FJ1200 ABS/ mastercylinder/ hose fault?

[Ann]

Hi All
  after looking over the  bike it appears the  following
front brake drags slightly on the front but will lock up when ABS system is active, yeh front brake is slightly spongy- no crud in  master cylinder and  return appears to be working.
Rear brake locks up with ignition off or on, and will only release when bleed nipple is opened.

IM wandering if there is any way to  test  ABS unit and  if there is a guide on how to bleed it without   specialist equipment?? There is no bleed nipples on the unit so i guess it requires some sort of a  jumper cable or plugging into diagnostics??

i plan to  strip down the front brakes again to  double check, but ill order another set of seals, incase for some reason there is some sort of issue with them.

Just baffled to how a bike with sticking brakes has  now become worse after removing the crud from the callipers.

If there is a guide about the  ABS module on these,  how to bleed , test, please could you point me in  the right dirrection

[red]

Hi All
  after looking over the  bike it appears the  following
front brake drags slightly on the front but will lock up when ABS system is active, yeh front brake is slightly spongy- no crud in  master cylinder and  return appears to be working.
Rear brake locks up with ignition off or on, and will only release when bleed nipple is opened.
IM wandering if there is any way to  test  ABS unit and  if there is a guide on how to bleed it without specialist equipment?? There is no bleed nipples on the unit so i guess it requires some sort of a  jumper cable or plugging into diagnostics??  i plan to  strip down the front brakes again to  double check, but ill order another set of seals, incase for some reason there is some sort of issue with them.  Just baffled to how a bike with sticking brakes has  now become worse after removing the crud from the callipers.
If there is a guide about the  ABS module on these,  how to bleed , test, please could you point me in  the right dirrection

Ann,

It sounds like a hydraulic hose is badly degraded or blocked.  If those hoses are 30-some year old rubber, I would want to replace them first.  Smart money lately goes to braided stainless steel reinforced hoses.  Most hydraulic shops can make them custom for you, or there are kit$ available.  They come in colors if you like, and greatly improve braking performance. 

Speedbleeders.com can make the bleeding process an easy, one-person job.  They have a nifty fluid-catch bag that you will like, too. 

You can also get bleeder banjo bolts (~US$20 each) for the handlebar master cylinders.  Get and install new hydraulic washers, any time you remove a banjo bolt; do not re-use the old washers.  Make sure that all hydraulic fluids are clean and fresh.  Do not use brake fluid from a big old bottle that has been sitting around for years.  Small new bottles are the right stuff.  The DOT specs you need are printed on the Master Cylinder tops.  IMHO, accept no substitutes

To my knowledge, the fail-safe mode with the ABS is a pass-through of braking pressure, so whether it works or not, it should not be causing your troubles.  HTH.

[Pat Conlon]

Can someone with a GFSM (Genuine Factory Service Manual) look to see if there is some info the help Ann?

Red is correct. The old oem hoses degrade on the inside causing all sorts of headaches, however, I personally would not invest $$$ buying new hoses for the FJ ABS only to have to need different hoses when I get fed up with the ABS shenanigans.
I am not a fan of the FJ's ABS.

[red]

Can someone with a GFSM (Genuine Factory Service Manual) look to see if there is some info the help Ann?
Red is correct. The old oem hoses degrade on the inside causing all sorts of headaches, however, I personally would not invest $$$ buying new hoses for the FJ ABS only to have to need different hoses when I get fed up with the ABS shenanigans. I am not a fan of the FJ's ABS.

Pat,

I have not heard of the ABS causing those strange symptoms.  Does it not pass through fluid freely, when the ABS is not engaged or failed?  If so, the ABS (even if failed) should not be any problem.

If, at some point, the ABS really does get ditched, I believe any longer new hoses could just be re-tailored to fit the "bare" bike, as needed, for not much money.
All IMHO, of course.

[Pat Conlon]

Can someone with a GFSM (Genuine Factory Service Manual) look to see if there is some info the help Ann?
Red is correct. The old oem hoses degrade on the inside causing all sorts of headaches, however, I personally would not invest $$$ buying new hoses for the FJ ABS only to have to need different hoses when I get fed up with the ABS shenanigans. I am not a fan of the FJ's ABS.

If, at some point, the ABS really does get ditched, I believe any longer new hoses could just be re-tailored to fit the "bare" bike, as needed, for not much money.
All IMHO, of course.

With the exception of the 2 lower front hoses, all the other ABS hoses are unique and are not used on the conventional brakes....I count 6 ABS hoses not used...

[Ann]

Can someone with a GFSM (Genuine Factory Service Manual) look to see if there is some info the help Ann?
Red is correct. The old oem hoses degrade on the inside causing all sorts of headaches, however, I personally would not invest $$$ buying new hoses for the FJ ABS only to have to need different hoses when I get fed up with the ABS shenanigans. I am not a fan of the FJ's ABS.

