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FREQUENTLY ASKED QUESTIONS
I can get new cylinders for my car. Why should
I have the old ones sleeved?
New, good quality (we mention that because there are many new cylinders being imported
that are of very poor quality) master cylinders are increasingly expensive. The
vehicle age
where the cost breaks even between new and sleeved&rebuilt moves forward in time
rapidly. Figure about $120 total for sleeving and a rebuild kit for a typical
single-circuit master cylinder. New, good master cylinders for some cars don't cost that much
yet, but many do.
Cylinders in cars that get fewer than a few thousand miles per year can be expected to
last perhaps 5-6 years before pitting is bad enough to chew up the rubber. If you are
planning to keep the car that long, you are ahead as soon as you don't have to do the
first brake job no matter how cheap the parts are. And sleeved cylinders are
a big selling point if you don't keep the vehicle.
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Why do you use brass? Why not stainless steel?
The proper grades of stainless steel are fine for sleeves
*if* they are installed properly. For metallurgical reasons, they must be put in with a
quite tight interference fit. This fit works fine on massive disc calipers, but can break
relatively thin-walled master and wheel cylinders. Much of the work we do is on cylinders
that are difficult if not impossible to replace, so we can't take a chance on breaking them.
We can use different assembly techniques with brass that do not risk breaking the casting.
We often re-sleeve cylinders that have had stainless
sleeves installed improperly. The typical failure mode for these cylinders is that the
bond between the sleeve and the casting fails, allowing the sleeve to push out of the
cylinder when pressure is applied. See a set of Dunlop
caliper pods with three out of four failed sleeves. The fourth sleeve was close to
failure.
It's important to note that these systems do not fail from
wear but rather from pitting caused by rust or corrosion. Brake parts move so slowly and
so seldom, relatively speaking, and are so well lubricated that wear just isn't a factor.
Even soft, non-anodized aluminum cylinders (that haven't been honed) show very little to
no wear if we can find enough uncorroded surface to get a measurement. If we can prevent
the pitting, we prevent the failure. The tempered brass we use is much harder than cast
aluminum and not much softer than cast iron. The additional hardness of SS is just not an
advantage in brake cylinders. In addition, brass is by nature a bearing material. SS is
not.
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Can you sleeve disk brake calipers?
We do those calipers for which sleeving is appropriate. There are two
basic designs of caliper. In one design the fluid seal is in a groove at the mouth of the
caliper bore, and it seals against the surface of the piston. In this design the critical
surface is on the piston, and the caliper bore need not be in perfect condition. In fact,
the caliper bore can be really ugly. As long as the basic diameter is intact, it will work
as well as a new one. There is no advantage to be gained from sleeving this type of
caliper, but the pistons must be in very good condition. Often the original pistons are
fine, and the calipers can be serviced with a simple cleaning and new rubber parts.
If you want this type of caliper rebuilt, we highly recommend
Goldline Brakes in
Seattle WA at 206-624-7740.
Certain makes and models of vehicles were noted for failure of the piston surfaces
due to peeling of the plating. Mid-sixties Mustang and Thunderbird
four-piston calipers were famous for this. The new pistons currently
available for these are much better than the original pistons.
In those relatively rare cases where good-quality new
pistons can't be obtained, we can sleeve pistons.
In the second caliper design the fluid seal is in a groove
at the base of the piston, and it seals against the bore. In this design the
critical surface is in the caliper, and the piston need not be perfect. Most
variations of this type of caliper can be sleeved. We refer the four-piston calipers
used on mid-to-late sixties GM, Mopar and AMC cars to
Goldline Brakes. We can sleeve
most other variations of this caliper type, including all sizes of
Dunlop caliper pod.
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My cylinder is made of a steel tube soldered into a "tin-can" reservoir.
Can you sleeve it?
Yes. There are various styles of these
"tin-can" cylinders, used mostly on British cars. The sheet metal can
must be removed from the steel tube before sleeving so we can clean the
inside of the can properly and so we can re-drill the fluid ports. Then the
can must be re-soldered to the tube in the proper orientation. We charge $30
to remove, replace, and pressure-test the can. Note that on rare occasion
the tin can may be badly rusted to the point that we are not able to get it
to hold pressure. We try to identify these before we start the job. Also
note that rusty cans will continue to deteriorate. We cannot be responsible
for leaks that occur in the wall of the can after the cylinder is put back
into service.
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What other cylinders involve extra work and additional charges?
We do occasionally encounter cylinders which require extra work and for
which we must make additional charges. We've put up a
page to show
these. Such cylinders are rare, so this page will grow quite slowly.
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How do I "flush and refill" my
system?
Remove as much fluid as possible from the reservoir. A
turkey baster (NOT the one from the kitchen drawer) works well for this. Refill with the
new fluid, then bleed according to the manufacturer's recommendation until the fresh fluid
shows up at each wheel, then a little more for good measure. If the manufacturer's
recommendation is not available, start with the cylinder furthest from the master and work
to the one closest. This will displace such a high percentage of the old fluid that the
remainder is insignificant. This routine is not sufficient for a change from glycol to
silicone, but is sufficient for any other change.
One important point--limit the travel of the brake pedal
if using the pedal to bleed (as opposed to pressure bleeding or vacuum bleeding.) If you
allow the piston in a used master cylinder to travel beyond the area of normal travel, the
layer of gunk on the cylinder wall can tear up the cups, causing failure of the master
shortly after. We put a block or blocks under the brake pedal to hold it about as far off
the floor as it is when the brake is applied. If you happen to be replacing or rebuilding
the master at the same time, so that you know the bore is clean all the way down, this
caveat does not apply.
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Can I paint my cylinders?
