Inline Tube - Wheel Cyl. Rebuild
Inline Tube - Wheel Cylinder
One of the largest problems with classic car brakes is that your brake fluid is
to be changed every few years. Brake fluid collects moisture over time, this
moisture has water in it and over long periods of time it creates rust. This
means the inside of your components are slowly corroding causing your system to
loose effectiveness. This happens with anything that has fluid in it. This
includes brake lines, master cylinders, wheel cylinders, and calipers. If your
car has been restored in the last few years keep up on the maintenance and
change your fluid every 5 years. If your car has never been restored and you are
wondering how you can improve the brakes, the first step is changing the fluid.
By getting the old fluid out and replacing it with new fluid you eliminate all
the moisture which will dramatically increase the effectiveness of the fluid
increasing hydraulic pressure by as much as 20 percent. Next you can replace the
old metal brake lines which can rust from the outside from being exposed to the
elements and can also rust from the inside from trapped moisture. Before
rebuilding any component you should consider the cost and labor factor. If the
component has never been replaced and it is the correct date coded part for the
car it is priceless, if the component has already been replaced with an after
market piece, the time in rebuilding may not be worth the cost of a replacement.
An original is always worth rebuilding. Most components have only a few rubber
seals that need to be replaced and they will be a good as new. Rebuild kits are
a small fraction of the component cost but take some labor time to install. If
you are working on a driver, seals are quickly replaced in a few minutes, for a
show car a more complete rebuild may be desired. All calipers, wheel cylinders,
and masters have manufacture markings and date codes specific to that year make
and model. Inline Tube replacements have the same shape and function but do not have date
codes or manufacture markings. For a concourse restoration these marking add
value and detail to the final restoration. By following the steps below you can
rebuild you components just like an experienced mechanic. Inline Tube offers all
the pieces of the rebuild from the rubber seals to complete caliper ready to
bolt onto your classic.
These are the original Delco cylinders and
they feature the Delco logo, part number, date code, and wheel cylinder inside
diameter of 15/16". The size is important when ordering the seal kit. There are
many different size cylinders so if they are not marked you may need to measure
the inside diameter with a dial caliper before ordering. If the wheel cylinders
are not original they may not be worth spending the time to rebuild. A
replacement wheel cylinder cost around $20.00 , the rebuild kit is around $6.00
and your time is worth something.
Drain the Cylinder of as much fluid as possible. In
order to get the piston out of the cylinder, leave the bleeder in place and take
an air hose at low pressure (25lbs) and insert the end in the brake line hole.
When applying pressure make sure your hands are clear of the pistons that is
making its way out of the cylinder. When the piston reaches the end of the
cylinder wall you will hear a pop of air pressure and the piston will be out.
If the dust boot does not come out with the piston pull it out with pliers.
Remove all pieces paying attention to the order and direction the pieces are
facing, it is easy to forget and improperly install the new parts. In this
assembly we will be reusing the pistons, center spring, and cylinder body. The
rubber seals will be discarded.
Once the parts are cleaned it is
time to phosphate the cylinders. A solution from
Palmetto Enterprises is used. On a propane portable stove get a stainless pot
big enough for the parts. Follow the mixing instructions for the solution, heat
to 175 degrees and drop the clean parts into the solution and once they stop
bubbling remove the parts from the pot and spray down with WD-40. The WD-40
heats up and turns to a heavy oil that will soak in and protect the finish. Only
use a stainless pot, other materials react with the solution causing pot failure
Now that the cylinder is completely
taken apart, take a look at the cylinder wall, the wall may have small pits, as
long as pits do not run under the inner seals it is ok. The seal is what holds the fluid
in so this area must be clean. If there is major
rust or heavy pitting where the seals ride this may result in a leaking cylinder
even after it has been rebuilt. Light pits located in the center of the cylinder
have no affect on performance.
This piston will ride against the inner seal. Since brake fluid collects moisture the
cylinder usually has a few pits but nothing that will affect the rebuild. If
there is heavy pits the cylinder may be unusable and a new one will have to be
used. Another option is to have the cylinder sleeved, this can cost $60 to $80
for each cylinder. The cylinder will be bored to the next size and a stainless
sleeve will be pressed in.
The assembly will go back together
the same as it came apart. First with your finger as a back stop, slide the
spring into the hole, then insert the piston seal with the smooth side out and
the convex side against the spring, next the piston will go in with the smooth
side in and finally the end seal as pictured. Repeat for the other side. When
installing the rubber seal and the end seal it is helpful to spray WD-40 or
apply brake fluid on the parts to make installation smoother. If you decide to
paint the cylinder the brake fluid will eat the paint.
Repeat the same process on the other end of the cylinder.
Once the end seals are in place, use a hammer and a
block of wood and lightly tap the seal ring into place. The seal has a metal
band formed into the rubber that must seat to the cast body. Once the seal is
tapped into place install the bleeder screw, wheel cylinder pins, and you are
now ready to install the finished wheel cylinder into the backing plate. The
silver and gold zinc parts can be re-plated or Inline tube offers new hardware.
Inline Tube - Brake & Fuel Lines,
Rebuild Kits, Brake Hardware, Disc Brake Conversions,
15066 Technology Drive
Shelby Twp, MI 48315
586 532 1338
Palmetto Enterprises - Grey Phosphate Plating
2311 A Old Parker Road
Greenville, SC 29609
PH (864) 246 3836
Bobís Boosters - Sliver, Gold, Black Zinc Plating
East Point, MI
PH (586) 774 8883