Pat,

I have not heard of the ABS causing those strange symptoms.  Does it not pass through fluid freely, when the ABS is not engaged or failed?  If so, the ABS (even if failed) should not be any problem.

If, at some point, the ABS really does get ditched, I believe any longer new hoses could just be re-tailored to fit the "bare" bike, as needed, for not much money.
All IMHO, of course.

Ignition off-  front  brakes  drag slightly , even if you slam brake on or  pull the lever all the way to the bar. It it firm, but with force you can  pull the lever to the bar. Rear  locks up like a handbrake and does not release unless bleed nipple is opened to release presure and then instantly the  wheel is  very easy to turn by hand.
Ignition on and ABS  system ' working'  front brake  gets worse till it locks the front wheel like a handbrake. Rear brake is already a fail with ignition off, so  its a given it will lock up with ABS unit running.
But what is really wierd is ABS light stays flashing- so that would indicate to me it is not working, but doesnt  explain why   front brake appears to be affected negativily  by the engine running.


thanks to  replies  from everyone so far .

[aviationfred]

On the surface, your symptoms appear to me as faulty master cylinders. Personally, I would isolate components. In the attached photos. The Blue circled areas are banjo fittings. I would disconnect all of the circled fittings. Put a banjo bolt through the fitting, secure it with a nut and using a fine tipped air nozzle, blow compressed are through each line. Less than 20psi should do the job. I would also empty and completely clean out both master cylinders. Maybe even use a short blast of compressed air through the master cylinder fitting. This should clear out any foreign material in the lines and masters. Reconnect everything, fill with fresh brake fluid, bleed the system and see what the results are.
If.... after all of that, the calipers refuse to release after engaged, I would remove the ABS pump and throw it in a dumpster and convert the bike to a conventional brake system.


Fred

PS. There have been a few of us that have converted an ABS bike to a standard brake system.

[red]

On the surface, your symptoms appear to me as faulty master cylinders. Personally, I would isolate components. In the attached photos. The Blue circled areas are banjo fittings. I would disconnect all of the circled fittings. Put a banjo bolt through the fitting, secure it with a nut and using a fine tipped air nozzle, blow compressed are through each line. Less than 20psi should do the job.
Fred
PS. There have been a few of us that have converted an ABS bike to a standard brake system.

Fred,

Normally, I would not take any issue with your advice.  You do very well, IMHO.  This time, however, I must disagree.  There is no "maintenance" for 30 year old rubber brake hoses that I would accept, other than the complete replacement of rubber brake lines that were toast long ago, anyway.
Steel-braided hoses are the cat's meow, sure, but any properly spec'd new brake hoses would be far better than the old rubber hoses.  Most reasonably competent hydraulics shops can duplicate the hoses you have, if OEM is not available, and at for a fair price for custom work.

Check www.anywho.com for Hydraulic Hoses.  Give a local ZIP code, and the website will Sort the Search results by distance from you.  
I use Anywho for finding all of my local commerce - fasteners, fabric, fish, et c.

[Pat Conlon]

Yep, gotta agree with Red....

[Firehawk068]

In Fred's defense, I'm pretty sure the advice he is giving is simply to get to the root cause of the "Rear brake locking up" problem, and not as a permanent fix to ride the bike going forward............

I would also agree with Fred, in that the issue is most likely with the rear Master-Cylinder itself.
I have dealt with numerous issues with bikes that have sat for long periods of time, and unfortunately the rear master-cylinder is going to have to come apart. It needs a serious internal bore cleaning, and a reassembly with new seals.
The piston is most likely stuck in the bore.
I have not ever seen an issue with the ABS system causing this locking and holding pressure issue. Same goes for the brake hoses............I have seen internally degraded hoses, but never to the point where it will lock pressure in the caliper.
That is not to say that it couldn't ever happen...........just that I have never seen it.

As for the front brakes, some slight "dragging" is normal. on every single one of my bikes (past and current) if you push it around the garage you can hear the front brake pads dragging on the rotors slightly.
I'm not sure if this is what you are describing when you say the front brakes are dragging? Even if it is, given the age of everything in the whole system I would plan on rebuiding or replacing the front master-cylinder as well.
It sounds like the whole hydraulic system, (hoses and all) will need a thorough going-thru.
Like was already mentioned, hoses will need to be replaced and braided stainless-steel lines are just simply better in every way!

I won't try to steer you toward completely bypassing the ABS system and converting it to a conventional setup, but keep in mind that parts for that really aged ABS system are nonexistent unless you find old-good-used parts to replace it with.

[aviationfred]

Red and Pat, I agree 100%..... the old hoses should go the way of the Dodo. Thank you Alan, you caught my exact point.
Troubleshooting the system to find where the problem is. It would be a shame to invest in new braided ABS hoses only to find that the ABS pump is locked in the position to not release pressure once applied.


Fred