Prolong the Life of Those
Vinyl Carb Fittings!
Hereís a how to article on how to make a
set of heat isolating gaskets to install between the head and the vinyl
compliance fitting that the carburetor fits into. These are quickly heat
damaged in serviced, I personally get tired of people complaining about
them. So Iíve solved it for you! Get them out of direct contact with the
hot cylinder head and youíll greatly prolong their service life! This is
also a great way to make heat isolating intake gaskets for your Russian
made carbs if you run an older bike. I recommend 1/8" total thickness to
protect the vinyl compliance fittings and a 3/16" thickness to protect a
carb from overheating. If you use 3/16" thickness to protect your
compliance fitting, you may have to get longer fasteners to attach the
fitting. Stock ones are fine for a 1/8" thickness.
These gaskets are easy to make. No
complicated shop tools needed.
These are made from rubberized asbestos
gasket sheeting made by the Garloc Company. Itís about $7 per square foot
where I buy mine at a local hydraulic service company. This is 1/16"
sheet. You can get it thicker, but it becomes much more difficult to cut
Step-1: Make a pattern:
Remove your carbs and compliance fittings.
Get a piece of brown paper like from a grocery bag. Lay the paper on the
hole for the intake on the head. Then rub it with the edge of a wrench or
something similar. Donít let the paper move around. You want to make a
rubbing to use as a pattern for the gasket. Once you have a neat rubbing,
cut it out with scissors and a #11 X-Acto blade. Small hole punches can be
used too. These are available cheap at harbor Freight. NOTE! On the
outside circumference of the pattern, cut it out leaving an extra 1/8" of
material around the outside edge. This will strengthen the gasket and the
extra material will not get in the way of anything.
Step-2: Trace pattern onto gasket sheeting:
Lay the pattern on the sheeting and trace
around it with a permanent marker. See photo. I like to trace mine
lengthways with the grain of the gasket sheet.
Step-3: Cut holes:
IMPORTANT! Cut the holes out BEFORE cutting
the individual gaskets out to prevent them from splitting. The material
has a plastic quality to it and will deform as you punch holes. Do the
holes first. I like to punch the small holes first and then I punch out
the large ones. If you donít have a large hole punch like I use, just use
your #11 X-Acto blade and make multiple light cuts around the circle until
you have cut the center free of the sheet. If you punch the holes, youíll
notice it deforms the material in the direction it was punched. Just
gently tap it back flat with a mallet.
Step-4: Cut out the individual gaskets:
Using a heavy pair of shears, cut away the
individual gaskets leaving about 1/8 to ľ" around where you will make the
final cutting. Remember this stuff can deform. Doing it this way and THEN
making a final cutting will prevent deforming the gasket material. Now
make your final scissors cut to complete the set of gaskets. I made four
each 1/16" thick. So I can bond a pair together to get the final 1/8"
thickness I need.
Step-5: Bond them together to get the final
You can see in the photo I use old
fashioned "Gasketcinch" adhesive. It dries to a tack quickly and works
well. But silicone RTV could be used too. Be sure not to use too much as
the RTV will squish out. Using the applicator, apply a light coat to the
surfaces to be bonded. I also applied a light coating to the back side of
the compliance fitting to stick it well to the gasket. None is need where
it seals to the head. The Garloc will form a good seal on it own.
Remember? Itís deforms easily. It will mate to the imperfections and form
a good seal.
Step-6: Re-Install on bike:
Reinstall the compliance fittings & gaskets
on the head. I use blue Loctite on all fasteners. See the final photo to
see how it looks. I recommend synchíing the carbs after any maintenance
like this. Have fun!