Rear brakes

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Ratman

Well-known member
Joined
Oct 6, 2005
Messages
74
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Location
Minnetonka, MN
Thought my brakes pivot point was locking up again, removed the shaft looked very clean and free from binding.Replace the components and still no brake travel, removed every thing again and started to find where the bind was? Couldn't find any thing wrong? Removed rear caliper shoved the pads apart still nothing? removed the brake line and pressed the peddle down nothing? Removed the line coming from the rear brake cylinder to the aluminum box what must be the ABS, nothing, I now have travel and the piston seems to develop pressure, but just by putting my finger over the hole where the brake line resides,I no much of a test?

So here's my question? Whats inside the aluminum box with all the lines coming in and out of it? Is there a drawing I can resource some info from it?

It seams like a simple system, and yet here I set with no brakes?

Bike is a 2004. ABS

Thanks for the sure to be coming help!!

Glen.

 
Based on your wonderful description I'm not quite sure what the hell your talking about! :blink:

But the aluminum box is the ABS pump and there is no diagram for it that I am aware of as it doesn't come apart.

Since I really don't know what your problem is I can't give you any advice.

 
Based on your wonderful description I'm not quite sure what the hell your talking about! :blink:

But the aluminum box is the ABS pump and there is no diagram for it that I am aware of as it doesn't come apart.

Since I really don't know what your problem is I can't give you any advice.
+1

A better question will get a better answer.

In my 07 FSM there is a diagram of the ABS pump. It has valves in it that stick.

 
A better question will get a better answer.

In my 07 FSM there is a diagram of the ABS pump. It has valves in it that stick.
+1

The ABS metering block has a pump motor that pressurizes some of the passages in the block. There are two part to the block, the front and rear ABS metering systems. There are solenoids, spool valves and pressure accumulators which are managed by a dedicated ABS computer. The metering block seems to freeze up in some rare cases, though as the FJRs ages it seems to be happening more often. The ABS metering block is slightly more secure than Fort Knox and can not be taken apart in a non-destructive way.

The Factory Service Manual has a block diagram and good description of the contents in the metering block. It isn't that hard to test the ABS system.

 
Read the test procedure, sure wish I would have read it two years ago.

I think I have some real problems and I am going to need a another ABS block. going through life fat dumb and happy has it's set backs?

Thanks

 
Read the test procedure, sure wish I would have read it two years ago.

I think I have some real problems and I am going to need a another ABS block. going through life fat dumb and happy has it's set backs?

Thanks
...and can be expensive!

 
I heard a story of one FJR that locked the rear brake while riding. Your's was not rear brake and mine was no ABS for the rear. I wonder if this is the begining of someone gathering data on affected bikes and reporting to NHTSA?

 
If you have no brakes at all I doubt it's the ABS system. I suppose it's possible, but it would be highly unlikely. I've never heard of problems with the ABS system causing a loss of all braking whatsoever.

How old is your fluid? Has that been serviced recently? If the brake fluid is good, I would be looking at the brake master cylinder next.

Have you tested your front ABS? Is it working?

Replacement abs pumps are very expensive. If it is the pump causing the problem, you could always just get non-abs brake lines and bypass it.

 
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From his description of disassembling brake lines and checking pressure at the rear master cylinder, I suspect his brake fluid is new. This would have also afforded a lot of opportunity to introduce air into the system, and the lack of pressure could be related to that.

 
I'm inclined to agree with Scooter above, I do not see this issue as being an ABS problem. If any of the parts in the ABS assembly stuck or quit working, I believe that you would still have normal brakes, just no ABS.

Glen, to get to the bottom of this issue, we will need you to explain a bit more about the testing that you have done so far. You said:

Thought my brakes pivot point was locking up again, removed the shaft looked very clean and free from binding.Replace the components and still no brake travel, removed every thing again and started to find where the bind was? Couldn't find any thing wrong?
When you say "no brake travel" do you mean that the rear brake lever wouldn't move (stiff) or thhat when you pressed the rear lever the caliper pistons and brake pads won't move and clamp the rotor?

Removed rear caliper shoved the pads apart still nothing?
So, you were able to push the pads apart, which means that fluid is able to be pushed back up into the reservoir. Right? If there was a hydraulic lock that prevented fluid from flowing it would happen in both directions.

removed the brake line and pressed the peddle down nothing?
Nothing as in no pedal travel or no fluid came out of the open hose?

