Turning over ABS motor manually?

SonicTheHedgehog

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Evening all.
I've a 2008 GSA with malfunctioning ABS (solid "brake failure" message, no red or yellow triangle) and no access to diagnostic equipment right now.
Based on the above, and the fact that the speedo and ASC both seem happy, my rationale is that the wheel sensors are fine and (based on discussions seen elsewhere) it's likely that the ABS motor's contacts have... gapped... or something.

I've managed to get the bike to, occasionally, POST to a flashing "I've not calibrated yet" brake failure message, and on one occasion to a clear dash (and a solid brake failure message when I applied the fronts, but not the rear), by dint of... erm... surgically whacking the motor housing with a hammer. :D
So, I'm at least slightly hopeful that things can be solved without major surgery or major expense. But this is my first collision with the brake-related stuff so:

a) Do things as I've laid out above probably make sense, including the "stuck contacts" probable diagnosis.
b) If so, is there a way to turn the ABS motor over manually? Is it feasible to pull the control-module from the pump housing and jump in some power from there? I'm looking at this as I don't really want to pull the module, as though I've dealt with car brakes in the past, I've never touched these, and I've seen conflicting information as to whether things can be bled manually without a GS911.
c) If the motor is likely to be unable to be spun back to life by my approximate efforts, where's the current favoured workshop for getting replacement reconditioned modules? Or is it "cheapest warranteed one offof eBay" territory?

Many thanks - all input and requests for clarification appreciated.
 
Sounds like the the brushes are stuck.. if so simply supplying it with power is a waste of time.

Remove brushes, rectify, and refit, it's all on youtube.
 
Don't hit it with a hammer!
Remove the ABS motor from the ABS unit and either clean up the brushes or replace with a brush assembly from a Ford fiesta ABS unit. Takes about an hour and costs about £50.
 
Don't hit it with a hammer!

A gentle rap with a screwdriver is usually enough :D

or taking your bike off a berm over 2 foot also works, and why the old BMW off road school bikes never had the problem. .. :D
 
You need to contact Fluffy Bridges of this parish - he has just stripped his ABS motor from his bike and has stripped it down to replace brushes and bearings. I am sure he will be happy to pass on his findings and help you out.
 
You need to contact Fluffy Bridges of this parish - he has just stripped his ABS motor from his bike and has stripped it down to replace brushes and bearings. I am sure he will be happy to pass on his findings and help you out.

How fortunate and timely this post is. Thanks Mike!

Once I've had my tea I'll post a thingy and go through it although as Steptoe says it's all on YouTube but there are some things not mentioned there that I have discovered which may be helpful...


Fluff
 
ABS info '07 GSA mine from new.

Sonic,

As mentioned its a well known problem and depending on the time available and your ability, several fixes are available.

a) buy a new unit - you don't want to do that.

b) send it for repair - there are several people who will do this for about £350 on the 'net.

c) replace with a Fiesta motor - its the same.

d) get surgical - assuming you know what you're doing.

There's plenty of fixes on YouTube and some on here and the ADV forum.

The problem is the ABS motor brushes get stuck in their holders. The start up test procedure only checks the circuit continuity so if the brushes are not in contact with the commutator segments the test fails and the warning lights flash... This is the third time I've been inside my unit, the first two were sorted in the short term by a clean and air line blow out. There's a post from me about it inc. pics Sept/Oct '14, I think. Can't find it immediately.

This last one was a bit more involved and involved stripping the motor completely, removing the end bearing to access the brush housing and freeing off the brushes after a soak in WD overnight. They were solid. Once I'd got a bit of movement I used very fine grinding paste applied to the brush housing to wear down the brushes and produce a proper free sliding fit. Flush out well with carb/brake cleaner.

The pics tell the story.

The problem you will have is removing the bearing as it sits in a recess in the bearing carrier plate. An armature bearing puller won't get in there and the bearing is tight. You could grip the bearing in a vice and drift the armature shaft off the bearing with a soft punch but the armature is relatively heavy and you will end up moving the armature on the shaft with the shock. Don't do it. You are not going to reuse the bearing so carefully destroy it in situ with whatever you have to hand and replace when you're done.

The original bearing number is 6000D (10 x 26 x 8) made in Taiwan and probably quite suitable for the job . I bought an SKF 60002RS for about a fiver.

