a slight leak between the head and the block on the exhaust side between cylinders 3 and 4...

I have been tempted to take the head off and clean the surfaces again and coat them with coppercoat, but i dont think you can reuse tomei gromet style headgaskets...

[Mik]

And guess what??? Had the head pressure tested and found hole in # 3- you wouldn't read about it, the head was supposed to be a GOOD one!

Any way the problem has a remedy that is get the head repaired.

As far as the studs are concerned - ARP- i usually use minimal lube and finger tight then just a small nip as the head sldes down the studs and the nuts tighten the head down- the nut ends of the studs have moly lube on them .

I will though use the Hylomar as i will re use the gasket - but don't these Tomei super gromet style gaskets anneal once the engine is run up to temp? They look like they are ment to do something like that as they have minimal coating in them.

Bugger!! I reckon you will be right to re-use the gasket since you haven't run the engine. I had to do that when I built mine because I realised that the guy who reco'd my head set the valve clearances incorrectly. (He set the intake smaller than the exhaust, like most engines).

I didn't have any issues. One thing to be careful of is that the surface grinder didn't leave to rough a finish on the head or block if you had them decked.

[burko1]

My tomei headgasket leaks!

Im totally pissed off about it, I didnt use any coppercoat on it as i thought the black coating on the headgasket would be good enough for it to seal but i was wrong...

This is on an SR20DET motor and i have a slight leak between the head and the block on the exhaust side between cylinders 3 and 4...

I have been tempted to take the head off and clean the surfaces again and coat them with coppercoat, but i dont think you can reuse tomei gromet style headgaskets...

ONCE AGAIN I WOULDN'T RE USE A TOMEI GASKET AFTER YOU HAVE HAD IT RUNNING GETTING HOT AND COLD AND ONCE IT HAS COME IN CONTACT WITH COOLANT AND OIL.

WITH TOMEI GASKET AS NEW YOU DON'T NEED TO PUT ANY TYPE OF COATING ON THEM , EITHER YOUR SURFACES WEREN'T TRUE OR DIRTY.

BUT IF IT HAS JUST BEEN TIGHTENED AND HASN'T HAD A CHANCE TO HAVE ANY PRESSURE FROM CYLINDERS OR ANY HEAT FROM THE ENGINE , I'D SAY YOU'D BE SAVE IN COATING IT AND REUSING IT.

[TurbostyleR]

nah its too late for this tomei head gasket...

stuff it ill just see how this leak keeps going, if it gets any worse then ill end up having to replace it.... :S

[exXU1]

nah its too late for this tomei head gasket...

stuff it ill just see how this leak keeps going, if it gets any worse then ill end up having to replace it.... :S

Thats a shame becauase they are expensive but having a leak is something that is hard to live with. Since your Burkos and others responses i have done a little research - as in Tomei head gasket leaking - and guess what - there is a few people who have also experienced the same thing- mine was also weeping on the exhuast side between 2 and 3 . The head and the deck are all true , but the deck is a little ruff and as one member previously mentioned that this is not the best.

I also noticed that when i had removed the gasket and did a visual inspection and between the water galeries they are all joined that is to say that they are not sealed from each other but are sealed from the oil galeries .

Is this normal as it seems strange to me - there was marks where it has tried to to seal in the water areas that i have mentioned but more none than a seal ?

[Darius]

Was the hole in your head visible? I am having the same weeping problem even after pulling the head and recoating my Cometic head gasket with coppercoat. So now I'm onto pulling the motor to have the block resurfaced (after having the head resurfaced). How many times can you install and uninstall a head gasket before its sealing ability is compromised? Same question for my ARP head bolts?

[proengines]

There is nothing wrong with the gaskets and they don't need any coating/spray/gasket goo on them. They have a fine layer of viton rubber (or similar) applied to them which is all that's needed to seal the wather and iol in conjunction with the embossing on the gasket. The main reason for leaking when they are installed on a used engine is the surface on the block is not flat or smooth. I have never milled an RB26 or SR20 block where the surface cleans up completely within less than .1mm (.004") they are always slightly low on the exhaust side and slightly pulled up around the head bolt holes. This would seal ok with a composite gasket but not an MLS gasket.

Any MLS gasket requires an Ra of 15-30 where a composite gasket requires 50-60 Ra (roughnes average) which gives a pretty good idea of what's needed, 2-4 times as smooth a finish and dead flat. Steel gaskets have very little conformability, which means they can't squash up on the high spots to seal the low spots effectively. Talk to any machine shop and they will tell you how much money they have spent retrofitting or replacing their surfacing machines to use CBN (cubic boron nitride) and PCD (poly crystaline diamond) tooling to be able to achieve these finished. Most gasket manufacturers make composite gaskets to suit engines that originally came with MLS gaskets so the head can be refitted without machining the block, it's a bandaid method but it gets cars back on the road where they would leak if an MLS gasket was refitted.

After saying all thaty, you can file the surface of a block to remove high spots but it must be done very carefully as it's easy to do a fair bit of damage if you're not careful or dont know what you're doing. One thing I'd recommend is to never fit a steel gasket without at least machining the head. If you have a head machined and you can feel the machining marks in the head it's too rough.

I wouldn't reuse a steel gasket if it was avoidable, once the embossing is flattened out there is not the preload to properly seal the water and oil. If you do reuse it, use a very good sealer. You also need to remove all the viton/nitrile coating if it is damaged. Whatever you use, none of it will seal in compression, thats a totally mechanical seal and no amount of goo will help seal it.

[TurbostyleR]

thanks proengines i am too of the opinion that the deck surfaces are too rough and its interesting to hear that the sr20s are low on the exhaust side and pull up near the headbolts...

Ill see how i go with this headgasket, if the leak gets worse then ill end up pulling the head off and sticking in a composite head gasket and seeing if that will take 30psi and ~500rwhp in an SR20 motor - as long as it doesnt knock it should be fine...

just a quick question proengines - how would you get a MLS gasket to seal properly on an SR20?