This procedure runs through bleeding the brakes on your Elan. This
material contained on this page is informational in nature only,
and does not imply all knowledge needed to safely work on the braking
system of your Elan! I will not warranty the contents nor will Lotus
Elan Central take responsibility for your actions if you should
attempt to work on your Elan's brakes based solely on these instructions

When to Bleed your Brakes:
Because DOT 3 & DOT 4 fluid is glycol based, it absorbs moisture
over time. Moisture seeps in through microscopic pores in the rubbers
seals and hoses. It enters every time someone opens the master cylinder
reservoir to check the fluid level. Most fluid reservoirs are transparent
so the level can be checked without having to open the lid. Brake
fluid is so hygroscopic (attracts water) that leaving the lid off
fresh brake fluid can ruin it overnight--it will absorb so much
water from the air it will be too contaminated to use.
Moisture contaminates the fluid causing a drop in its boiling point
which leads to fluid boil and brake fade during hard use. Moisture
causes internal corrosion in the calipers, wheel cylinders, and
steel lines. The reason for replacing the fluid periodically is
to get rid of the contaminated fluid and to restore the heat and
corrosion resistance of the fluid.
When a car's brake fluid is one year old, it contains 2.5% water.
At 18 months, the water moves up to 3% which is enough to lower
the boiling point of the fluid by 25%. After a few years, fluid
can have 7% to 8% water. Many experts recommend changing brake fluid
at two years or 24,000 miles. At the very least flush the brake
fluid completely at every brake job.
You SHOULD bleed your system and change your fluid at least once
a year to get the moisture laden old fluid out. Your brake system
will last much longer this way as the moisture in old fluid causes
corrosion of the brake systems internal parts. If you are racing
or using the car for hard driving and braking, the fluid changes
should be much more frequent than that.
Fluid Fade:
Fluid fade usually has a gradual onset--the phenomena is started
by the boiling of the brake fluid in the calipers. This produces
bubbles in the brake system. Since bubbles are compressible, this
makes for a soft, spongy pedal. In worse cases, the pedal can plunge
to the floor with very little slowing! Fluid fade can be avoided
by running a high grade racing-type brake fluid and/or frequent
changes of brake fluid. Also if you change the pads before they
get super thin, the thicker pad friction material will help insulate
the calipers from the heat.
Bleed versus Flush:
There are really two different things to do with brake fluid: bleed
and flush. Bleed is where you replace a little of the fluid. This
may be done after a brake pad change or after boiling the fluid
in the calipers. Flushing the system is where you replace all the
fluid in the system. This would be done on a yearly or bi-yearly
basis or after major brake system work. Both bleeding and flushing
the system are often referred to as "bleeding" because
the valve on the caliper is called a "bleed valve." What
will be called "bleeding" in this write-up is technically
a "flushing"!!
Parts Needed:
Brake fluid (see discussion above)
Brake cleaner spray
Tools Needed:
Protective gloves
Jack and jack stands
Wheel lug wrench
Torque wrench (recommended and worth buying!)
Bleed Screw wrenches (9mm AND 10mm)
"turkey baster" (read on!)
clear vinyl hose, about 30 cm. (auto or hardware store)
catch bottle (empty, screw-top soda bottle)
(you can get a "bleed kit" with the tubing and catch bottle
at the auto store)
flashlight or work light
small rubber mallet
Before you start: Brake fluid is hydroscopic which means it has
an affinity to water and absorbs water from the air. When brake
fluid absorbs water it’s boiling point drops rapidly. That
why it is important to use only very fresh brake fluid, preferably
from a recently opened bottle where the factory seal has just been
broken. When bleeding brakes, keep the bottle capped except when
you are pouring the fluid out. It is also a good practice to keep
the cap of the master cylinder reservoir on, but only loosely screwed
about ½ turn while you are bleeding, as the brake fluid pulls
in the humidity from the air and thus you want to minimize its direct
exposure to the air. Only use brake fluid that hasn't been previously
opened.
Bleed one wheel's caliper at a time, doing them in order of decreasing
brake line length. This means:
rear right, rear left, front right, front left.
Bleed Procedure: (Stroke Method) This
method is traditionally a two-person job.
- Open the hood. Clean around the cap of the brake fluid reservoir,
but do not use water now (remember water is your enemy here!).
Remove the cap, then remove, by sucking out (you should buy a
$3 turkey baster) all the fluid in the reservoir until you can
see the intake opening at the bottom of the reservoir--use flashlight
if needed. Leave just enough fluid to cover the holes. Then slowly,
as not to mix the fluids more than necessary, fill the reservoir
with new fluid to the very top.
- Go to the first wheel caliper you plan to bleed. Take tools,
paper towels, brake cleaner spray, and the work light.
Loosen the wheel lug nuts just a bit!
- Jack this corner of the car up enough to remove the wheel. Be
careful not to scrape the front of the wheel as you set it aside.
- Ah-ha, there's that famous Lotus suspension again. Now is your
time to inspect the current condition of your suspension parts,
bushings, brake lines, calipers, rotors, brake pads, etc. Be sure
you do not need to replace the brake pads before this brake bleed!
