ABS Booster Pump - Repair or Replace? Part Sources? Rebuild in DFW, TX (3 Viewers)

[dinnertime]

I replace my motor today without removing the master cylinder, was pretty straight forward and was done in a little over an hour.

I disassembled the old motor and found the commutator bars extremely worn ( I didn't removed it from the housing since it has to be in good condition for my core charge to be refunded otherwise I would have measured it with a micrometer) and the brushes had tons of carbon build up. Not to mention the housing itself was full of carbon, I've got pics ill try and get uploaded tomorrow.

I bought my cruiser cheap with a known brake failure issue that "fixed" itself when I went to pick it up and trailer it home. I've had it for a month and the brakes have been fine. I have no doubt the motor was the issue once I got it apart.

 

[LimaBravo]

My ABS pump started making a loud grinding sound about two weeks ago before turning on the ABS and brake warning lights with the buzzer. Pulling the ABS MTR 2 fuse stopped the noise. Once it had cooled down, I bled the brakes and that fixed it for a little while until the pump completely stopped working. (ABS and brake warning lights, buzzer, and lost boosted brake pressure shortly thereafter). Dealer wants $3,800.00 to replace the whole thing.

I'm going to ship it to Eurton in Whittier, CA, but when following the steps to remove it, found the ABS motor connectors very corroded. What size connectors are those if I want to replace them?

Also, does anyone have good pictures of the motor bolts thanks need to be pulled? They seem to be hex heads, but I want to be sure.

 

[2001LC]

The corroded screws and nuts are available from Toyota Dealer, also the wires. Interesting your pump went out and you find this. It was after I repaired a local mud members ABS (replaced ABS) finding these corroded, I started inspecting all rigs for this corrosion.

If you look in my signture at The 2007 Unicorn. You'll find and index in OP. Follow it to "ABS to booster pump wire inspection & repair. Starts at post#219 on page 11." and you'll see how I drilled out the screws and part numbers in post #221.

 

[musthave]

I replace my motor today without removing the master cylinder, was pretty straight forward and was done in a little over an hour.

I disassembled the old motor and found the commutator bars extremely worn ( I didn't removed it from the housing since it has to be in good condition for my core charge to be refunded otherwise I would have measured it with a micrometer) and the brushes had tons of carbon build up. Not to mention the housing itself was full of carbon, I've got pics ill try and get uploaded tomorrow.

I bought my cruiser cheap with a known brake failure issue that "fixed" itself when I went to pick it up and trailer it home. I've had it for a month and the brakes have been fine. I have no doubt the motor was the issue once I got it apart.

@dinnertime Besides the two bolts holding on the motor, anything else? I'm trying to remove without taking the whole master cylinder off.

 

[dinnertime]

@dinnertime Besides the two bolts holding on the motor, anything else? I'm trying to remove without taking the whole master cylinder off.

@musthave I have a 1999, so I removed the Evap canister to make it easier. I used a locking extension with a hex key socket to get the two hex head bolts out. Once broken loose you can remove them by hand. If you use a flashlight and look between the accumulator and master cylinder you can see the hex head for the rear bolt if you're looking straight down from the top.

You do have to wiggle the accumulator around a bit to get the rear booster motor mount out but then its easy. Once thats out you can move the motor to where you can get the power wires off and remove completely. I have some pictures I took, but realized they were not the best after the fact and decided against doing a write up.

 

[LimaBravo]

Thanks @2001LC . Your thread was super helpful.

@musthave , I would check your motor wires first. If you need to drill those out, you'll probably want to pull it out anyway.

You'll need a 5mm hex key to pull the two bolts. You want the two on the right side of the vehicle (left side if you're looking at it from the front). I needed to use aa large screwdriver to break the motor away from the accumulator. Also, there's a small circular gear interface that may fall out which you don't want to lose.

I spent an hour looking at it trying to figure out how to do it without removing the entire unit and then spent an hour just removing the whole unit. If you follow the instructions in the diy master cylinder rebuild, it's straight forward.

And for me, having to drill out the corroded electrical connection, I was glad I got the whole unit out at the same time.

 

[LimaBravo]

Also, releasing the two hex bolts that hold the accumulator in place will make it easier to remove the ABS motor. The motor bracket extends about ¾" into the motor and I didn't want to risk tearing the vibration damper.

Trying to remove the motor bracket is impossible with a normal hex key as the second bolt is too close to the motor, so you have to move the accumulator out of the way and wiggle the motor towards the passenger side of the vehicle.

They're the 5mm hex heads that go through the bright clean spots on either side of the accumulator. (I moved the accumulator down in the image).

 

[LimaBravo]

Here's the gear interface to account for if you pull it out without removing the master cylinder. Mine fell out very easily, but I removed the pump once I had the master cylinder outside the engine bay.

At 330,000 miles, not too bad looking.

 

[musthave]

Got it off today. Wires are so rusted on to the screws they've almost become one. Stripped all 4. Trying to figure out how to remove the stripped screws. Any ideas?