Removed the line coming from the rear brake cylinder to the aluminum box what must be the ABS, nothing, I now have travel and the piston seems to develop pressure, but just by putting my finger over the hole where the brake line resides
Is that the master cylinder (at the brake pedal) or the slave cylinder (at the caliper)? And what do you mean by nothing? No lever travel? No fluid gushing out the end? No braking on the rotor? What?

We should be able to come up with some better suggestions with more details. That ABS assembly is very expensive and not very likely the problem.

 
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Hope I didn't lose my help?

Medical issues, going back in the 31st for another go to remove some cancer.

I would like to bring you up to date as what I have done. The fluid is new, I have removed the rear brake line and couldn't get any fluid flow when pressing the brake lever.

Replaced the rear master cylinder, left the rear hose off, filled the res and pumped for two to three minutes,nothing?

Pushed it back into the garage, don't work tomorrow so I hope somebody smart sees this an give me some advice.

I am ready to take it in so I can ride when I get out of the hospital.

Thanks Glen.

 
Glen ~ Been down that Cancer road myself a few times, and am keeping good thoughts for you! I wish you had a bit more of an opportunity to get some trouble shooting input from the folks here before you had to spend time in hospital!

Lots of really sharp mechanics and trouble shooters here (I am NOT one of them unfortunately), and they will bust their chops to help a guy out.

Good luck with the procedure. If you want to yak about the medical side a bit, my profile contains my e-mail address. I've been battling C since the late 60s, 1968 if memory serves, and so far am still "winning the battle".

Looking at the bright side: Every day is a bonus day, my friend! :yahoo:

Don

 
Hope I didn't lose my help?

Medical issues, going back in the 31st for another go to remove some cancer.

I would like to bring you up to date as what I have done. The fluid is new, I have removed the rear brake line and couldn't get any fluid flow when pressing the brake lever.

Replaced the rear master cylinder, left the rear hose off, filled the res and pumped for two to three minutes,nothing?

Pushed it back into the garage, don't work tomorrow so I hope somebody smart sees this an give me some advice.

I am ready to take it in so I can ride when I get out of the hospital.

Thanks Glen.
Glen,

Sorry to hear of your illness. Good thought headed your way in your continued battle.

From the last post, it sounds like you may have an obstruction in the low pressure hose running from the rear brake reservoir down to the rear master cylinder?

When you fill the reservoir with fluid and pump the brake lever it should (eventually) begin to push fluid out the slave cylinder hose end. But the problem is that you need to "prime" the pump so to speak and get the fluid into the master. If the MC is full of air it won't have much suction to draw the new fluid in (even though it is lower).

If you can get someone local's help with a MityVac to draw a vacuum from the slave end, you should be able to just suck the fluid down from the reservoir, and keep it always full so you don't introduce any (more) air.

 
Sounds good, would like to get my ride going so I will do what it takes. Been riding around on my other bike and it's just not the same.

The cancer is very localized and I have very good doc,s at the U of Minnesota.

As with all the great people on this link, Thanks!

 
So i found a Mityvac connected it up to the rear brake bleeder, made sure I had topped off the reservoir, opened the bleeder pulled a vacuum and nothing. pumped the brake leaver several times like 100, started up the bike for know reason no change.

Gents why cant I get fluid the the rear break?

 
So i found a Mityvac connected it up to the rear brake bleeder, made sure I had topped off the reservoir, opened the bleeder pulled a vacuum and nothing. pumped the brake leaver several times like 100, started up the bike for know reason no change.

Gents why cant I get fluid the the rear break?
Well, something is clearly blocking the fluid somewhere between the reservoir and the slave cylinder.

Try tracing the rear brake line backwards from the slave cylinder, up to the ABS Hydraulic block, and disconnect the line there. See if you can get any fluid out of the Hydraulic unit when you press the rear brake pedal. If no, find the line that comes from the rear brake master cylinder into the hydraulic unit and pull that off. If you get fluid out of that line (but not the previous step) it would indicate something is clogged inside the hydraulic unit.

 
This sounds like the diagnosis of heart bypass surgery.

Sounds like there may be an ABS metering block bypass coming soon.

 
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