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Flatheadfever
06-02-2018, 11:48 PM
I replaced my rear brake line and proceeded to bleed just the rear lines at the calipers. Iím having no luck getting all the air. Do I also need to bleed both front lines as well? Or there some other trick that I am missing?
Thanks 2006 2500 118Ē sprinter

CJPJ
06-03-2018, 01:07 AM
I like and use the vacuum bleed technique. And I would bleed all four calipers starting a the rear furthest from the reservoir.







http://www.sprinter-source.com/forum/showpost.php?p=314762&postcount=1

lindenengineering
06-03-2018, 01:32 AM
I replaced my rear brake line and proceeded to bleed just the rear lines at the calipers. Iím having no luck getting all the air. Do I also need to bleed both front lines as well? Or there some other trick that I am missing?
Thanks 2006 2500 118Ē sprinter

Question?
Did you hold the brake pedal down with a prop of some sorts to stop the reservoir leak down through the open connection to depletion during the pipe change?
If you didn't follow that then you have certainly emptied the Master cylinder most likely on both sections no doubt .
At this stage you MUST go easy with pedal depression because you can easily damage a delrin forked sleeve in the servo that operates the master cylinder plunger then you will never get a brake without changing the servo assy .
So caution!
My suggestion is to do a gravity bleed FIRST .
In a normal bleed procedure open each bleeder in turn with a full reservoir, then observe the drip of fluid out of the caliper until approximately 1/3rd of reservoir has gone down. Seal off & repeat for each caliper & then at that stage you should have "a pedal feel " and then bleed in the normal way.
Of course in the Pro shop scenario we use a scanner to artificially operate the ABS brick but you can do that by making the system work on some rough loose surfaces doing vicious braking techniques if necessary .
All the best & good luck.
Dennis

Flatheadfever
06-03-2018, 10:26 AM
Thanks Dennis,
I really appreciate your help. You deserves all the credit for info you gave me last summer with my head gasket replacement.
I probably need some luck like now as I did drain the master cylinder and I let gravity help fill it but then could get the air out with 2 people do a traditional type pump hold and bleed.
I put the rear wheels on and when down the gravel road, at slow speeds I had pedal with a couple pumps but once I got rolling it felt like the abs pulsating the brakes.
I may have buggered up the servo, I’ll gravity bleed the front and go from there.
Thanks again.

lindenengineering
06-03-2018, 11:45 AM
Thanks Dennis,
I really appreciate your help. You deserves all the credit for info you gave me last summer with my head gasket replacement.
I probably need some luck like now as I did drain the master cylinder and I let gravity help fill it but then could get the air out with 2 people do a traditional type pump hold and bleed.
I put the rear wheels on and when down the gravel road, at slow speeds I had pedal with a couple pumps but once I got rolling it felt like the abs pulsating the brakes.
I may have buggered up the servo, Iíll gravity bleed the front and go from there.
Thanks again.

Well thanks for the note on your past head gasket repair
Here's a suggestion' this often works at a pinch .
Re-bleed the brakes again in the normal way---BUT! Get an assistant to pump the brakes up so that you have a really hard pedal--hold the pressure---- then release the bleeder to blast the fluid out..
Do this about 5 times a caliper.
It also is beneficial to jack the van up as high as you can get in at the rear, use some stands for safety . This aids bleeding the master cylinder as air will naturally float out of the master cylinder and into the reservoir (a mid 1980's Ford Taurus technique--buggers to bleed out for a good pedal)
Try those techniques first.
All the best
Dennis

Flatheadfever
06-09-2018, 10:16 PM
Question?
Did you hold the brake pedal down with a prop of some sorts to stop the reservoir leak down through the open connection to depletion during the pipe change?
If you didn't follow that then you have certainly emptied the Master cylinder most likely on both sections no doubt .
At this stage you MUST go easy with pedal depression because you can easily damage a delrin forked sleeve in the servo that operates the master cylinder plunger then you will never get a brake without changing the servo assy .
So caution!
My suggestion is to do a gravity bleed FIRST .
In a normal bleed procedure open each bleeder in turn with a full reservoir, then observe the drip of fluid out of the caliper until approximately 1/3rd of reservoir has gone down. Seal off & repeat for each caliper & then at that stage you should have "a pedal feel " and then bleed in the normal way.
Of course in the Pro shop scenario we use a scanner to artificially operate the ABS brick but you can do that by making the system work on some rough loose surfaces doing vicious braking techniques if necessary .
All the best & good luck.
Dennis
Dennis,
I had to walk away from the van and go back to work. I will nit be able to do anything until i get home in 3 weeks.
I had a chance to vacuum bleed both front brakes. I used an old air conditioner vacuum pump and I was able to pull 300- 500cc or so through each caliper and watch the fluid as it came out. No sign of any air bubbles but the fluid was dirtier than what was going in. I had no one at the time to assist me with a proper bleed. The result was still no peddle on the first pump and after a few pumps it would be hard but then slowly bleed off to the floor.