(see front brake info)
- Remove the plastic dust cap from the bleed valve on the caliper
(do not lose it).
- Place the correct wrench over the valve--the rear screw is
10mm and the front screw is 9mm. Then push the vinyl hose over
the valve, capturing the wrench. Put the other end of the hose
into your catch bottle. You may want to make a circle/loop with
the tubing so air cannot rise within it!
- Gently tap the caliper with the rubber mallet to help the air
bubbles rise to the bleed nipple--repeat as needed.
- Get your accomplice (#2) into the driver's seat, with his/her
foot on the brake. #2's job is going to be pumping the pedal,
to force fresh fluid from the reservoir out to and out of the
caliper.
- Be sure to add the NEW brake fluid to fill the reservoir full
prior to beginning the bleed at each corner!!
- Have your friend apply pressure to the pedal. You (#1) crack
the valve on the caliper, about 1/4 to 1/2 turn, and let fluid
drain into the catch bottle. When #2's foot has pushed the pedal
partway down, s/he signal's #1, who then closes the valve lightly.
- Do NOT push the pedal to the floor--this can cause damage to
the seals of the master cylinder. You should only push the pedal
as far as the normal travel. You can place a piece of wood, your
other foot, or other hard item behind the brake pedal to assure
you do not depress it too far.
- Important!! #2 should NOT release the brake pedal until #1 has
closed the valve. Otherwise, the rising pedal will suck air back
into the caliper (BAD!!).
- The two of you need to establish a coordinated rhythm. Something
like:
You need to repeat this cycle a number of times. Look through the
vinyl hose, watching the quality of the fluid coming out the valve
- If you're flushing the fluid, the number of pumps needed depends
on the line length. Look for fresh, clean fluid coming down the
hose. If you're replacing standard brake fluid with ATE Super
Blue, it'll change colors--> a-ha, the reason to get it! From
golden (or brown), it'll turn green, and eventually blue. Keep
bleeding until it's a nice Smurf blue
- In all cases, watch your fluid level in the reservoir. Do NOT
let it fall more than half-way down! If the reservoir runs dry,
you will suck air into the lines and have to start all over. Watching
the reservoir and keeping it filled is a possible job for a third
person
- When you're done with a valve, close it snuggly, remove the
hose and wrench, and replace the dust cap. Wipe up any fluid which
has dripped and clean the area with the brake cleaner spray. Brake
fluid will remove paint if left alone, so be sure to clean properly!!
Replace the wheel and move the jack to the next corner
- And when you're done all 'round, check the pedal feel. If you
have any doubt about the work you've done, don't drive the car.
Get help!
- Top off the brake fluid reservoir to the "Max" mark,
replace the cap, and wipe up any spilled fluid
Bleeding using a Hand Vacuum Pump: (Vacuum
Method)
You may want to invest in a simple vacuum pump to bleed the brakes.
One such tool, (supposedly??) available for about $20 at Walmart
is the "Mityvac Vacuum Pump / Brake Bleeding Kit." The
pump is applied to a bleed nipple, and pulls fluid through the system.
This technique has the advantage that it is a one-person job! I
have not seen this product or heard from anyone that has actually
used it so can give no feedback about it.
Griot's Garage sells (among other neat things) a neat little vacuum
extractor for $65. This is what I use! It has a brake bleed valve
end-attachment. ITEM#10122, phone 800-345-5789.
Similar method here except you can do it by yourself and save all
that pizza and beer money and payback-favor-time needed for your
helpers!
In brief: connect hose to bleed valve, build small pressure in
line (one pump of handle), crack valve open, observe slow fluid
flow out, be patient, wait more, hang in there, observe the fluid
change colors, close the bleed valve, remove the hose, clean up,
and get on to the next caliper!!
Important: Do not build a high pressure using a vacuum method.
This can cause cavitations within the fluid and/or can cause air
to be drawn in thru the bleed screw threads!
HINT: I found it best to fully remove the bleed screw, put a single
turn of white thread-seal tape around the screw threads, and then
re-install. This assures an air-tight seal for use with the vacuum
method.
DIAGNOSING BLEEDING PROBLEMS:
No air or fluid will come out the opened bleeder screw
A. Bleeder screw plugged
B. Brake line, hose or valve damage
C. Air leaking in through bleed screw
D. Master cylinder outlet plugged
Low or spongy pedal after bleeding
A. Air in the system
B. Mechanically related
Speedbleeders:
I am working on finding the proper Speedbleeders for the Elan!
Check out their web site at http://www.speedbleeder.com/
These are pretty cool and are getting rave reviews from all the
magazines and auto web sites. They eliminate time consuming and
messy brake bleeding and make it a one-person job! Simply install,
loosen 1/2 turn, slowly step on the brakes about 4-5 times, tighten
and you're done! This valve bleeds the brakes without allowing air
back into the system using a spring check valve! Simple and Ingenious!
COST and TIME EFFECTIVE!
Cost should be about $6.50 each.
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