84 GN Braking Problem..

[91rangerturbo]

I have a 84 GN and took it for the longest drive so far the other day. It was about one hour. And i was pulling in there was some traffic that i had to sit through for about 15 mins.

My brake pedal went to the floor. I pumped it up and it started working again but will not hold constant pressure. It like it is bleeding off because a blow seal or something and the (idiot) brake light on the dash came on.

I topped the master cyl. of with fluid and pumped the brakes again. But it still isn't hold like before.

My first thought was the wheel cyls in the rear but everything looked dry and no serious leaks i could spot with my eyes. What would be the first thing to check? And what kind of brakes did the older 84 GNs have vacuum brakes?

Any help would be appeciated because i will be address this problem tonight.

[onefastcar]

if it's a powermaster



http://www.gnttype.org/forums/showthread.php?t=3505
if its converted to a vacuum set up i'd say a booster is bad.

[84GNGary]

It should be a hydroboost with a master cylinder. If that is what it is it's just like a conventional braking system and the same symptoms and fixes would apply. The only thing different is that there is a plunger that comes out of the hrdrobooster and pushes against the master cylinder when the brakes are applied. This can be seen if you unbolt the master cylinder from the hydrobooster and apply the brakes lightly.

[91rangerturbo]

Looks like i have a wheel cylinder leaking on the passenger side rear. I am fixing that tonight.

[91rangerturbo]

fixed the wheel cylinder last night and it still did not fix the problem.

[91rangerturbo]

I got around to replacing my master cylinder last night. I have brakes again.