Barrels to engine case - sealant or gasket?

[Howard Rose]

The engine top-end rebuild is coming along nicely now, mostly
assembled and pistons attached. Also repainted the tinware :-)

When putting the barrels on, I have heard two ways to seal them to the
engine case. The first is to use the round paper gaskets (as were on
this engine before I tore it apart), whereas others recommend to use
only sealant and no gasket.

Which is the recommended way? If sealant, what type to use? I have a
tube of 'Blue Hylomar' which I have used on various things before.
Suitable?

[Speedy Jim]

Post by Howard Rose
The engine top-end rebuild is coming along nicely now, mostly
assembled and pistons attached. Also repainted the tinware :-)
When putting the barrels on, I have heard two ways to seal them to the
engine case. The first is to use the round paper gaskets (as were on
this engine before I tore it apart), whereas others recommend to use
only sealant and no gasket.
Which is the recommended way? If sealant, what type to use? I have a
tube of 'Blue Hylomar' which I have used on various things before.
Suitable?

I am all for the sealants.

Leaving out the paper may increase compression
(slightly). If that's a concern, use the paper
but smear both sides with the sealant. Belt and braces...

Speedy Jim
http://www.nls.net/mp/volks/

[Jan]

Post by Howard Rose
The engine top-end rebuild is coming along nicely now, mostly
assembled and pistons attached. Also repainted the tinware :-)
When putting the barrels on, I have heard two ways to seal them to the
engine case. The first is to use the round paper gaskets (as were on
this engine before I tore it apart), whereas others recommend to use
only sealant and no gasket.
Which is the recommended way? If sealant, what type to use? I have a
tube of 'Blue Hylomar' which I have used on various things before.
Suitable?

The paper and glue both add thickness to the sealing area, changing the
deck height. Which in turn changes the compression ratio a little.
That said, they all need to be EVEN.


I don't like using the paper gaskets, because I would use them WITH
sealant. The sealant makes them slippery, and when torquing the heads
down, they can slip out of place and cause a leak.

Blue hylomar is ok to use here, I would use just that, and follow the
instructions. I used iut myself in my early days, until I found
something better. (Mahle cylinder sealant).

Do not use Hylomar in the head side of the cylinder. You shouldn't need
anything there, if the surfaces are true and smooth. Just metal against
metal. I sometimes use that Mahle sealant there too however, a very
faint little coat.

Jan

[a***@Example.com]

Post by Jan
Do not use Hylomar in the head side of the cylinder. You shouldn't
need anything there, if the surfaces are true and smooth. Just
metal against metal. I sometimes use that Mahle sealant there too
however, a very faint little coat.
Jan

Ever spin the cylinders in the head with valve grinding compound?

better seal?
check the seal?

Mostly takes very little then ever'once in a while, "whoa, this
head's a mess". Save the crappy heads for the dune buggies. ;)

Alvin in AZ

[Jan]

Post by a***@Example.com

Post by Jan
Do not use Hylomar in the head side of the cylinder. You shouldn't
need anything there, if the surfaces are true and smooth. Just
metal against metal. I sometimes use that Mahle sealant there too
however, a very faint little coat.
Jan

Ever spin the cylinders in the head with valve grinding compound?

Yep, done that on occasion.
Mostly just use high heat, thin sealant, as little as I can.

Jan

[dave AKA vwdoc1]

I have used the valve grinding compound too which works well if needed.
Then before the tin goes back on I leakdown test each cylinder to check for
leakage at the cylinder-head seal.
I have caught a few leakers that way and use the compound to cure it! ;-)
--
later,
dave
(One out of many daves)

Post by Jan

Post by a***@Example.com

Post by Jan
Do not use Hylomar in the head side of the cylinder. You shouldn't need
anything there, if the surfaces are true and smooth. Just metal against
metal. I sometimes use that Mahle sealant there too however, a very faint
little coat.
Jan

Ever spin the cylinders in the head with valve grinding compound?

Yep, done that on occasion.
Mostly just use high heat, thin sealant, as little as I can.
Jan

[Howard Rose]

Thanks for the replies! Sealant and no gasket it is then.

I also noticed that there are some metal rings in the cylinder heads
where the barrels join. Are these standard? I can't find any
reference to them in the manual.

[Karl]

What engine do you have? Type 4's have head gaskets, but VW said to discard them and add shims to
the bottom.

Post by Howard Rose
Thanks for the replies! Sealant and no gasket it is then.
I also noticed that there are some metal rings in the cylinder heads
where the barrels join. Are these standard? I can't find any
reference to them in the manual.

[Speedy Jim]

Post by Karl
What engine do you have? Type 4's have head gaskets, but VW said to discard them and add shims to
the bottom.

Post by Howard Rose
Thanks for the replies! Sealant and no gasket it is then.
I also noticed that there are some metal rings in the cylinder heads
where the barrels join. Are these standard? I can't find any
reference to them in the manual.

There were aftermarket head rings which were
used to lower compression on Type 1 engines.

Jim

[dave AKA vwdoc1]

I thought some of the early 6 volt Type 1 engines had these cylinder to head
gaskets too? I forget though. ;-)

I remember seeing these metal gaskets being sold with the cylinder heads
from Topline about 30 years ago. The gaskets were to reduce the compression
ratio in their remanufactured heads.

Post by Speedy Jim

Post by Karl
What engine do you have? Type 4's have head gaskets, but VW said to
discard them and add shims to
the bottom.

Post by Howard Rose
Thanks for the replies! Sealant and no gasket it is then.
I also noticed that there are some metal rings in the cylinder heads
where the barrels join. Are these standard? I can't find any
reference to them in the manual.

There were aftermarket head rings which were
used to lower compression on Type 1 engines.
Jim

[Howard Rose]

Post by dave AKA vwdoc1
I thought some of the early 6 volt Type 1 engines had these cylinder to head
gaskets too? I forget though. ;-)
I remember seeing these metal gaskets being sold with the cylinder heads
from Topline about 30 years ago. The gaskets were to reduce the compression
ratio in their remanufactured heads.

Post by Speedy Jim

Post by Karl
What engine do you have? Type 4's have head gaskets, but VW said to
discard them and add shims to
the bottom.

Post by Howard Rose
Thanks for the replies! Sealant and no gasket it is then.
I also noticed that there are some metal rings in the cylinder heads
where the barrels join. Are these standard? I can't find any
reference to them in the manual.

There were aftermarket head rings which were
used to lower compression on Type 1 engines.
Jim- Hide quoted text -

- Show quoted text -

Since I'm using the same heads, I've reused the metal rings. Hope
that's okay...