Tested that, there isn't any difference to the brake pedal if the engine is on or off...o_O

I'm beginning to think it is probably best to purchase a new servo and new single line master, and redo it completely

Taken the pipe off, good suction to the servo, so either the one way valve has gone or the servo gone. Brakes work To a certain extent, but you have to drive it like the QE2 and brake 3 miles before you want to stop whilst standing on the brake pedal. The master cylinder is clearly not right as...

Thanks for all the responses, looking closer it is obvious that they have chopped out some bodywork to fit the larger servo in. The brakes don't work at all, the pedal is solid, hence looking at the servo to replace it.

Well yes it does, which makes me think that it is a single line, but who ever had it before put the wrong master on it, and put both lines going into one?

Built in 1977, it has two outlets in the master, then t's up into one, which as far as I can see is pointless....

hello, i'm new to all this, and need some help to understand if my series 3 (109") has a dual line or single line brakeing system. it has a dual line master cylinder, but then going into a single line shortly after. see attached photo.