I'm not regularly on the forum so if you need more ring on 07805 498017 evenings.

Fluff.

Note: in the pic the armature is facing the wrong way. The short end goes in the motor housing, the long end with the off-set sticks out the front...
 

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You mention the fiesta motor is the same, this is not quite true. the eccentricity of the shaft is slightly different. I have no idea what real world difference this makes but I decided to just use the brushes from the fiesta motor. Whilst these look the same as the BMW brush assembly, despite several attempts to make my BMW brushes behave they never lasted more than a few months before require further fettling. The Fiesta brushes have been in and trouble free for a couple of years now (touch wood....). Maybe I just had a brush assembly from a bad batch?
 
Thanks for that - the stuff I've seen thus far hadn't mentioned the bearing.
I'm currently tending toward somewhere between c & d, most likely pulling the motor when I have an opportunity and see if I can free the brushes, and progress from there.

On a tangent, does anyone know if there are any identifying marks on/in the hydraulic block from ATE as opposed to BMW rebadging?
I'm wondering if it's possible to keep the ECU and swap the HCU with a comparable version that has the motor bolted to it, as opposed to the drifted tabs. I'm aware this may qualify as a Stupid Question, but given organisations' propensities for just buying in ABS solutions and only changing the brains, it bears asking, and I've not found anyone else dumb enough to contemplate it yet in a quick search.
(This sprang to mind because ATE themselves sell a HCU module as, apparently, a drop-in replacement for the ABS systems of several vehicle manufacturers, with a view to solving pressure sensor etc problems with the parts cannon rather than diagnosis.)
 
The motor is staked to the ABS valve case - lumps on the alloy block are peened over to hold the motor in place. Taking the motor off means cutting the stakes away then you have nothing to hold the motor when you rebuild it. The fix is to drill and tap M4 not more than 5 or 6mm deep and use some large head screws. BUT nobody says where you can safely drill into the pump casing. So take care with that one.

As a thought - Is it possible to drill a 12mm hole in the motor case above each brush? Then you could check the brushes for wear/sticking. Cover the holes with blank grommets.

I put that as a question because I have no idea how deep the permanent magnets go and you don't want to hit them with a drill.
 
GSA ABS

I made a retaining collar for each side to relocate the motor and held it in place by just drilling and tapping the original pillars. Hadn't thought of just using shouldered bolts.
 

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I just epoxied the motor back onto the ABS body. Not as pretty as a bespoke retaining ring but it seems to be holding up and its less scary than drilling holes!

If you are nimble you can remove the motor from the ABS unit without removing the ABS unit from the bike.
 
Fluffy's idea is good and not too hard to file from some aluminium plate. The bolt holes are well away from any internal workings. Two smaller clamps would also do the job - flat end at the motor & pointy end looking neat at the edge of the ABS block.
 
You mention the fiesta motor is the same, this is not quite true. the eccentricity of the shaft is slightly different.

Looking highly likely I'll be replacing mine soon with a fiesta motor. What do you mean by the eccentricity of the shaft is slightly different? Does that mean it needs to be modified before install or is a direct swap?
 
Is it a case that once you get it in it’ll work fine? Also, how do you remove the old motor from the pump without removing the pump? Are there not tangs that need undoing?
 
If you run the motor and look at the shaft you will notice they dont spin true. They have and inbuilt eccentricity which is what allows them to build up brake pressure. I measured this on both the BMW unit and the fiesta unit and found the fiesta to be slightly more. I have no idea if this will make any difference at all in use but I decided to stick with the BMWs motor and just use the brushes from the fiesta.
There are lots of on line articles on how to pull the motor apart, its no more work than you need to do if you just clean up the brush holder assembly. I seem to remember you have to carefully drill out two spots in the motor body to allow you to be able to push back the plastic tabs that hold it all together.
 
I just want a working motor.

Too much ‘I can do this ‘ wankogy on the internet. It either fits or it does not!!!!!!!!
 
If you just want a working motor with no hassle then go to your main dealer and buy a complete unit.
If you want to save some money and are prepared to a bit of work yourself, fit one from a fiesta. You will need to find a way to secure it to the ABS unit.
I decided to just use the brush assembly from the fiesta unit, a little more effort maybe, is it worth it? I don't know... I decided the uncertainties of the fiesta motor made it worth it for me, you can make your own decision.
 


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