Changing Brake Fluid

[Keith]

I will be doing the 16,000 mile service on my 05 ABS shortly. The Service Manual has a pretty straightforward procedure for bleeding the brakes (I will use a Mity Vac), and part of the procedure is testing the ABS hydraulic unit with the special ABS Test Connector.

My Question - since I don't have a test connector, can anyone who has changed their brake fluid on an ABS model tell me if there is any downside, such as an ABS fault, if you change the brake fluid and don't test the hydraulic unit?

Thanks,

Keith

Stillwater, NJ

 

[Newfie Bullet]

I will be doing the 16,000 mile service on my 05 ABS shortly. The Service Manual has a pretty straightforward procedure for bleeding the brakes (I will use a Mity Vac), and part of the procedure is testing the ABS hydraulic unit with the special ABS Test Connector.
My Question - since I don't have a test connector, can anyone who has changed their brake fluid on an ABS model tell me if there is any downside, such as an ABS fault, if you change the brake fluid and don't test the hydraulic unit?

Thanks,

Keith

Stillwater, NJ

Change the fluid on my ABS 04. I didn't touch the ABS Unit and didn't experience any problems.

 

[JimLor]

Same here on my 05 ABS. I used a MityVac and didn't touch the ABS unit - haven't had any problems in ~3k.

 

[dgfella]

Changed fluid on my '05 ABS this past weekend with no fault codes or problems. I tested the hydraulic unit by stomping on the brakes

 

[Coyote]

My Question - since I don't have a test connector, can anyone who has changed their brake fluid on an ABS model tell me if there is any downside, such as an ABS fault, if you change the brake fluid and don't test the hydraulic unit?

Does something need testing after bleeding?

Also too. I don't own any brake bleeding gadget (yet), but I want to do the reverse bleed, where the fluid is pushed up through the system. Is there any reason not to use this technique on an ABS system?

 

[Keith]

According to the service manaual, you should test the ABS hydraulic unit as part of the bleeding procedure. Based on the responses to this thread, I would say that it is not necessary.

 

[ionbeam]

since I don't have a test connector, can anyone who has changed their brake fluid on an ABS model tell me if there is any downside, such as an ABS fault, if you change the brake fluid and don't test the hydraulic unit?

The ABS unit has fluid control valves and a pump. When you do a straight brake bleed it bypasses these items. When you 'test' the ABS system you cycle the fluid control valves and cycle the pump which pushes out the old brake fluid and draws in fresh brake fluid. If you don't 'test' the brake system the ABS unit will be stewing in old fluid that *may* have moisture contamination and dirt. Not cycling the ABS is not dooms-day stuff. Activating the ABS via wheel lock-up on the road (both front & rear) several times then bleeding again will help a bit. On road ABS activation will short cycle the ABS system whereas the 'test' will activate the ABS long enough to do a full purge.

 

[JimV]

since I don't have a test connector, can anyone who has changed their brake fluid on an ABS model tell me if there is any downside, such as an ABS fault, if you change the brake fluid and don't test the hydraulic unit?

The ABS unit has fluid control valves and a pump. When you do a straight brake bleed it bypasses these items. When you 'test' the ABS system you cycle the fluid control valves and cycle the pump which pushes out the old brake fluid and draws in fresh brake fluid. If you don't 'test' the brake system the ABS unit will be stewing in old fluid that *may* have moisture contamination and dirt. Not cycling the ABS is not dooms-day stuff. Activating the ABS via wheel lock-up on the road (both front & rear) several times then bleeding again will help a bit. On road ABS activation will short cycle the ABS system whereas the 'test' will activate the ABS long enough to do a full purge.

+1

Besides, compared to actually bleeding the brakes, hooking up a jumper and doing the "test" is mouse nuts.

Not only that but sitting still and having the ABS unit firing is kind of fun but not nearly as much fun as doing panic stops to get the front ABS to kick in.

As I recall from the last thread on this topic, the consensus was that the braking system was probably not the one to take shortcuts on. YMMV

Cheers,

Jim

 

[donaldb]

The ABS unit has fluid control valves and a pump. When you do a straight brake bleed it bypasses these items. When you 'test' the ABS system you cycle the fluid control valves and cycle the pump which pushes out the old brake fluid and draws in fresh brake fluid. If you don't 'test' the brake system the ABS unit will be stewing in old fluid that *may* have moisture contamination and dirt. Not cycling the ABS is not dooms-day stuff. Activating the ABS via wheel lock-up on the road (both front & rear) several times then bleeding again will help a bit. On road ABS activation will short cycle the ABS system whereas the 'test' will activate the ABS long enough to do a full purge.

I have a ?

If you bleed the breaks on an ABS bike then activate the ABS a few times to purge and then bleed the breaks again--all together how much break fluid will this process use?

And don't say twice as much

 

[Coyote]

I have a ?
If you bleed the breaks on an ABS bike then activate the ABS a few times to purge and then bleed the breaks again--all together how much break fluid will this process use?

And don't say twice as much

Thanks for asking that question donaldb. It would be nice it the manual gave a step by step on ABS bleeding for peeps like me (hard of understanding). Maybe it does, because I don't read to well either. :blink:

I just want to know how to get all of the old stuff out and new stuff in to all the right places.

 

[ionbeam]

The ABS test tool is a block of 4 pins that has a jumper for 2 pins and two pins that go to 2 connectors that will let you jump power to relays and solenoids for tests unrelated to cycling the ABS pump. The connector that you need to tap into (on Gen I FJRs) is near the battery and you need to take the panels off to access it. The test tool will jump two pins together, then there is a convoluted sequence between the ignition key and brake levers to activate the pump. You will displace 60 CCs (3.7 ci) of fluid through the ABS hydraulic unit. It's all in the FSM.

You should be able to make your own jumper. Let the adventures begin...

 

[donaldb]

The ABS test tool is a block of 4 pins that has a jumper for 2 pins and two pins that go to 2 connectors that will let you jump power to relays and solenoids for tests unrelated to cycling the ABS pump. The connector that you need to tap into (on Gen I FJRs) is near the battery and you need to take the panels off to access it. The test tool will jump two pins together, then there is a convolutes sequence between the ignition key and brake levers to activate the pump. You will displace 60 CCs (3.7 ci) of fluid through the ABS hydraulic unit. It's all in the FSM.
You should be able to make your own jumper. Let the adventures begin...

:huh:

you've lost this low tech rednek

 

[Keith]

Thanks for the information everyone. I guess that including the test procedure to cycle fluid through the hydraulic unit as part of the bleeding process saved Yamaha the cost of installing a bleed nipple on the unit itself.

Keith