ABS Pump - Range Rover Classic
Pump:Wabco 111, 3391, A0074, 418-501-010-0, NTC-6889
Ah, the ABS motor and pump. Lovely little design, parts for which are kept under lock and key by the British M5 Service with people like 007 making sure no rebuild parts ever fall into the hands of the evil Dr. No, or his henchman (people like us.)
What follows is my attempt at making my pump last longer. It was making a very loud whiney noise. I obtained a failed pump, used, and used some parts from it to make my own pump work properly. I tried to source bearings and other motor bits, but to no avail.
If you have found a source of parts for these little sons of bitches, please forward that info on to me, many, many people would be made very happy if you did.
Oh, and it did work so far... I've had the pump apart five or six times now to finally get the bearing cleaned up enough to freely spin. When it is super cold out side (<15F), the pump will again start to whine, but when the ambient temperature warms, the noise goes away. I plan on moving from Wisconsin to Miami to avoid the noisy pump problem.... it would be cheaper for me to move my family to Florida, then replace that damn pump.
ABS pump, pressure switch, and motor located on driver's side (NAS) inner
The infamous ABS motor, with its pants off! It don't look so damn scary now, does it? Well, it's not, unless you are trying to find parts to rebuild it! This particular motor was fried by a faulty ABS relay that stuck on and burned out the armature, brushes and the brush holders (plastic):
The actual hydraulic pump portion of the device. The silver piece is where the motor fits in so as to turn the pump. You can see the impeller pump bearing on the outer diameter.
Here I took off the silver motor coupling, the pressure switch is upper right with the electrical connector:
The electric motor on the left fits into the abs pump on the right, but first the silver coupling must be set in the black pump body:
Here are two ABS pump impellers, only one per pump. This is the part that actually builds brake fluid pressure, ultimately charging the accumulator with high pressure brake fluid:
The impellers have little metal cylinders which fit in the side of the black donut, when the motor spins them inside the pump body, the metal cylinders are forced outward by centrifugal force. They are retained by the bearing in the pump body.
This bearing retains the metal cylinders as they are spun by the motor, it's hard to see here, but the center shaft on which the black pump cylinder rides, is actually OFF CENTER to the bearing. This allows a varying volume to be created by the spinning metal cylinders because they are constantly extending out of and retracting into the black pump cylinder. Look above at the pics with the black pump cylinder in the pump body and you'll notice the gap is NOT constant between the bearing and the black ring, this is where the brake fluid is pressurized as the motor spins.
Here a side view of the metal cylinders that create the pumping action.
Bleeding the pump after install is easy, just open the bleed screw and let gravity force out the air, make sure your master cylinder is topped off, and clean brake fluid will soon emerge from the pump body all over your nice inner fender well. Manual says "use clean absorbent towels..." I say "...what a crock of baloney!"
If you think THIS is bad, wait till you bleed the accumulator! You'll have a nice pool of brake fluid down below the master cylinder that is hard to completely remove. If your truck is like mine, there'll be a nice crease of rust where previous brake work has left paint-eating brake fluid sitting there for years because the mechanic didn't take enough time to thoroughly clean the fluid up... thanks!
My personal suggestion: "...use clean absorbent cloths..."
You can just see the bleed screw poking up from the "...clean absorbent cloth..."
Ron Beckett made a good comment on this last picture... just rinse the area well with water... you should be able to remove the brake fluid with enough water.
Assorted ABS Motor Notes, text, and opinions...
Rover's North Website Links:
"... the rubber isolators that affix the assembly to the inner fender. ... these isolators are sourced separately, or only with the pump purchase? " Separately. Part Number and Price dependant on VIN number. 4 required, prices in GBP, in the UK. TO JA 618020 NRC 9773 2.47ea FROM JA 618021 ESR 1579 6.22ea Why change / What's the difference? Your guess is as good as mine. Ha! Also used on the Disco 89 to 98 for mounting the Diesel Air Cleaner. You were right about them being metric - 6mm. Bet that's really helpful :-)) - - David, Derbyshire, UK. '95RR2 - 2.5DT