Gaskets

Why do we need gaskets?

Gaskets serve the purpose of sealing, there are three main sealing tasks on almost any engine:

• Oil Seals - a low (or no) pressure seal designed only to retain oil within the sealed area. Used on such things as an access panel. Oil seals are usually paper, cork, felt, or vinyl.
• Manifold Seals - a seal designed to provide a tight seal between an inlet or outlet manifold and the cylinder head (or engine block in some cases). This seal is gas tight and heat resistant, but is not designed to withstand high pressure. Manifold seals are usually asbestos, paper impregnated with asbestos, or some other insulative material which does not ablate under great heat.
• Pressure Seals - a seal designed to provide a gas tight and pressure resistive seal, often keeping the combustion pressures and cooling water pressures apart. An example of this seal is the head gasket. Pressure Seals are usually made out of soft metal (such as copper or aluminium), asbestos sheet, or a mixture of both such as a sandwich of copper/asbestos/copper or asbestos/aluminium/asbestos.

My gasket could be made of asbestos? Is it dangerous?

Modern asbestos gasket material is different to that used in the past in that the fibres are bonded within a matt of some other material such as paper. This form of asbestos is still considered dangerous to work with and must be treated with care.

It is not the place of this article to define safe handling for asbestos, and I strongly urge the reader to contact the retailer or manufacturer of the asbestos product you are planning to use and adhere to their safety guidelines. I will not go into safe handling procedures here due to the legal ramifications.

Your local government may have regulations for the disposal of asbestos, these rules are for the good of all of us, please find out what they are and adhere to them. For example, in my area of Melbourne asbestos may be disposed of by wrapping it in heavy plastic, sealing it with tape, and calling the local council waste department who will arrange either collection or somewhere to drop it off. Please don't just throw it in the rubbish - consider the people who have to handle your garbage.

I've stripped down my engine, and need to replace or refurbish my gaskets - what do I do?

Metal/Asbestos sandwich gaskets

From: Allan Johnson ajohnson@dove.net.au
Re used copper/asbestos gaskets i have had some success in reusing them. i place the gasket in a shallow container in about an inch ( showing my age here) of water. sit it on a gas ring & boil the heck out of it, for 30 minutes topping up the water as required. In some cases this will expand the asbestos. let the gasket dry out, and away you go. Worth a try if the copper is in reasonable nick. regards, Alan Johnson Naracoorte South Australia

From Ted Lee
My IBC-ESCA book (1975) ( since been taken over by Dunlop & at the present time goes under the banner of AEBaker.) lists Payen gasket sets for 2,3,4,& 6 HP Rosebery Numbers 1S317, 1S317A, 1S318, & 1S319. If there is no AEBaker near you then the best bet is to find an old established engine re-conditioner and ask if the Payen gasket sets are still produced. We used to be able to buy material called Klingerite, Asbestos sheet reinforced with steel wire mesh, there must be an alternative on the market but the problem is to buy a 6 inch square bit of it. Then again an end user is the best bet, an old established engine re-conditioner or boiler repairer, handyman at the Dry Cleaners may have a piece left over after cutting the centre out of a hole. The Brisbane Yellow Pages lists several gasket material suppliers including one from Richard Klinger himself. Queensland Gaskets have Blue Max boiler gaskets, www.queenslandgaskets.com.au e-mail queenslandgaskets@lbm.net Have a look under your kitchen sink, lurking in there you may find an asbestos gizmo for standing pots on to stop the contents from burning on the bottom, it's only ever been used once & now it is hiding in there, that would make a great gasket except that it may be too soft with no reinforcing.

Metal only gaskets - copper

To reuse a copper gasket which has become hardened simply heat the entire gasket evenly to cherry red and immerse it in cold water. This has the affect of making the copper gasket soft again.

Metal only gaskets - not copper

What can I use to make an Oil Seal Gasket?

From: Roland Craven rc9076@eclipse.co.uk
For low pressure low temperature gaskets thick envelopes or cereal packets are cheap and effective.

What can I use to make a Manifold Seal Gasket

What can I use to make a Pressure Seal Gasket

Ok, so I've got my material, so how do I make the gasket

You can also place your gasket material against the part in question, and using a ball-peen plumbers hammer gently tap out the shape of the holes within the part into the gasket. You must take great care when doing this so as not to damage the part you are trying to seal.

From: Roland Craven rc9076@eclipse.co.uk
Marking out can be done using Prussian or Engineers blue. Smear lightly on the surface of the part and then apply even pressure all over the paper whilst holding in-place on the part. On thin paper a dirty finger rubbed over the profile works as well or better. (Ed: charcoal sticks or a wax crayon would also work to make a tracing)

For making paper and asbestos gaskets a set of hole punches is very useful and should be used over a lead block to save the punches cutting edge. For larger holes a set of tank cutters is also very useful but expensive.

