Gasket jointing compound

[Garry ColesParticipant @garrycoles69390]

Hi, I'm just about to fit all the gaskets to my steam engine and was wondering what the best jointing gunge might be so that in the future removal will not destroy the flimsy gasket material.

Thanks

Garry

[Garry ColesParticipant @garrycoles69390]

[noel shelleyParticipant @noelshelley55608]

HYLOMAR ! The blue one ! Noel

[Russell EberhardtParticipant @russelleberhardt48058]

If the surfaces are good don't use any gunge at all. If it's really necessary try Hylomar Blue which was developed by Rolls Royce.

Russell

[HopperParticipant @hopper]

Hylomar in a spray can on the rare occasions I use "gunge" for motorbicycle assembly. Spray it thinly on each side of the gasket and let it dry before assembly.

[jon hill 3Participant @jonhill3]

I use Reinzosil on my car so I am sure it would work just as well for steam, however having a look on ebay Hylomar Blue is cheaper. I expect this is due to one being manufactured in the UK and the other costing more due to carriage and duties from Germany.

[Brian WoodParticipant @brianwood45127]

On good joints just plain translucent silicone sealing compound It was recommended in the installation instructions for flue gas sealing on the joints in the pipework on an oil boiler I installed in our previous house

My Dad made up a head gasket for a 2 stroke Atco lawnmower many many years ago using brown paper, it was an old motor bike trick of the time

Regards Brian

[Oily RagParticipant @oilyrag]

+1 for Hylomar and as an alternative Wellseal. Wellseal is made by Kommerling UK, it is used for sealing dry cylinder liners so is adept at both oil, water and gas. You can also use it without gaskets in a metal to metal method as in fact Hylomar can be used. Both are non-setting and 'peelable' on disassembly.

Martin

[Grindstone CowboyParticipant @grindstonecowboy]

+1 for Wellseal, but it's messy stuff, use gloves if you can.

Rob

[not done it yetParticipant @notdoneityet]

I used Wellseal on the crankcase halves of my Honda motorcycle engine back in the 1960s – no gaskets on them. Never leaked.

[Garry ColesParticipant @garrycoles69390]

Many thanks for all your answers. I have some old Wellseal that I used on my Nortons but didn't think about using it on my steam joint gaskets.

[Oily RagParticipant @oilyrag]

Garry,

If it has gone a little 'tacky' with age (don't we all! ) you can thin it with perchchloroethylene.

[Bob RodgersonParticipant @bobrodgerson97362]

+another one for Wellseal.

[Garry ColesParticipant @garrycoles69390]

Never heard of this stuff perchchloroethylene.

[Grindstone CowboyParticipant @grindstonecowboy]

AKA dry-cleaning fluid or spot remover

Rob

[Oily RagParticipant @oilyrag]

Sorry, too many Ch's in there I got disturbed by Mrs Rag when typing the comment, it should have been perchloroetylene. From Wikipedia:-

Perchloroethylene, also known as perc, is a colorless, nonflammable liquid solvent with a sweet, ether-like odor. It is primarily used in industrial settings and also for dry-cleaning fabrics and degreasing metals.

So pop down to your local dry cleaners for a lemonade bottle full! Probably 'trike' would do (if you can get any) – it is still available but not easy to obtain.

Martin

[J HancockParticipant @jhancock95746]

IF you want to have problems forever, I recommend using Blue Hylomar on fuel system joints where petrol

is concerned.

It is worse than useless and swells up , falls off and blocks jets for years to come.

NEVER use it.

[Oily RagParticipant @oilyrag]

You should never use ANY sealant on any fuel injection system. The connections are all 'dry seal' type and are designed not to need any sealant – just the taper seals between components. Where the odd use of a flat face seal is required the usual recourse is to use an annealed copper washer or a 'Dowty' – aluminium with o ring washer. Again never reuse old copper washers unless you re-anneal them. Dowtys should always be replaced.

This applies to all liquid fuels such as diesel, gasoline and alcohols. Gas systems in many cases also use, in general, a 'dry seal' system.

Martin

[Howard LewisParticipant @howardlewis46836]

Hylomar!

Wellseal was also developed by Rolls-Royce.

We used it to seal the wet liners to the cylinder block on the C Range engines.

Smelly, and it seemed that the only solvent to get off hands or overalls was trichlorethylene, in those days. (Now banned! )

A thin bead of silicone can be used . It effectively acts as a gap filler on what is otherwise a metal to metal joint.

Use it sparingly. There have been cases where excess has squeezed out and blocked the very passage it was supposed to keep leak free!

Where fuel systems have conical joints, as Oilyrag says NO sealant. Manufacturers have put vast amounts of effort into developing joints that will withstand suddenly applied pressures of more than 1,500 bar.

Howard

[J HancockParticipant @jhancock95746]

Far too long ago to remember now but I would 'love' to know if that 'non-recommendation' was on the Blue Hylomar instructions for use ?

You are right , no sealant , just the gasket .

[J HancockParticipant @jhancock95746]

Far too long ago to remember now but I would 'love' to know if that 'non-recommendation' was on the Blue Hylomar instructions for use ?

You are right , no sealant , just the gasket .

[Phil PParticipant @philp]

It is not advisable use silicone sealant on your Austin 7 head gasket, that is if you ever intend to remove the head again.

Dont ask me how I know !!

I only use two types of sealants for most jobs these days, Blue Hylomar and Wellseal.

phil

[Russell EberhardtParticipant @russelleberhardt48058]

Posted by Phil P on 19/03/2021 10:22:35:

It is not advisable use silicone sealant on your Austin 7 head gasket, that is if you ever intend to remove the head again.

Agreed, I used to just give the gasket a thin smear of grease. It made head removal easier for the frequent de-coke!

Russell

[Howard LewisParticipant @howardlewis46836]

If the gasket material is flimsy, almost any sealer applied to it will result in damage when removed, most certainly the "stickier" varieties. A brown paper gasket is likely to rip even if grease was used to hold it place while the mating part was fitted.

High torques on fixings of pressed steel components can cause soft joints, coated with Hylomar to be extruded..

It is difficult to disassemble soft joints, without some damage, once they have been subjected to sufficient clamping force. Cylinder Head nuts and studs, or bolts produce quite large clamp loads.

A screw thread gives a tremendous mechanical advantage to apply an axial load.

Think how long one turn of thread is, to give a lift of one pitch. 1/4" x 26 tpi gives a mechanical advantage of 20:1. Quite a long crowbar!, to which a force is then applied.

.As an example, a 1/2 UNF bolt in W range tightened just into yield exerts a 9 Ton clamp load!

And overtightening can bend even a deep casting, worsening leakage rather than curing it.

1/4 BSF can crack a Myford Cross Slide, as I know to my cost.

Howard

[noel shelleyParticipant @noelshelley55608]

Many manufacturers specify NO compound ! I have had it where the compound acts as a lubricant and allows the gasket to slide and be displaced. Dry it will be held by the metal surfaces and stay put ! Heldtite is still made, another old type gasket sealer, I think spirit bases. Noel.

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