1984 Grand Prix...Help! (AGAIN)

[J-T-]

I bought a 1984 Grand Prix [3.8] with 73,000 miles recently. One owner. Beautiful Car.
Two weeks ago, I got in it to go to work, put it in reverse, and I had no brakes. And the brake light lit up and stayed on. I found out that that the (rubber) brake line on the front passenger side was completely shot. I replaced the line. But I still have no brakes.
I noticed in the brake fluid resevoir that there are bubbles rising when you pump the brake. And the pedal just goes to the floor. And the brake light is still on. Do I need to bleed the brakes? Is there air in the lines? I'm confused... :?:

 

[84GP455]

Is there any brake fluid puddles on the ground?? I bet that you have either a broken brake line, or a broken wheel cylinder. Both of these will leak brake fluid when you step on the brake pedal and will cause your brake pedal to go to the floor of the car, and will turn the brake light on.

 

[midwestls]

Anytime you replace a piece (eg. brake hose/line, master cyl., caliper, wheel cylnder) the holds brake fluid you will need to bleed your brakes. Sometimes you can get away with just bleeding one wheel depending on how much air you go in it. Usually its best to bleed the whole system though. The bubbles your getting out of your master cylinder, are air out of your brake system.

 

[85 Cutlass Brougham]

You will need to bleed the whole system, and not just the one line you replaced. When you broke the other hose, it drained the master cylinder which introduced air into the system. I would also point out that this is a good time to replace the other two hoses too. They will likely fail soon, and probably not at such a fortuitous time.

Anyhow, when you do bleed the system, you should start from the farthest point from the master, and work your way to the closest. ( pass. rear, driver rear, pass front, driver front is the right sequence.)

 

[shotgun]

Read this. http://gbodyforum.com/viewtopic.php?t=5203&highlight=

 

[J-T-]

I would also point out that this is a good time to replace the other two hoses too.

What other two hoses? Sorry, i'm not sure exactly what you mean.

I'm going to replace the front driver side (rubber) line because I'm sure it's only a matter of time before that fails as well.


Thank you to everyone who posted a reply. I really appreciate it. 😀

I have received the same advice (bleed the entire system) from a few other people as well.

I'll let you know how it goes...

 

[85 Cutlass Brougham]

There are 3 hoses in a G body disc/drum braking system: 1 on each front wheel, and one for the back axle. After 20+ years of abuse, rubber parts deteriorate pretty badly and should be replaced. I would also check the condition of the fuel lines at the gas tank while you are back there, and the fuel line to fuel pump hose in the engine bay. It would also be a good idea to replace most of the vacuum hoses under the hood too. While you are there, check all of the coolant hoses for condition. You really don't want any originals still on the car after all these years. This is all just basic old car maintenance stuff that needs to be gone over to ensure safe, reliable operation.

 

[moparguy10]

Having just replaced brake hoses on my '83 Grand Prix, i can advise to use plenty of rust penetrant or WD40 on the brake line connections. I managed to twist off the metal line as it was rusted to the ferule (sp?). Brake fluid will always find the weak spot. Take a look for rusted lines that connect between the master cylinder and all four wheels. Welcome to the G-Body Forum. Lots of good information here.

David

 

[J-T-]

After bleeding the entire system and replacing the driver side brake hose, there is still air bubbles appearing in the resevoir. One person said that the seal in the master cylinder is most likely shot and that it should be replaced... grrrr...

 

[J-T-]

Hmmm...

Alright, I got the brake problem diagnosed and fixed. It was the passenger side caliper. The bleeder screw got messed up and I had to replace it.

New problem/question: I noticed a small puddle underneath my fuel tank this morning and fuel is dripping from the surface of the tank. I drove it home and when I parked the car I got out and looked underneath. Fuel was slowly dripping from the steel line that goes into the tank. I parked it in a different place and now it's dripping from the surface of the tank again.
Is this most likely the fuel line or the tank that needs replacing? I'm guessing it's the fuel line but do I need to go to a salvage yard for something like this?

I would also check the condition of the fuel lines at the gas tank while you are back there, and the fuel line to fuel pump hose in the engine bay. It would also be a good idea to replace most of the vacuum hoses under the hood too. While you are there, check all of the coolant hoses for condition. You really don't want any originals still on the car after all these years. This is all just basic old car maintenance stuff that needs to be gone over to ensure safe, reliable operation.

Good call!