Rear Brake/ABS Pump issue

[jamiemac]

No doubt you've read this thread from the start - a couple more for your info.

http://www.zggtr.org/index.php?topic=21794.0

http://www.zggtr.org/index.php?topic=21700.0;topicseen

Thanks for posting those! I covered a lot of threads over the past couple of days, and I'll read these too, even if I already did. LOL

I think I read this thread a few times, but I'll go through it again also. Repetition is good for my old brain.

[jamiemac]

I partially tore down my ABS unit, and found the sticking solenoid valve. Took the snap ring out, and freed it up. Cleaned it. Wasn't terribly dirty inside. Air will now blow through the rear brake line ports. I'll reassemble tomorrow, and test it out.

[Freddy]

That's great Jamie.  Which of the 2 is the rear?  After removing the ring did the cap slip out easily? 

No-one's ever reported front brake failure.  I wonder why?

[jamiemac]

That's great Jamie.  Which of the 2 is the rear?  After removing the ring did the cap slip out easily? 

No-one's ever reported front brake failure.  I wonder why?

I'm a little unsure what You mean here, "After removing the ring did the cap slip out easily?"

The top port, where my index finger is, goes out to the caliper, as the port by my thumb, is fed by the master. I took the control unit off, and freed up the solenoids. I was able to run fresh fluid through it, and get it lubricated. It wasn't really terribly dirty inside. I do bleed a pint of fluid through my brakes every couple of years. Bike is still apart, because I'm slow, so hopefully, I'll finish up and test ride tomorrow. Bleeding the system isn't as difficult as folks make out. Attach a hose to each bleeder screw, and place it in a container of fresh fluid. Fill the master, crack open the bleeders, and pump the pedal/lever. Take it slow. Use plenty of fluid. The most difficult brakes I've ever bled, were some of the earliest automotive antilocks. This works on all I've ever done, except early Bosch units. Those take another, super simple method.

[VirginiaJim]

That's great Jamie.  Which of the 2 is the rear?  After removing the ring did the cap slip out easily? 

No-one's ever reported front brake failure.  I wonder why?

My guess would be that it's used way more than the rear.

[jamiemac]

Yep. That's probably the most logical answer. I got no solids, or excess crud out of the unit, when I flushed it.

[Freddy]

My guess would be that it's used way more than the rear.

According to the information given to me by a senior Kaw service tech who authorised the replacement of my faulty unit 2 and a bit years ago (free of charge for investigation of the failure), the solenoids and therefore valves are cycled each time the bike is started and ridden those first few metres.  If the system is 'fault free' the ABS warning light is extinguished.  As we know, the ABS light goes off even with this fault, though the FSM details (in one of the other thread) that it is designed to detect this fault and warn the rider.

Jamie, I'm assuming (perhaps wrongly) that the solenoids are under the caps near your thumb.  Is that so?

[jamiemac]

According to the information given to me by a senior Kaw service tech who authorised the replacement of my faulty unit 2 and a bit years ago (free of charge for investigation of the failure), the solenoids and therefore valves are cycled each time the bike is started and ridden those first few metres.  If the system is 'fault free' the ABS warning light is extinguished.  As we know, the ABS light goes off even with this fault, though the FSM details (in one of the other thread) that it is designed to detect this fault and warn the rider.

Jamie, I'm assuming (perhaps wrongly) that the solenoids are under the caps near your thumb.  Is that so?

The cap by my thumb, is where the piston, driven my the pump motor are installed by the manufacturer. It's very difficult to install the pump motor, without taking out those pistons, because they ride on a cam, driven by the motor. It turned out to be unnecessary to take off the motor. Wish I'd known that ahead of time. You can see the pistons in the top pic.

The solenoid that sticks, is accessible by removing the control module from the back of the ABS unit. I simply worked the stuck shaft loose with a soft mallet. Once it started moving, I was able to use my fingers to work it in and out while pouring fresh fluid through it. A little dirt came out but I've seen cars that were much worse, and still functioning. I'd say Nissin screwed the pooch designing this unit.

Here is the pump motor in the bottom pic. If anyone ever attempts this fix on their own, I recommend NOT removing this, since it doesn't gain access to the problem area, anyways. It's damn tough to reinstall this this between the two opposed pistons.

[jamiemac]

I forgot to add, that after a 50 mile shakedown cruise, my motor scoot is back in service, and performing normally. As you can see in the pic, I'm extremely happy about it.

[gPink]

You look ....ecstatic....   Good work on the pump. Would you be interested in breaking this off into a thread of it's own? The Boss could then archive the repair.

[O.C.]

Your persistence has paid off Jamie..well done 

Tell me that you are happier than your picture suggests     

[Freddy]

Well done Jamie and many thanks for documenting this - you're the first to disclose the guts of the unit.  Glad to read it's back to normal. 

Question - what was the condition of the piston for the fronts brakes?

[Conrad]

I forgot to add, that after a 50 mile shakedown cruise, my motor scoot is back in service, and performing normally. As you can see in the pic, I'm extremely happy about it.

That's your happy face eh?   

I wouldn't want to see your mad face!!!

[jamiemac]

You look ....ecstatic....   Good work on the pump. Would you be interested in breaking this off into a thread of it's own? The Boss could then archive the repair.

Sure. I wasn't very diligent about taking pics and documenting the repair, but I can describe it in pretty good detail, I think.

[jamiemac]

Your persistence has paid off Jamie..well done 

Tell me that you are happier than your picture suggests     

I'm pretty darned happy. I'm just a lousy model.

[jamiemac]

Well done Jamie and many thanks for documenting this - you're the first to disclose the guts of the unit.  Glad to read it's back to normal. 

Question - what was the condition of the piston for the fronts brakes?

The frt brake solenoids seemed fine. I could move them with my fingers. I still flushed fresh fluid through them also. It's messy to do, and wastes a lot of brake fluid, but I think it works. After I buttoned everything back up, I had the idea to submerge the unit in brake fluid, but To do that, the pump motor would definitely need to come off, and I advise against that.

[jamiemac]

That's your happy face eh?   

I wouldn't want to see your mad face!!!

Seriously, I'm so glad to have my 2 wheeled therapist back on the road, I'm all relaxed and chilled out now.

[jamiemac]

I'm filing a report with the NHTSA. Here's the link for anyone else that want's to do it.

https://www-odi.nhtsa.dot.gov/VehicleComplaint/?_ga=1.19187646.76431778.1493232004

[MAN OF BLUES]

Great job man, many kudos..

I have a donor non functioning unit sitting here presently that I had planned on disassembling for a post mortem just as you did, but have not cracked it open yet... hopefully I find the exact same issue with this one, which will go a long way to corroberate the failure,

I will take as many photos as possible also during the event, and share them here also.

I should have done this a month ago, but the weather has not co operated here in Ohio, till just recently...

Just out of curiosity, where there any stampings and part serial numbers you noticed on the assemblies, that we may use for future references, to identify the production date or code for documentation?

Thanks again,

[jamiemac]

Hey MOB! Sorry I'm so late getting back on here. Been a long day fixing people's old clunkers. That's cool that You have an orphaned unit to tear down! A complete disassembly, down to the inside snap rings and valve assemblies would go a long way towards a better understanding of this thing. I have one pic here, of a pretty prominent number stamping, plus a shot of the plastic control unit with some numbers. I'm pretty disorganized when I do this stuff.