New, Used, Rebuilt ... which way to go???
Helping to decide is purpose of this page. So here are some Important Buying tips, one of the very few things that the new Range Rover ABS Bible, Getting Comfortable with WABCO ABS brakes, Range Rover 1990 to 2002, third edition, does NOT tell you. Prices and information cited are approximations, current in early May, 2010.
In order to decide whether to buy a
new, rebuilt or
refurbished, or even a used pump, two other parts should be considered
as well. A great deal of confusion surrounds these terms.
This is made worse by the fact that Classics
use a different configuration. Let's see if we can
set it all straight.
Pump: Brake pumps generally last a very-very long time. If one has failed the cause is very rarely old age: the causes are usually a bad accumulator, a sticky pump-control-relay [$65], or a clogged filter. See The Book for details, for tests, and for repairs.
A "new pump" is only supplied as an assembly, and it therefore includes two other key components: a new accumulator, and a new pressure switch. Physically speaking, the accumulator and switch are easily removed from the outside of the pump if necessary. The assembly is made only by WABCO: there is no aftermarket version for sale. Accumulators, purchased alone, run between $275 and $375. New switches alone are no longer available -- except when purchased as part of a new pump [assembly], and rebuilt switches, such as ours, run around $350.
Accumulator: This is a wear item. Never would a used accumulator ever be of any interest!! They only last about five years and cannot easily be bench-tested, so the condition of any used one is a gamble anyway, plain and simple. Worse still, used accumulators will contain contaminants -- including bodily fluids from the donor, as well as their own deteriorated rubber guts -- which, if installed, will be introduced into your brake system immediately, likely causing new damage and new issues. There is no method for cleaning used accumulators: best to think of them as similar to used condoms ... sorry. They have in them whatever the last brake system they were used upon had in them: yuk!
The Range Rover Brake Book explains the details of how the accumulator is built, tested by the user, how it affects the life expectancy of the pump, and how it fails. Regardless, WABCO has never sold license to manufacture this part to anyone else, so whomever you buy a new one from, it is the exact same part. If your old accumulator [$300] was good when the pump failed, a new pump [$1350] may not be a good value when compared with a rebuilt one [$400]: just re-use your old accumulator.
Pressure Switch: These control the pump's operation cycles. Often, when they fail, the mechanic deems the entire pump bad. Yes -- a new pump assembly will include a new switch. But the switch does not fail with any regularity. It can be an issue, randomly, from time to time: some last hundreds of thousands of miles while others puke at 80k miles. As with any mechanical condition, use hastens their demise, and the worse the accumulator, the more the use-cycles on the switch.
The switch also faces the exhaust manifold. Our experience in refurbishing these switches reveals that some fail from just plain overcooking. In the long run a heatshield for the assembly might be wise.
Used switches can be found for $200 to $400 but are rare: since they don't necessarily fail from age, so this is a good alternative, if you can find one. A new pressure switch has never been available from Land Rover. Rebuilt ones are usually about $350.
RECAP: New pump assembly [$1350] comes with new switch [$400] and new accumulator [$300], so the new pump alone is worth about $650. Rebuilt pumps, without the switch and accumulator, but at 2/3 that cost [$400], work as well and will last as long as new ones. Used pump assemblies, if they come with switch and accumulator, still require throwing away the accumulator.
Pump faults are almost always caused by other things, things which the Range Rover ABS Brake Book explains in fine detail ... so that the owner can tell well in advance. Stay on top of accumulators, fluid, filters, and relays. Read the book and there's no reason to need to buy another pump!