Head gasket sealant?

[friedy]

I know there's been various posts on head gaskets, but I'm getting g confused copper gasket needs sealant, wellseal or can I use aviation gasket sealer? What about Adjusa gasket does that require sealant? I'm in too minds which to use for best result.
Thanks Alan

[nmauduit]

Regarding the composite (Fiber) Ajusa head gasket, the manufacturer website advises to install them dry (unless otherwise recommended by the manual)

https://www.ajusa.es/area-tecnica

"Not assembly the same cylinder head gasket for the second time.
Not applicate over the gasket, products as greases or sealants except if it is indicated by the manual".

Caution : one may note some inconsistencies (e.g. admissible surface roughness sometimes in mm sometimes in micrometers)... this to say that the website may be a marketting tool not checked by engineers prior to publication.

All things considered, I've on occasion used wellseal on head gaskets, e.g. after some corrosion had taken place and some pitting may still remain after minimal resurfacing. Probably not a bulletproof measure, but as I would not mind the extra cleaning for the next head gasket job I coined that every little bit might help.

[SENC]

[2cams70]

Use a composite gasket and no sealant. Resist the temptation. Sealant does more harm than good. A composite gasket is already quite conformable and sealant won't do anything except make the cylinder head bolt torque less stable. More important to make sure surfaces are clean and flat.

[friedy]

Hi 2cams, that was my original thought, then I started reading too many posts, And douting my decision. Not helped by the fact I've already got a new copper gasket.

[alan.barker]

Hi Friedy,
use the copper gasket nothing wrong with that and a small lick of wellseal if it makes you feel more comfortable.
Always used copper gaskets from my first Twink back in 1974 till now no problem.
Just make sure nice clean surfaces and wipe over them with a little Acetone.
Clean out all threads in the Block for Cylinder head bolts so no Oil comes out of holes as you tighten the Bolts
Alan

[512BB]

From what I have read, composite head gaskets require a surface finish to the n'th degree as stipulated by the manufacturer.

Like Monsieur Barker, I have been using standard Payen copper head gaskets for 40 years and have never had a head gasket fail in all that time. So long as the block and head are finished to a good standard and are flat, you cannot beat a copper gasket.

Do not clean off or touch the copper gasket with ANYTHING. They have a film of something on them, put on by the manufacturer, that should NOT be removed before fitting. Indeed, there is normally a label or advice note in the packet that states this.

Leslie

[2cams70]

Note a composite gasket is a Compressed Fibre Material (CFM) one - not a Multi Layer Steel (MLS) one. Composite gaskets are relatively insensitive to surface finish unlike MLS.

[h20hamelan]

I probably shouldn’t quote this, but it seems timely. Form another chat forum about oil leaks on a Twin Cam Lotus Ford. The author is a famous chap, many refer to his paper on Weber carb tuning, many also use his parts.

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“ Here's the RTV I use on the fiber headgaskets on the Lotus TCs. On both my Elan and the 41. Otherwise I get oil seepage from the headgasket underneath the intake manifolds. But on my Elan I get a huge oil leak from the last headbolt on the exhaust side which leaks from the gasket and drips down onto the exhaust pipe. That creates smoke which makes it's way into the cockpit when I have the soft top up.

Both FelPro and Victor Reinz are aware that the gasket leaks oil and they imprint an elastic gasket material onto their fiber gaskets to try and stop that but that is not enough to stop the oil from escaping.

I smear a thin coating onto both sides and go ahead and install the head. Torque the headbolts up to 40lbs and then take the torque up to 70lbs. Then I never retorque the bolts later on. Never have had a blown fire ring or an oil leak again.
https://www.amazon.com/Permatex-81878-C ... B01LZ7WZAT

Sorry for the link to Amazon. But the Permatex website is screwed up and linked to the wrong stuff. ”

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[friedy]

Surprised at using RTV even if it is the high temperature stuff. I have the permatex aviation gasket sealer which has same temp range of wellseal so maybe I will just stick with the copper gasket and use the aviation sealer.

[512BB]

I have never used ANY dressing on a copper gasket and would not do so, as a copper gasket does not require it, so long as the mating surfaces are good. Further, there is a good chance that some dressing would be squeezed out into the pots due to the high clamping force, even if applied very carefully, and that would not be ideal.

Leslie

[joe7]

On Felpro gasket it says "use no sealer" & "no retorque required". So if using that one, there you have it. Also when we use these or other head gaskets we open up the coolant holes a bit to get better flow.

[friedy]

Thanks Leslie, I'm only going by the books and St. Miles. And I wouldn't have put the sealant right upto the fire ring I expect its more for around the water and oil ways.

Joe, isn't the felpro gasket MLS ?

Alan.

[joe7]

Search FEL-PRO 8360 PT 1, Good pic and description. Hope this helps. Also $20 USD! Never had one leak/blow except the one I took up to 7500 RPM a few times too many!! Forgot to add. In viewing the gasket, holes must be punched in the "red triangle of sealer" for coolant flow. Good idea, if you go this way, is to mate up with your head and block to ensure its a proper fit.