1998 s70 replacing brake lines, need some advice!

[JRev]

Cheers for the replies but i bled the system from the new caliper and pedal was still mushy, still a hiss noise so that may well be the brake booster.

Also the other calliper had its bleeder screw missing so I couldn't do all four corners as I tried what abscate suggested and tried to bled via the hose, which was messy but pedal was still mushy.

I'm going to replace the other rear calliper (it needs replacing anyway), also make a calliper hard line and new hose and then flush the system with new brake fluid.

I also have to fix the ABS/Tracs light as the car won't pass an MOT (in the uk) with the light on, even though the lights turn off after 20mph, been intermittent issue now for few months.

Appreciate all the advice so far.

[JRev]

I found this video on YouTube



This is exactly how my pedal reacts with the hiss when the guy starts the engine, but if the pedal is stiffer (there is no hiss) so I'm hoping that once I bleed the system properly and the pedal is firm, then its ok, as I've always had a firm pedal, which means I wouldn't have noticed any hiss before.

Unless that hiss shouldn't happen regardless?

But I will update this when I complete all the work (which will be before Christmas )

[abscate]

Cheers for the replies but i bled the system from the new caliper and pedal was still mushy, still a hiss noise so that may well be the brake booster.

Also the other calliper had its bleeder screw missing so I couldn't do all four corners as I tried what abscate suggested and tried to bled via the hose, which was messy but pedal was still mushy.

I'm going to replace the other rear calliper (it needs replacing anyway), also make a calliper hard line and new hose and then flush the system with new brake fluid.

I also have to fix the ABS/Tracs light as the car won't pass an MOT (in the uk) with the light on, even though the lights turn off after 20mph, been intermittent issue now for few months.

Appreciate all the advice so far.

The system self tests at that speed and the fact that the light goes out means it's working. Hmmm strange.

[JRev]

Success!

We have a firm pedal and no leaks.

I also ended up replacing the offside brake line which runs to the abs unit.

Had slight trouble with bleeding at first as I was doing gravity bleeding but made the mistake of not submerging the tube into the brake fluid as I made my own kit using clear tubing and an old coffee tub, but bleed again and this time I saw bubbles appear and as the tubing was submerged in the old fluid, then air couldn't return to the caliper.

Anyway, many thanks for all the advice as quite pleased with the job i've done considering this was my first big project on learning about cars.

[JRev]

Cheers for the replies but i bled the system from the new caliper and pedal was still mushy, still a hiss noise so that may well be the brake booster.

Also the other calliper had its bleeder screw missing so I couldn't do all four corners as I tried what abscate suggested and tried to bled via the hose, which was messy but pedal was still mushy.

I'm going to replace the other rear calliper (it needs replacing anyway), also make a calliper hard line and new hose and then flush the system with new brake fluid.

I also have to fix the ABS/Tracs light as the car won't pass an MOT (in the uk) with the light on, even though the lights turn off after 20mph, been intermittent issue now for few months.

Appreciate all the advice so far.

The system self tests at that speed and the fact that the light goes out means it's working. Hmmm strange.

Its really annoying as I was aware about the self test and the abs/tracs light is now on but if I drive up my driveway, the light is off (after 20mph) and then it returns again!

Unsure what to do, as should I replace the abs unit? sensors? as need to solve this issue so I can get a yearly mot ticket, as the testing station will fail the car if the light is on.

[JRev]

Here's a photo of the work I completed on the front, just incase this thread is viewed in future to show that you can do this job yourself, without needing to pay a garage or buy expensive tools.

The pipes at the front were all bent using a whisky bottle or by hand (thumb) and one tip is to keep the old pipe your replacing and bend it match by using cable ties to join the pipe together while you bend the new pipe, using the old pipe as the template.

[scot850]

Well done and thanks for the write up! Having had a lot of fun with the rear end AWD brakes and bleeding the system, I feel your pain.

Neil.

[JRev]

Ha Thanks Neil. Someone at Volvo owes us a beer (or 2).

The way I bled the brakes was gravity bleeding. Had the car on 4 axle stands, filled up from master cylinder, pumped the brakes slowly about 5 times. Then starting with rear right, let gravity do its thing (with a pump of the pedal if needed) and if required re-bled all corners and brakes feel great.

I did read up about some never getting the bleeding process right, but the gravity method worked best for me.

Cheers - John

[scot850]

Worked for me also doing the same as you except I started at front LH and worked to RH rear last (as per Volvo Vida instructions). Again no pressure bleed system, just my son, me and a piece of pipe in a jar of brake fluid at one end and the other end of the pipe on the brake nipple. Like you say, I think the secret is taking your time, and expect you may have to bleed each corner more than once.

Neil.

[JRev]

Thought I should update this thread as I never uploaded a photo of the rear brake line that I scraped and done again, as I wasn't happy about the bends I made and as my exhaust tip recently fell off after a long run on our great roads which have potholes every 10 metres!, I took some pics.

Heres my exhaust tip which I clamped onto the original exhaust.



But more importantly for this thread, two pics of the rear line as I never went the exact original route, instead ran it neatly along the top of the cross member and one tip is in the final photo you will see i wrapped part of the brake lines with silicone tubing and secured with cable ties, just to prevent any possible damage to the line.