Cylinder head Gasket Sealant

[PatK]

Hi All, can you please give me your pearls of wisdom about fitting a cylinder head gasket ( alloy cylinder head to cast iron block ).  In the past I have used both Wellseal and Hylomar jointing compound. Some however say use nothing but a good gasket. From the cylinder head it looks like a brown gasket sealer has been used 30 years ago! Possibly Wellseal as its a brown colour. Since it has lasted 30 years I'm inclined towards that as a belt and braces, unless you know better. All advice will be very welcome.

Many Thanks      Pat

[poppyman]

Hi Pat, i have used both these products and they are great. Should i ever need to i always will as i have never found a cause not to, so i say use one of them.   I know i will be shot down in flames by others...... But it at least gives you a fighting chance. Wellseal was the one used when i started my apprenticeship back in the 60's.

Tony. 

[yorkshire_spam]

In my opinion nothing but a good gasket for a composite gasket, they often have a "built in" adhesive/sealant.

The only time I ever apply anything to a head gasket during fitting is if it's a metal gasket, in which case the thinnest smear of grease just to help it move and bed with the head/block.

 

[Pete Lewis]

Wellseal is recommended by triumph for the 1600 steel shim gasket all others are fitted dry 

heads pant around a lot you need the gasket to grip not have any slippery compound on its faces or it will let go 

cleaned head and block faces back to bright metal  is essential  as is  clean stud threads and decent nuts and washers are a must have  whatever car this is for 

pete

[PatK]

On 16/08/2020 at 11:07, poppyman said:

Hi Pat, i have used both these products and they are great. Should i ever need to i always will as i have never found a cause not to, so i say use one of them.   I know i will be shot down in flames by others...... But it at least gives you a fighting chance. Wellseal was the one used when i started my apprenticeship back in the 60's.

Tony. 

Thanks Tony, I have used both in the past and like you have found them to be great. So I am inclined towards hylomar as its non setting.

 

On 16/08/2020 at 11:08, yorkshire_spam said:

In my opinion nothing but a good gasket for a composite gasket, they often have a "built in" adhesive/sealant.

The only time I ever apply anything to a head gasket during fitting is if it's a metal gasket, in which case the thinnest smear of grease just to help it move and bed with the head/block.

 

 

On 16/08/2020 at 11:08, yorkshire_spam said:

In my opinion nothing but a good gasket for a composite gasket, they often have a "built in" adhesive/sealant.

The only time I ever apply anything to a head gasket during fitting is if it's a metal gasket, in which case the thinnest smear of grease just to help it move and bed with the head/block.

 

That seems to be the opinion of a lot of people, but I guess it is horses for courses. In this case it is a cast iron block, metal gasket and aluminium head. It's not he sealing of the cylinder rings as the gasket has good ridges around the cylinders, but to try and keep anti freeze from the water passages attacking the aluminium. Most of the corrosion on the 60 yr old head is from this.

[PatK]

On 16/08/2020 at 11:07, poppyman said:

Hi Pat, i have used both these products and they are great. Should i ever need to i always will as i have never found a cause not to, so i say use one of them.   I know i will be shot down in flames by others...... But it at least gives you a fighting chance. Wellseal was the one used when i started my apprenticeship back in the 60's.

Tony. 

Thanks Tony, like you I have used both of these before and found them to be very good at stopping anti freeze creeping under the metal gasket and eating into the alloy head. Most of the problems that I have had with head gaskets has been this which has led eventually to water in the oil and not loss of compression between cylinders. 

[PatK]

On 16/08/2020 at 12:42, Pete Lewis said:

Wellseal is recommended by triumph for the 1600 steel shim gasket all others are fitted dry 

heads pant around a lot you need the gasket to grip not have any slippery compound on its faces or it will let go 

cleaned head and block faces back to bright metal  is essential  as is  clean stud threads and decent nuts and washers are a must have  whatever car this is for 

pete

Thanks Pete. This engine, Jaguar Mk2, was last overhauled in 1992, and I can see traces of Wellseal on the alloy head and the metal gasket. There has been good compression and the surface between each cylinder is good, however there is some corrosion of the head face around some of the waterways where anti freeze has crept in and that is why I am inclined to using  Wellseal. I'm having the head skimmed to get rid of this pitting  and everything will be very clean on re assembly. The only problem at the moment is getting old Wellseal and parts of the old gasket off the head without scratching it as Wellseal grips like s**t to a blanket!

[Pete Lewis]

if its being skimmed wont they just remove it when milling  ???

other than that  a hard block and fine oily wet and dry can work well 

pete

takes me back to our Hunters/vogues with an alloy head and the same waterway problems of corrosion ,good that  anti freeze has improved over the years 

[Pete Lewis]

isnt wellseal  a shellac  based product so would a thinners or petrol white spirit  etc   ease its removal 

sharp scrapers can dig into the alloy so stay  ...blunt 

Pete

[poppyman]

3 hours ago, Pete Lewis said:

if its being skimmed wont they just remove it when milling  ???

other than that  a hard block and fine oily wet and dry can work well 

pete

takes me back to our Hunters/vogues with an alloy head and the same waterway problems of corrosion ,good that  anti freeze has improved over the years 

The Rootes engines were the reason I started using gasket sealant, with a preference to Hylomar. As I said before only had good results.

Tony

[JohnD]

The problem with most sealants that come in a tube is getting an evenly thin layer on the gasket.    Hylomar is available in an aerosol can, which makes it much easier:

http://hylomar.com/warrick/wp-content/uploads/2013/10/Hylomar-M-Aerosol-Issue-3.pdf

It's usually a bit more expensive than in a tube, and you waste more due to by-spray, but does esnure a most even coating.

JOhn

[Pete Lewis]

being Rootes born and bread i still wonder why i got hooked on Triumph 

some Audax convertibles are still very appealing

just found a copy of my first car   yes very red 

[Colin Lindsay]

On 18/08/2020 at 11:17, Pete Lewis said:

being Rootes born and bread i still wonder why i got hooked on Triumph 

My father had a 1962 Rootes Group Minx, it was built like a tank, and rusted like one too. The first car I looked at when I decided to buy one was a VW Beetle, I always loved those and have no idea why I never got into them as a hobby. I had Minis and various other small cars but when I decided I wanted a small fun sports car I remembered one of my brothers had had an MG Midget, and didn't want to copy him, so bought a Spitfire instead. That was the start of the slippery slope...

[PatK]

On 18/08/2020 at 09:31, Pete Lewis said:

isnt wellseal  a shellac  based product so would a thinners or petrol white spirit  etc   ease its removal 

sharp scrapers can dig into the alloy so stay  ...blunt 

Pete

Thanks Pete, I have removed most of the old gasket and Wellseal using Scotchbrite scourers ( brown ones used for paintwork ) and WD40, it works really well. I believe that Wellseal was developed by Rolls Royce and If it was good enough for them then its good enough for me.

[Pete Lewis]

it was good enough for triumph but only specd for the 1600 with its  tin   gasket 

Pete