Do you think I trash the servo? Or maybe need to do a better bleed when i get home. I donít mind ordering a servo when Iím away and then it at least it will be there when i get home.
Thanks

Aqua Puttana
06-10-2018, 12:49 PM
I'm not Dennis.

... Or maybe need to do a better bleed when i get home.
...
Thanks
Blindly swapping parts doesn't come without possible pitfalls.

I would try a better two person bleed procedure. If the CAB aka ABS brick hasn't been activated there shouldn't be air that can't be bled out using normal bleed procedures.

:2cents: vic

Bobnoxious
06-10-2018, 01:01 PM
So, the two-person pump, hold and crack open the wheel cylinder/caliper valve method works on ABS?

Aqua Puttana
06-10-2018, 01:17 PM
So, the two-person pump, hold and crack open the wheel cylinder/caliper valve method works on ABS?
That method has worked fine on my CAB aka ABS equipped 2004 and 2006 for various brake service and line/caliper changes.

vic

Flatheadfever
06-10-2018, 10:34 PM
That method has worked fine on my CAB aka ABS equipped 2004 and 2006 for various brake service and line/caliper changes.

vic

A couple of mechanics I know said the AbS feature should not affect anything. I will have to corner somebody to help me with a double person bleed. The vacuum pump pulled the fluid through quickly I thought for sure I had it done. I thought of buying a brake booster as it will probably take a week or two to have one shipped here and I am only home for 3 weeks and would like to do some traveling with the van when home.

Bobnoxious
06-10-2018, 10:54 PM
I purchased an apparatus similar to this and have not used it, yet. Hope it works as advertised.

Midwestdrifter
06-11-2018, 12:06 AM
For routine fluid replacement, I find gravity bleeding works well.

Mike DZ
06-11-2018, 12:57 AM
I purchased an apparatus similar to this and have not used it, yet. Hope it works as advertised.

I've used that tool successfully, sure you will too.

Bobnoxious
06-11-2018, 02:15 AM
For routine fluid replacement, I find gravity bleeding works well.

I didn't know. Short peddle travel like Dennis suggested. Works with ABS?

https://m.youtube.com/watch?v=U_7bPdeh_jM#searching

Midwestdrifter
06-11-2018, 04:09 AM
If you are replacing the fluid on a regular schedule, the small amount in the abs module is not a problem. For systems than have been neglected, a power flush, and abs activation may be called for.

Aqua Puttana
06-11-2018, 11:57 AM
If you are replacing the fluid on a regular schedule, the small amount in the abs module is not a problem. ...
I agree for FWIW. We get icy/slippery conditions in my area. I know that the CAB pump operates and circulates the fluid occasionally during those times.

The old style two person pump up works fine. All that you need is a friend or a wife in your life. "Pump it up Honey... hold... pump again... ". It can be an excellent bonding moment.

It ain't rocket science.

vic

Bobnoxious
06-11-2018, 12:08 PM
I agree for FWIW. We get icy/slippery conditions in my area. I know that the CAB pump operates and circulates the fluid occasionally during those times.

The old style two person pump up works fine. All that you need is a friend or a wife in your life. "Pump it up Honey... hold... pump again... ". It can be an excellent bonding moment.

It ain't rocket science.

vic

I have employed the same "old style" method and wonder what the neighbors think.

Flatheadfever
06-12-2018, 12:03 AM
I agree for FWIW. We get icy/slippery conditions in my area. I know that the CAB pump operates and circulates the fluid occasionally during those times.

The old style two person pump up works fine. All that you need is a friend or a wife in your life. "Pump it up Honey... hold... pump again... ". It can be an excellent bonding moment.

It ain't rocket science.

vic

I did that for rear. And still had air. The front I pulled fluid through with a vacuum pump and it didnít improve. I may have an airlock in the rear of the master cylinder.

Aqua Puttana
06-12-2018, 12:15 AM
I did that for rear. And still had air. The front I pulled fluid through with a vacuum pump and it didnít improve. I may have an airlock in the rear of the master cylinder.
:idunno:

I would begin in the front. I always start bleeding with the shorter lines and work to the longer lines.

It can take some pumping cycles when using the old method. One modified method is to keep the brake bleeder hose immersed in a clear container of brake fluid to watch for bubbles. Keeping the hose immersed also can help avoid sucking air back if re-closing the bleeder is slightly delayed.

:cheers: vic