1987 brake help

[HespelerC4]

hey there,
i have an 87 with 85k. i lost pedal pressure the other day and brake light came on. if i pump it a few times the pressure comes backa bit but gone as soon as i apply brake. master cylinder reervoir full and no leaks at wheels. i assume the master cylinder is shot and i have ordered one that comes in today. i would love to tackle this myself (withthe help of a friend that works on his own cars. lol) i am a bit nervous about doing it but want to learn.
does anyone agree with my googled master cylinder diagnostic? is there anything else it could be. i would really love to have this fixed for the cambridge corvette show on saturday. could drive it as is i guess but you guys would want me to get there first when the lots still empty. lol
thanks
dave

 

[Riley P]

My best guess would be the piston seal in the master cylinder is gone and letting the fluid back to the reservoir, so I think your googled result is fine.

 

[HespelerC4]

thanks for the info Riley. it looks fairly straight forward. have to take the back wheels off to bleed brakes but hopefully all will work out and i will develop desire and confidence to do some of my own work. bonus side effect of saving money so keeps wife shopping and happy!!!!!!!!

 

[Rowarrior]

yep...master cylinder...been there

 

[Woodstock Car Guy]

Sounds like the right diagnostic. Had it happen to an old Cougar I owned years ago - replaced the master cylinder and it fixed the problem. I hope you get it rolling (and stopping) in time for Saturday's show.

 

[HespelerC4]

manny is going to install the new one for me on sunday so unfortunately the car won't make the show saturday.
i will have to wait till the vette fest in woodstock i guess. i will stop in at show of course then maybe go to the boat.

 

[Woodstock Car Guy]

manny is going to install the new one for me on sunday so unfortunately the car won't make the show saturday.
i will have to wait till the vette fest in woodstock i guess. i will stop in at show of course then maybe go to the boat.

The hardships we must endure ...

 

[HespelerC4]

got my new master cylinder put on by manny on sunday> car stops great now. thanks manny.

 

[Woodstock Car Guy]

So do we get to see your whip in Woodstock this Saturday?

 

[HespelerC4]

yes i will be at woodstock for sure. too bad i missed sat due to the master cylinder but i did have a beauty day at the boat. went for a 5 hour cruise. got stopped by the opp for speeding 70km in a 10 zone. (i honestly didnt see the no wake sign.) no ticket, took pity on my youthful exuberance.
hopefully the weather will hold for sat.