Ok, I've had a number of 200B coupes over the years, all with various brake upgrades from Magna Rotors up front with commo calipers and std drums, to Volvo Girling 4 spotters and std drums, and now lately to the volvo 4 spotters and R31 rear disks.

All these set ups have had the 7/8 master cylinder.

The issue I am having is that I always have to do at least 1 pump (usually 2) of the pedal to get any decent braking or feel. Otherwise it goes down too far. Is it just my bleeding technique leaving air in the lines somewhere or does the SSS booster have something to do with it?

I bleed the brakes so that no spurts or splatters come through and I start at the LH rear 1st, then the RH rear, LH Front and finally RH front. I also bleed the master cylinder in between these. I also don't jump on the pedal when bleeding. Just a reasonable amount of pressure applied. Could my bleeding order or technique be the trouble?

What about the booster? When the brakes on these cars are not touched the pedal is nice and firm gives excellent feel. Its only when something is upgraded that this spongey pedal becomes the issue. Remember this is acrross a number of SSS's and not just the one car.

Any feedback?

Regards Scott.

I thought you were meant to bleed the master first,then go from Lhr. I could be wrong though. Unless the booster is faulty (that'd be weird though if it's happened on a few cars) i doubt the booster would be the problem.

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i have the same problem, i also use this technique to bleed brakes and no matter what car i do it on the brakes are always slightly spongy.

what else can be done?? do mechanics use this technique or some other way??

ive seen power bleed kits, but i think they are just so you can do it with one person.

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When the sign says "don't feed the bears", man you better not feed the bears.

Master cyl is bled first (if it's been disconnected), then each wheel: furthest to closest.
When bleeding the calipers, it helps if you give a few pumps on the brake pedal when the bleed nipple is closed. This pushes any air through the lines and into the calipers.
Also, don't release the brake pedal until and bleed nipple is closed off. To be extra sure, the nipple can be closed before the brake pedal bottoms out. This way there is no chance of any air getting back into the caliper.

At work we use a brake bleeder bottle that connects to an air line. Vacuum sucks the brake fluid through the system. We also have a pump for Euro cars that forces fluid in through the reservoir. When I worked at Honda we also used the 2 person method.
I've also heard of the gravity method. Wouldn't use it myself, I don't think it would be effective at purging air. Just to flush the brake fluid might be ok.

Aside from that?

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Rod

ive actually got to do my n13 pulsar today.

but from what ive read here its already what i do, appart from maybe shutting the bleed nipple of before the pedal touches the floor. ill see how i go but not expecting any different results.

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When the sign says "don't feed the bears", man you better not feed the bears.

Do you use a jar full of fluid with a hose over the nipple going into the fluid to stop air going into it?

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Thanks for all the replies. They have been great.

I did a bit of research and realised I should check the booster pushrod into the back of the master cylinder clearance. I had approx 2mm gap! So with a bit of white paint pen on the push rod, I adjusted and refitted the master cylinder multiple times, adjusting the pushrod each time until I got a little bit of white paint on the master cylinder itself. I then backed off the booster a touch and refitted the MC.

I then tried a different approach at bleeding. Yes I bled the MC 1st, then went LHR, RHR, LHF and RHF for bleeding order as normal. The only thing I changed was I got my wife to give the pedal a few good pumps between each bleed and hold more pressure on the brakes for each bleed off.

All I can say is what a difference! No doubt the Booster to MC clearance played a part. But I'm sure the change in bleeding tecnique was the big player.

Brakes are beautiful! Nice firm pedal and I require no pumping in between.

Oh and yes I always use a jar with fluid in it for bleeding

Thanks again all.

Booster to M/Cyl clearance makes a bigger difference than
you would expect.

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A little knowledge is a dangerous thing.
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