I have a 1990 240 DL wagon, and the brakes are not abs. My son has been driving it for the last four years, and he said it still stops, but the brake light is on, and the system has some air in it. Pedal does not go all the way to the floor, but it is spongy. Opened the hood, and the master cylinder reservoir front part is full, but the rear part closest to the firewall is empty. Master cylinder only has one fill hole, so I don't understand why the rear reservoir is staying empty.

I can't get the master cylinder full of fluid by just filling the master cylinder, so I don't know the best way to proceed. Looked up under to see if any brake fluid trails was present at the wheels, and I don't see any. I think the master cylinder is bad, or the brake junction box is bad too. Going to buy a Motive brake bleeder to bleed the brakes. Let me know what you think the problem is, and how to diagnose this problem.

 

Ok I was not topping of the fluid enough because these Volvo reservoirs have to be filled close to the top before the fluid starts flowing to the rear reservoir. Chalk that one up to a learning experience.

 

if the brake fluid was low, you either have a leak somewhere, or your brake pads are at their end-of-life, and when you install new pads, the pistons will push the fluid back out to the reservoir, causin git to overflow.

hmmm, 4years, its overdue for a brake fluid flush. but its probably overdue for a full brake job, or at least inspection.

 

i can say that it was well worth it to replace all 4 rotors pads including e-brake shoes and hardware. i went with meyle rotors and bosch/volvo pads/meyle shoes. rebuilt ate a1 cardone calipers on the rear. i was not sorry the car brakes like new.

 

the best brake setup I've had yet on any RWD Volvo is the Brembo rotors + PBR pads currently on my 740T wagon... The wagon stops almost as well as the couple Mercedes W124 300E/E320's I have (the benzes have just amazing brakes and suspension).