From: MaytagTwin@aol.com
I like your gasket advice, and I noticed you included the ball peen hammer method of laying out the gasket to fit a casting. I have found a light hammer and many light strokes works best to make a good outline of where to cut the gasket to fit, although I have seen some folks whale away with the hammer, using the sharp edges of the casting to do the cutting of the gasket.

One thing I have done, and find sometimes helpful in objects such as engine heads that have bolt holes going right through, is to lay the head on top the gasket paper and spray a little paint through the bolt holes, marking where you need to cut out. That takes care of the alignment of all the bolts and then you can hold the gasket in place on the block with the bolts to steady it while ball peening around the cylinder cutout.

From Ted Lee - Making your own copper sandwich gasket
Failing all that make your own sandwich gasket, obtain a couple of pieces of thin copper from a craft supplier, a tin of Hylomar spray sealer from Repco, some fibre glass matting from a body shop, & 2 pieces of plywood about 10 or 12 mm thick. Carefully place one sheet of copper over the gasket face & tap around it with a small balled hammer to mark the cutout, carefully cut this out about 2 mm larger all around. Use this to mark the other copper sheet, the glass sheet & both plywood pieces. cutout the glass sheet & one ply piece exactly on the line, cutout the second copper piece 4 or 5 mm smaller all around, & the second ply about 10 mm larger. Now lay the second copper piece on the first Ply piece ( if this is an irregular shape you will have to think about which side of the ply to use) using a round bar ( socket spanner extension) tap the copper through the ply until it is flanged evenly all around, turn the copper over so the flange is up, spray it and the glass with Hylomar, place the glass over the flange then spray it and the first copper piece with Hylomar, place the first copper piece over the flange, now place the second ply piece over the lot and clamp it all together. now carefully tap the flange down over the other copper piece. All thats left to do now is drill the bolt & water holes, use a piece of paper or cardboard to transfer the holes to the ply then drill right through the ply and all, trim up the outside and there you have it a brand new copper sandwich gasket, use Hylomar both sides of this when final fitting it.

Fitting the gasket

Fitting the gasket using Loc-Tite 515 Gasket Sealer

UPDATE Two other sealing methods have been brought to my attention which are useful in that they do not glue the gasket to the surfaces making them much easier to remove later. The first is to use a thin coating of ordinary grease on both sides of the gasket. The second is to use a thin coating of liquid soap.

Fitting with liquid soap - John Hammink

Fitting gaskets with grease - Edd Payne

Fitting gaskets with grease - another testimonial - Bill Brueck

Fitting the gaskets dry - Joe Kelley

Who supplies gasket material or ready-made gaskets?

There are also several dedicated suppliers of materials (including ready-made) such as:

• Vintage Engine Spares in Queensland
• F.A. Maker P/L in Altona, Melbourne, Victoria
• Automotive Surplus in Mitcham, Melbourne, Victoria
• Repco just about everywhere
• Bevic Auto Parts

Some example gaskets

The rectangle gasket is an oil seal gasket for the access door into the crankcase of the same engine. It is made of thick oil seal paper. This gasket can handle minor pressure but not heat.

The small fuzzy looking white ring is the gasket which seals the crankshaft where it passes through the main bearings in the block. This gasket is made of felt and is another oil seal gasket. This gasket can handle only oil not pressure or heat.

The rombhoid with several round holes is a manifold gasket which seals the exhaust outlet and fuel mixture inlet ports. It is made from asbestos and graphite and can handle some pressure and extreme heat as well as resisting petrol.

Reusing Copper Gaskets

Subject: Re: reusing Copper Gaskets & other gasket experiences
Date: Wed, 15 Nov 2000 02:22:04 -0000
From: "Joe Prindle" 

