I swapped a new rear-end into a '91 240. This meant that I had to remove the brake lines and thus bleed the whole system. Now when I try to bleed it, the brake pedal never gets solid. I seem to be getting pressure at all wheels and the air out of the lines, but when I press the pedal, it still goes all the way down to the floor.

Did my master cylinder go bad during the bleeding process? I followed the bleeding order described in the Haynes manual.

 

How many bleed nipples on the front calipers? Some of the Girling calipers fitted to Volvo have three. On these all three bleed nipples have to be open at the same time.

 

My front brakes do have 3 bleeding valves on them. According to the Haynes manual, the bleeding order is:

Left-Rear
Left-Front-Top
Right-Front-Top
Right-Rear
Right-Front-Bottom-Outer
Right-Front-Bottom-Inner
Left-Front-Bottom-Outer
Left-Front-Bottom-Inner

This is the order which I used. It doesn't say anything about opening all 3 on a caliper at once.


I was still concerned about the master cylinder so I found instructions online that explained how to bleed it. I removed the brake lines from the master cylinder and plugged them. Then I jacked the car up until the master cylinder was level, topped off the fluid and worked the brake pedal slowly about 1/2 to 1" until it was firm. At this point the pedal was would go about 1/2" before it was solid. This would tell me that the master cylinder is not the problem. However, when I hooked up the lines and did a pressure bleed on the whole system, very little air came out but the pedal again goes to the floor.

It seems that there is still some air in the system but I have no idea where it may be hiding.

Any ideas out there?

 

After a double check on the Haynes manual, it does indeed state that the lower inner & outer bleed valves should be opened together. I'll give it another try tomorrow.

Thanks for the help.

 

That comes from a Volvo publication. Haynes is usually good, especially for older cars but mine does not mention the 3 valve caliper at all, so possibly it was an oversight.

 

Well, I re-bled the brakes - this time opening the two lower valves at the same time when bleeding the front brakes. No air came out at all.

Re-checked the master cylinder to make sure no air was in it. It is still solid when I plug the lines.

It seems that there is air lurking in the system somewhere but I am at a loss to find it. I had pretty much drained the entire system so I am wondering if there is any special procedure for bleeding a system that was dry. Anyone out there know?

 

I think I have found the problem. Makes me feel like such an idiot. When I swapped the rear end, I installed the rear calipers on the wrong side! This puts the bleeder valve on the bottom. Of course this leaves a big bubble behind the piston.

Tonight I'll switch them and see what happens.

Thanks for all the input.