3 replies to this topic

[s140s]

Hey guys, not a big poster on this site but some may recall me over on SS. Im having an issure with the hydraulic system on my R but lets start from the begining. In December I bought my 2nd R but this one had a blown engine. I have taken everything apart, and put another engine in. I have replaced the slave/air vent/clutch/press plate while in there. I got everything back together and the engine started on first try. The issue I am having is I can not get a solid brake pedal. If I pump it up and stay on it, the pedal is firm but as soon as I release it, wait 2-3seconds and press it again, once again it just drops to the floor. When the pedal drops to the floor, I hear the brake vacuum pump turning ON and OFF, it making a buzzing sound(located under the airbox, mounted to the chassis) I've spent many many hours bleeding the system, using gravity method, 2 men, vacuum through bleeders, and power bleeding. There is definitely NO AIR in the system. I did go in proper bleeding order RR, RL, FR, FL, Clutch. When I had the Power Bleeder connected and pressurized the brake pedal was solid hard all the time. Another issue I am having is, the clutch is not disengaged fully with the pedal to the floor(very little drag), but there is engagement/disengagment when using the clutch pedal. I hope someone might know where I effed up, this is not my first time working on Volvo's/ cars since I had an R in the past, and have also done engine work on 850's but I have a bad feeling I done something incorrectly.


Any clues?

Master Cylinder internal leak?

Sorry for any grammar, its a lot of text to wring on a cell phone.

[Ihatespeedbumps]

I would try reverse bleeding at the slave cylinder with an oil can filled with brake fluid. Search this site for clutch bleeding, I've posted it quite a few times. On mobile or I'd search myself.

[s140s]

Done that as well, If there is still any air in the system then I will call this car a MacGyver. I will estimate about 10hrs of bleeding by this point and fluid pours super clean, no bubbles or any traces of air.

[Ihatespeedbumps]

Internal leak in the MC is always a possibility, and not uncommon in this chassis.

When I replace the MC, I don't bench bleed, rather have someone pump the pedal while I crack the lines open at the MC, then move on to bleeding the wheels.