SwedeSpeed - Volvo Performance Forum banner

1 - 7 of 7 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter · #1 ·
I recently replaced the hydraulic brake hoses on the front of my 2003 S80, installed new rotors & pads and bled the system using the RR, LR, RF, LF pattern. I am still finding that the brake pedal is spongy indicating that air must still be in the system.<p>I am concerned about possible air being trapped in the ABS unit. Is there a special procedure or bleeder on the ABS system that I am missing in the bleeding process? Any help here is appreciated!
 

·
Registered
Joined
·
193 Posts
Re: Bleeding 2003 S80 brakes (IRolled2)

Did you use a power bleeder and set a high enough psi? or did you use the 2 man approach. I see you said you replaced your brake hoses, pads and rotors. You may have done the procedure correctly but the pads and rotors arent worn in correctly yet. I only bled my brakes with replacement of the front brake hoses and it was fine. <p>When i did just a pad change i noticed that for a while it would feel spongy and not grip enough. Thats just cause the pads didn't adjust to the rotors. Maybe you just haven't driven enough yet. <p>Btw, i believe if the brake pedal doesn't just drop and is gradual, but spongy, then its probably just the wearing in.
 

·
Registered
Joined
·
56 Posts
Re: Bleeding 2003 S80 brakes (IRolled2)

<U>From VADIS:</U><br>Preparations<br>Switch off the ignition.<br>Clean around the brake fluid reservoir filler cap.<br>Take out the container.<br>Remove the filler cap.<br>Fill the brake fluid reservoir completely.<br>Raise the car<p><br>Bleed left front wheel<br>Note! While bleeding, check that there is sufficient brake fluid in the reservoir. Top up if necessary.<br>Remove the protective cap from the bleed nipple. Connect the hose from the collection bottle.<br>Depress the brake pedal a few times. Maintain pressure.<br>Open the bleed nipple.<br>Depress the pedal fully. Keep it fully depressed for approximately 5 seconds. Release it again. Repeat this 3–5 times until there are no air bubbles in the fluid coming out of the hose.<br>Tighten the bleed nipple.<br>Remove the hose from the bleed nipple. Install the protective cap.<br>Continue bleeding the other wheels in the same way in the following order: <br>Right front wheel, left rear wheel and right rear wheel.<br>Checking for air in the brake system and for brake fluid leakage <br>See Brake pipe master cylinder / ABS unit, replacing <p>Note: This shows essentially opposite sequence of what I have seen and learned in the past....
 

·
Registered
Joined
·
193 Posts
Re: Bleeding 2003 S80 brakes (dcarlson12)

I'm sorry but that VADIS instruction must be a mistake. That is against physics right there. Everyone knows you start from the furthest wheel from the reservoir. And i'm pretty sure he did it right, just like i said the brakes have to wear in. He hasn't written back in a while he probably figured it out.
 

·
Registered
Joined
·
56 Posts
I sent an email to the Global Customer Relations department in Sweden but just got the 'Contact your local Dealship for technical information' reply; talk about getting the run around. So I forwarded the email to a local dealer. <br>Was really surprised when the Service manager called me. He said it makes no difference what order one uses. Said the RR, LR, RF, LF front applied only to 'older' cars. Didn't really try to explain any logic. I would like someone like to explain the logic for either method. Said it applied whether one was bleeding the air or replacing old brake fluid with new. My logic would say that one should start with closest bleeder to the master cylinder in order to ensure that if any fluid were to be carried to the further down stream locations then the fluid should be clean from the master cylinder to the closest bleed point and then the next closest and so on. I am willing to hear about other logical reasoning.
 

·
Registered
Joined
·
3 Posts
Discussion Starter · #6 ·
Re: Bleeding 2003 S80 brakes (POLSKA)

I've driven the car for about 3 weeks now and the brakes have not worn in, so there must still be air in the brake lines. While bleeding the RR line (which I did first) it sounded like valving was occuring in the ABS unit every time I bled the line (using the 2 person method). This stopped by the time I got to the 2nd wheel (LR).<p>I have since bought a mity-vac and plan to power bleed the brakes in the near future. I'll keep you all posted.
 

·
Registered
Joined
·
1,055 Posts
Re: Bleeding 2003 S80 brakes (IRolled2)

IIRC there's a electric vacuum pump which runs when the brake pedal is depressed to maintain power assist of the service brakes. It only runs when the ignition is switched on or for a short spell after the ignition is switched off and the key removed from the ignition.<p>All said pump does is provide extra vacuum to work the power brake booster. It doesn't directly deal with ABS nor the hydraulic side of the service brake system for that matter.<p>If air has migrated into the ABS HCU then the easiest remedy is to swing by the local Volvo dealer and have them bleed it. The bleeding process isn't DIYer friendly.
 
1 - 7 of 7 Posts
Top