Meantime, does anyone know the part number for the blue/red wire combo?

 

[dinnertime]

@musthave 89639-30100

Got it off today. Wires are so rusted on to the screws they've almost become one. Stripped all 4. Trying to figure out how to remove the stripped screws. Any ideas?

Meantime, does anyone know the part number for the blue/red wire combo?

 

[LimaBravo]

Drill the rusted screws out very, very carefully. If you're perfectly on center, a 5/32" drill bit will fit without damaging the nut threads. And then break them off with a pin punch. They're each held by a small nut that's nested in the plastic. If you try to use a screw extractor, you'll snap the plastic...err...hypothetically that is.

 

[LimaBravo]

See the post by @2001LC above for some pictures of how to drill then out properly. It's on post 221 of his 2007 unicorn thread.

 

[2001LC]

I took my time and use drill bits progressively larger, so's not to damage electorid (brass hangers/connections coming from ABS and booster).

Dipping drill bits in cutting oil (any oil) an running drill at very slow RPM is also helpful.

Once head drilled. I then drilled out shaft of screw just enough it freed from electoriod that's held by plastic. On ABS I found I didn't need to bend electoriod, just pushed up and out (once drilled).

On pump, I bent electroid just enough to remove nuts.

Look at The Unicorn starting with post #219 for additional pictures and tips. Scored a 2007 Unicorn. The holy grail of 100 series.

 

[Bryanl]

It's been over a year since I replaced the pump/motor/rebuilt the master and less than 10k miles but all is still perfect. Just thought I would provide an update.

 

[musthave]

Drill the rusted screws out very, very carefully. If you're perfectly on center, a 5/32" drill bit will fit without damaging the nut threads. And then break them off with a pin punch. They're each held by a small nut that's nested in the plastic. If you try to use a screw extractor, you'll snap the plastic...err...hypothetically that is.

I tried the extractor first, broke the plastic. I'll try the 5/32" and get it out. Then find someway to secure / glue the plastic so

 

[musthave]

So, have everything back together. Bled the master cylinder after a rebuild. Bled the front then the rear. Turned on, bled the front, bled the rear. Repeated front and rear with power on and off 2 more times. ZERO air, all crystal clear fluid at all four corners.

When I turn on the ignition the pump motor comes on for a few seconds. When turned on and pushing on the brake pedal it also turns on, off, at different intervals. Feels like it is working just great.

BUT, the piercing alarm hasn't stopped. Does it need to be reset? What do I need to do to get that to stop?

 

[musthave]

So, if you experience an issue whereby the screeching piezo alarm doesn't stop, do this.

Turn vehicle off. Turn key to on, let the pump run for 5 seconds. Once the alarm starts turn vehicle off. Now pump the brake pedal 40 times.

Pop the hood, then turn vehicle on but don't start it. You'll hear the motor kick in, it will turn on for a few, then off for a few, and will repeat several times. You'll notice the brake fluid go down so make sure you have some and don't let it go below min line. Continue to wait until the motor no longer cycles. Now start the vehicle. The loud piezo buzzer should be off and so should the lights.

Worked great for me.

 

[2001LC]

Instruction to properly fill the reservoir is on top of it. Make sure you read them!

 

[lt1fire]

Fyi, you can remove the motor without removing anything else. My hands and arms are pretty large so theres no excuses. Be sure to have one of those handy mirror on a swivel/extension for the rear bolt or you can do it by feel.

Since its getting cooler now, my motor is squealing also. I removed it and inspected it. Seems like the bearings were almost seized up. The commutator has roughly 75% life left by looking at the shoulder. The brush still looks thick. I'll attempt to find/replace just the bearings in the next couple weeks and report back. Good thing my 80 isn't sold yet.

Tried to get mine off last night. Is it just the two bolts that bolt the motor to the accumulator that you need to take off? I got those off but couldn't wiggle the thing free. Am I missing something here? As I recently bled the brakes I don't want to pull the MC and have to do that again so i'm trying to get the thing off without taking everything else off.

 

[LRIwater]

Tried to get mine off last night. Is it just the two bolts that bolt the motor to the accumulator that you need to take off? I got those off but couldn't wiggle the thing free. Am I missing something here? As I recently bled the brakes I don't want to pull the MC and have to do that again so i'm trying to get the thing off without taking everything else off.

I was also able to get the motor off without removing anything else. You need to push the motor toward the fender as the motor shaft protrudes into the pump at the front (front being toward the engine). There is a rubber grommet that aligns the motor case at the back (near the fender) that can compress to give you enough room to wiggle it free. Hope that helps. FWIW, I pulled the original motor, replaced it with two other rebuilt motors, replaced the accumulator with a low mileage one, had the dealer bleed the brakes, and nothing worked. I had to buy the entire new master cylinder assembly including the accumulator, pump, and pump motor from the dealer.