Range Rover Classic - Rackspace Hosting

TECH LINE
[Rovers North staff receive phone calls daily asking for technical
advice, parts and accessory recommendations, off roading questions,
maintenance tips and repair diagnoses. Between calls, we
asked the Rovers North staff to share some recent technical questions
with us –ed.]
Steve Haskell (’93 Range Rover Classic)
Maintenance of the braking systems on Range Rovers, Defenders and
Discoverys often involves installing new disc pads and turning rotors.
All too often, you put it all back together only to find that you’re listening
to squealing every time you apply the brakes. How can you
avoid this problem
As a Porche and Audi mechanic, I found myself frustrated by customers
who disliked the noise emanating from their newly installed
brakes. So I contacted Raybestos experts for advice.
First, recognize that when brake rotors are turned [to level off
their surfaces], they often become magnetic. Most enthusiasts and/or
mechanics will rinse the rotors off quickly with distilled water or
brake cleaner. The problem is that the surface never gets clean this
way because the magnetism keeps metal shavings from the machining
firmly attached to the surface.
Step 1 - their recommendation to me was to use dishwashing
liquid to create soapy water. Wash the rotors in the water and you’ll
feel the rotor filings in the mix. Clean them this way first, and then
spray a light coat of conventional brake cleaner.
Step 2 – Use synthetic caliper grease sold at parts stores [e.g,
Permatex or similar brands] rather than the normal grease, on the
back of the brake pads. Brakes surfaces reach 400 – 500 degrees F;
if you’re using antiseize compounds or conventional grease on the
back of the pads, they will likely melt and drip off.
Mike Koch (ex- MOD Series III 109”)
Electrical problems can bedevil enthusiasts, particularly when the
Previous Owner left no schematics in the car when it was sold.
Recently, a customer called about his newly-purchased 2000 Range
Rover. It had Hella lights installed on the brush bar. The Hellas were
wired to go on only when the high beams were engaged; however, the
lights would only stay on when the owner actually held his finger on
the switch. If he released the switch, the Hellas shut off.
Step 1 - The starting point must be to trace the wiring from the
brush bar though the grill.
Step 2 - Look to see if a relay was installed; ideally, that will be
the case.
Step 3 - Test the relay to see if it works correctly.
Step 4 - Test the switch for the Hella lights to determine if it is
working properly
My key point is that if you don’t take the time to trace the wiring,
or have it done for you, you will not be able to diagnose the problem
effectively. Replacing a part right off the bat is generally ineffective in
electrical problems.
A customer called with concerns that their gearbox had become
stiff and difficult to engage smoothly. What steps should they take
Step 1- It sounds so basic, but often this problem results from
low hypoid oil levels in the gearbox. Check the level by removing the
fill plug on the left side of the transmission case. More often than not,
it’s quite low. If you can find any to examine, you want to see a glossy
brown color. If you run the oil between your fingers, you should not
feel grit or metal filings. If your fluid is quite dark consider draining
it out and replacing it with new gear oil. If it’s milky, then it’s contaminated
with moisture.
Step 2 – Check the transfer case, too. That fill plug is on the back
side of the transfer case, behind the transmission. If it is low, then fill
it to level. Hint -if it gushes out at you and you have found the transmission
down in level, then you have a bad seal between the transmission
and the transfer case. Know that you will have to fill the transmission
and release some from the transfer case until you remove both
from the car and replace the seal.
Step 4 – Make certain that your clutch fluid level is up to the fill
line in the clutch reservoir. Look at the fluid color –if it’s gray or dark,
you might have disintegration of the rubber seals inside the clutch
master cylinder. Your fluid level will be normal but the clutch action
will feel ineffective rather than spongy. Fluid is likely leaking past ineffective
seals.
Step 5 - If the fluid color is light brown and you have a firm
pedal, then crawl underneath the right side of the car beneath the
slave cylinder. If you have a Series I, II or II-A, you want to make certain
that the adjustment nuts at the slave cylinder rod are at the correct
length. The distance between the top of the slave cylinder to the
adjustment nut [the top one of the two on the pushrod] will be 2 7/8
inches. Use a set of calipers or even an elementary school compass to
effect the measurement.
Step 5 – If the fluid level in your reservoir is down, and you don’t
have a firm pedal, then you might have a leak at the slave cylinder.
Check for fluid leaks around the slave cylinder, or at the point where
the rubber clutch line screws into the slave cylinder. Slave cylinders
can be rebuilt, but you’ll need to make certain that the inner surfaces
are very smooth and clean. If you have much pitting inside the cylinder,
a rebuild kit probably won’t work.
A customer replaced a Zenith carburetor with a Weber 34 ICH
on a ’72 Series II-A. Why will it run only when the choke cable is
pulled out
Step 1 - Make certain that you have adjusted the mixture screw
to the factory setting. Turn the mixture screw [the long screw at the
bulkhead side of the carburetor] in all the way, and then back it off 2
½ turns.
Step 2 – Make certain that the carb is tightly installed on the
intake manifold. Make certain that the top carb cover screws [there
are 4] are tight, also.
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