master cylinder ??

[janbardy]

hi all, brakes have gone to pieces, i can almost get pressure on the brake pedal by pumping it 5 or 6 times but only when the engine is not running , if i pump the pedal ,get pressure , then start the engine the pedal sinks to the floor.....hmmm time for a master cylinder rebuild do you think ?   

[Wayne]

Sounds more like a servo problem.

[janbardy]

is there any way of isolating anything to check if it is the servo, as i am in australia and spares are pretty hard to come by and pretty exy to, i have managed to find a master for about 200 bucks but not a servo yet , by the way it is a 1990/1 mk1 cabby with eng no.JH382080, thanks

[Wayne]

If the pedal is sinking to floor when you start it then to me it is your servo.

[janbardy]

so the mk2 gti m/c and servo should fit on pretty straight forward you reckon

[rubjonny]

yep, what you do is swap the mk1 servo clevis pin onto the mk2 one, yopu'll have to cut the thread down on the MK2 servo though. you measure the distance between the mounting face and the clevis pin hole, then match this on the MK2 servo. I found on mine that meant you had to thread it on all the way