Yes. Glycol brake fluid is an extremely effective paint
remover, however, so regular paints cannot be used. Most two-part (catalyzed) paints are
resistant to brake fluid, but one-part paints such as spray paints are not. Some of the
conversion coatings sold to restorers are resistant to brake fluid. POR-15 is one such
coating. Note that some colors of these coatings may not be resistant, so ask your dealer. If
you're going to paint your cylinder, we ask that you let us do the sleeving
first. Be sure the painter masks or plugs all surfaces and ports that will be exposed to
brake fluid or covered by rubber boots or gaskets.
We use VHT Brake Caliper,
Drum, and Rotor paint with good results. Start with a clean casting,
mask gasket surfaces and plug ports, apply two thin coats per the instructions
on the can, allow to dry
overnight, then cure in an oven. The VHT website recommendation was originally
350 degrees for 1/2 hour and was later changed to 200 degrees for an hour,
but we find that's not quite hot enough to effect a full cure. We are
having very good luck curing at 250 degrees for one hour. There is minimal odor since most of the volatiles go away during the
air-dry, so you can do it in the kitchen without triggering a divorce. From our
experience, one can will do about four typical master cylinders. It makes a very
tough coating that is very resistant to brake fluid. Most original master cylinders were
bare metal, so the Cast Aluminum paint is probably most "correct"
although it is quite a bit brighter than cast iron. Our
personal preference is the Satin Black color. We try to keep all the colors in stock, and we will
paint and bake your cylinder for $25 if you prefer not to do it yourself.
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What about powder-coating or plating?
Properly cured powder-coat is quite resistant to brake fluid, as is any
kind of plating. Either makes a very nice finish for brake parts. We have
been told that epoxy powder is more resistant than polyurethane powder, so
you may want to ask your powder-coater if he offers your choice of color in
epoxy. We ask that powder-coating or plating be applied before sleeving. We take quite good care of plated or coated
cylinders.
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The boot rim on my wheel cylinder is broken. Can you fix it?
In most
cases, yes. Here's an example of a cylinder we
fixed. We have a stock of thick-wall tube in various sizes from which we
can quickly make replacement rims, which we then affix to the end of the
sleeve during the installation process.
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I can't get my cylinder(s) apart.
Can you help?
Probably. We have tools and techniques that give us a very high rate of
success in removing stuck pistons without damage to the piston or the
cylinder. Our most effective tool is a hydraulic pump that develops about 3500 psi, and a collection of adapter fittings. Of
course, we cannot guarantee success, but if we can't get it apart, it's
likely that no one can.
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Do you have replacement tube
seats?
Probably. We can get five different seats from the rebuilder's supply.
Three of them can be machined to make shorter versions. Here's a picture of
the five seats, with the shorter versions below.
The most critical dimension on these seats is the minor diameter--the
"peg" that press-fits into the casting. Major diameter of the body and
overall height are much less important. Working from the left:
| |
Minor Diameter |
Major Diameter |
Height |
Part # |
| #1 top |
0.192" |
5/16" |
0.35" |
5516 |
| #1 bottom |
0.192" |
5/16" |
0.3" |
|
| #2 top |
0.226" |
5/16" |
0.35" |
5517 |
| #2 bottom |
0.226" |
5/16" |
0.3" |
|
| #3 top |
0.251" |
3/8" |
3/8" |
9446 |
| #3 bottom |
0.251" |
3/8" |
1/4" |
|
| #4 |
0.192" |
3/8" |
3/8" |
21047 |
| #5 |
0.383" |
7/16" |
0.45" |
5518 |
#1 and #2 are usually used in ports
threaded 3/8"-24 which receive a 3/16" brake line , but may be found in
larger ports.
#3 and #4 are usually
used in ports
threaded 7/16"-24
which receive a 1/4" brake line, but may be found in larger ports.
#5 is usually used in master cylinder ports which may receive either
size brake line. GM, Ford, and AMC cylinders usually have ports threaded
1/2"-20 and 9/16"-18, but may have one or both ports of smaller size. MOPAR
cylinders usually have ports threaded 1/2"-20 and 9/16"-20, but again may
have one or both ports of smaller size.
The shorter versions of #2 and #3 are most commonly found in GM
cylinders and calipers. #4 is most commonly found in Wagner Lockheed
cylinders.
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Any special instructions for Canadian
customers?
We use the United States Postal Service for return shipping
to Canada because of UPS' ridiculous requirements for both sender and
receiver of Canadian shipments. Postage to Canada typically costs us about
$10 more than the average cost of shipping the same package within the US,
so we must add $10 per shipment to Canadian customers.
We require payment by credit
card, because our bank charges $15 to process checks and money orders
written on Canadian banks even if they are in USDollars.
How should I pack and ship my cylinders?
Cylinders should be packaged so that they cannot bounce around in the
box, or they may punch through the wall of the carton. Use enough foam,
crumpled newspaper, bubble-wrap, or other packing material to fill the box.
Be sure that brake fluid is drained from any cylinders that are still
assembled. If cylinders are wet, double-wrap them in plastic bags so they do
not leak into the packaging. Shipping people get very nervous when packages
start dripping smelly fluids.
You can ship cylinders using any service that is convenient for you. UPS,
FEDEX, and USPS are the most common. UPS and FEDEX provide tracking for all
packages. Tracking is available from USPS at extra charge, and is
recommended. We suggest paying the extra charge for Priority Mail if
shipping by USPS, as Parcel Post tends to be very slow. (We once received a
Parcel Post package that took 26 days to arrive from Florida, and two-week
transit times are common.) Most of the smaller services such as DHL and
California Overnight either deliver to Quincy or hand packages off to one of
their competitors that does.
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