To re-use your copper gaskets, heat it up with your propane torch and quench
it in water to anneal it. Copper and copper based alloys (brass, etc.) are
the only metal we commonly encounter (at least that i am aware of) that you
quench to anneal. Annealing it makes it soft so it can conform to the
irregularities of the gasket surface and help seal it up. It is wise to use
the Permatex Copper Coat gasket sealant, as Kelly has mentioned. I,
personally, prefer the stuff that comes in the can with the brush in the
cap. I get mine at Carquest auto parts houses. It is also available in the
aerosol can, but I could never figure out why anyone would use it that way!
It must make a tremendous mess. This stuff is different than the gold
silicone RTV that I see at Wal-mart. That product is pretty handy, too. I
use it on the copper o-rings that seal up the transfer valve on the Reid
engines. I also used it on a 20 hp Otto a while back that had a tendency to
blow head gaskets. I made a new gasket from 1/8" thick asbestos and soaked
it in water overnight, gobbered some silicone on the gasket surfaces of the
engine and then installed the head and got out the slug wrenches and brought
the nuts done fairly aggressively, but evenly. I am adding this because I
read a while back about someone who had a big engine that was not retaining
it's head gasket and thought this might help. Most guys don't soak the
gasket or use too thin a gasket material and, while you usually get by, it
can bite you once in a while. I don't remember who it was, so if you read
this, contact me if you need some thick asbestos. I still have a little I
can spare. Some big engines, like the 16 hp Jones and the 20 hp Evans, only
have 4 studs holding this huge head in place and it can be a real bear to
get them to seal up good and stay that way. I got a hold of a product called
"tite-seal" and have used that  to seal 'em up. The product is used a lot to
seal up flange gaskets on steam lines and the like. Another product for
stubborn leaks in called "lincote", it is linseed oil that has been triple
boiled and is nasty, sticky stuff. It is what we use at work to seal the
halves of the casing on our old steam turbines. In our application, we use
no gasket, just Lincote, and it usually works. The front half of the turbine
has 400# of pressure on it and is 750 degrees Fahrenheit, the back half has
a vacuum of about 29"hg pulled on it and runs about 90 degrees Fahrenheit.
It is all one big semi-steel casting, 3" thick and the thermal growth from
room temperature to operating temperature is about 5/16" from one end of the
machine to the other. The best part is that the machine was built in 1926
and is still in good shape. I am telling all this because it shows how well
this stuff works, and I thought someone may find it interesting. Am I the
only one on the list that makes kilowatts out of b.t.u.'s? just curious.
Most gas engine cylinder heads and valve cages were faced on a lathe and
most lathes, then or now, do not face surfaces perfectly flat, but rather
slightly concave. If you don't believe me, take a facing cut 6 or 8 inches
in "diameter" and blue it on a surface plate. You will find it as much as
.0005 per inch concave. So what you wind up with is a head that bears harder
against the outer edge of the block than it does next to the cylinder. This
means the gasket is clamped tighter on the edges than it is in the center,
in fact this is the reason why you need a gasket. On little engines, it
usually isn't a big deal. On larger ones, these things tend to show up more,
particularly if you work the thing hard so as to push the pressures up a bit
in the cylinder. To that, add the stresses that show up in the casting from
the heating and cooling cycles, and the stresses that show up as time
passes, and there are just some engines that don't like to hold a gasket. I
have had real good luck with a thick gasket and lincote or RTV. I prefer the
Lincote, but am getting low and don't want to buy a whole gallon of it and
watch the can slowly rust through! We had a big 14hp Waterloo Boy when I was
a lad. Grandpa busted up hundreds of engines and tractors from '38-'43, and
bought a pair of these Waterloo's. This one was in good shape, so he kept
it. Anyway, when I got interested in collecting, we pulled it out of the
rhubarb patch and got it going. We used it on a little Blizzard silo filler
and on a little hand feed thresher. We were plagued with head gasket
troubles. If we worked it real hard, it would start blowing bubbles in the
water hopper. Gramps and Pa pulled the head and it wasn't flat, at all. It
had never been frost damaged or welded, but it was about .020 low in the
center, so they turned it and took just enough of a facing cut to clean it
up and put it back together with a good gasket and some LinCote and it never
gave trouble again. Gramps told a lot of stories about busting up tractors
and engines. He said the crankshaft on a titan 10-20 was a lot easier to
handle in pieces so they would dump a chunk of axle shaft into the crankcase
while the engine was running to break it in half. He also talked of standing
on the pulley side of Oil Pulls while they were running and shoving a piece
of axle shaft through the spokes of the flywheel while it was running,
making many smaller pieces, easier to handle. He liked the old iron, but it
was common then and at first it was a way to earn a living when things were
tough, later it was a patriotic duty to recover scrap for the war effort. I
have a flywheel from an oil pull laying out behind the shop with all the
spokes busted out of the rim, and several lubricators and mags for early
tractors, he saved those things because they were things folks who were
still using the tractors could use. My Ma has a picture of Gramps and his Pa
on a Tractor built out of a big Foos on a Morton truck. They bought it down
around Baraboo and drove it to the scrap yard in Wisconsin Dells, where they
proceeded to smash it up. Gramps said one smack on each spoke and the
flywheel just shattered, he didn't think the castings were real high
quality! I think he could get a lot of argument on that one if he were alive
today. That was the spring of 1942, priorities were a little different then.
Sorry for being so long winded, been away from the 'puter for a while, but
now that we have a little snow, it is time to kick back and relax.
G'night,
Joe Prindle