Welcome Guest [Log In] [Register]
Posted ImageWelcome to the all new Geo Metro Forum. We hope you enjoy your visit.

You're currently viewing our forum as a guest. This means you are limited to certain areas of the board and there are features you can't use and images you can't see. Registration is simple, fast, and completely free. If you're already a member please log in to your account to access all of our features:

Join our community!




Username:   Password:
Add Reply
Poor Braking Performance; Low brake pressure
Topic Started: Jan 4 2011, 09:48 PM (2,995 Views)
rcdraco
New Member
[ *  * ]
In response to 944door: I personally bled each wheel until the fluid was clear. The shoes were put on about a week later.

The only leak was a front brake hose, so those were replaced, fluid level has stayed high since. I think I'll try that though and replace the rear hoses as well, the car is nearly 16 years old they might as well be changed.
Offline Profile Quote Post Goto Top
 
944door
Member Avatar


So Id almost guarntee its the master cyl thats the culprit. If the rear brake hoses are clogged the pedal would be stiffer. It would only go to the floor if:

1: Air in the system (which you have ruled out)
2: A leak somewhere in a line, porpotioning valve, or hose (which has been ruled out)
3: A bad master cyl (yet to be ruled out)

:thumb

If fundage is short go to a salvage yard in search of a lower mileage Metro and snatch the master, they are simple enough to change.
Offline Profile Quote Post Goto Top
 
rcdraco
New Member
[ *  * ]
So it can't be the brake booster itself though, right? I have a feeling that I might be better off changing both, the booster's surface is entirely corroded, and for the cost of both the job ends at like $100 plus a set of wrenches. (I work at an autoparts store, get a pretty good discount :P)
Edited by rcdraco, Jan 5 2011, 09:07 PM.
Offline Profile Quote Post Goto Top
 
944door
Member Avatar


rcdraco
Jan 5 2011, 09:07 PM
So it can't be the brake booster itself though, right?
If it was the booster going bad your pedal would be hard as a rock. Sand paper and flat black spray paint do wonders as long as the booster is not rusted through. Also in some cases when the booster fails it causes a major vacuum leak.
Edited by 944door, Jan 6 2011, 08:55 AM.
Offline Profile Quote Post Goto Top
 
Bad Bent
Member Avatar
Facetious Educated Donkey

I just repaired the brakes on my friends '92 Nissan Pathfinder.

His issue was the pedal going all the way to the floor. Virtually no resistance.

I saw a brake fluid leak at the Master Cylinder (MC) and brake booster joint. His MC looks like our only larger :lol . Click for pic.Apparently there is a very thin layer of gasket between the two that eroded. I disassembled it, cleaned the MC and used RTV on it when I put it back together. There may be a leak at the LF brake nine/hose. :(

Good news is that my friend drove to work today and did not loose his brakes and wind up in a fiery crash. :lol In the next few days we'll see if it is the brake line leaking also. :-/
Offline Profile Quote Post Goto Top
 
jonathan180iq
Member Avatar
Not Really All That Smart

Do you lose fluid over a short amount of time? Check for leaks in the system

Just based on what you've already said, I'd say it's definitely ther master cylinder. Just grab one from a junker and replace the whole thing.
Offline Profile Quote Post Goto Top
 
rcdraco
New Member
[ *  * ]
I am confused though how it's not giving the tell tale symptom, it just seems like it's tired. Can it wear out just from the previous owner thinking brake fluid was a lifetime fluid. :P
Offline Profile Quote Post Goto Top
 
944door
Member Avatar


rcdraco
Jan 6 2011, 11:07 PM
I am confused though how it's not giving the tell tale symptom, it just seems like it's tired. Can it wear out just from the previous owner thinking brake fluid was a lifetime fluid. :P
:shit Breaks plain and simple. With older cars like these parts can go bad at any given time. As for brake fluid being a "lifetime" fluid. I would say as long as the fluid isnt brownish its ok to roll. Id seriously doubt the the previous owner had anything to do with your master cyls demise.
Offline Profile Quote Post Goto Top
 
Cobb
BANNED

My fluid was browm like ice tea. It maybe lifetime like oil, but it can get dirty, absorbe water and break down.
Offline Profile Quote Post Goto Top
 
rcdraco
New Member
[ *  * ]
Actually new info on this. It turns out I thought I was hitting the floor, the pedal is spongy at the top, then about half-way it turns very heavy, right about where it starts to grab respectfully.
Offline Profile Quote Post Goto Top
 
Jezza
Member Avatar
Boost Junkie

Still check out MC ... sounds fishy to me :ermm:
Offline Profile Quote Post Goto Top
 
rcdraco
New Member
[ *  * ]
Like I said, for the price of both, and the work involved, I'd be safer off changing both. I plan to bury this car, I like it too much to sell it.
Offline Profile Quote Post Goto Top
 
JoeBob
Member Avatar
Why you Mutt!

I've had this problem with other cars. Replace the master cylinder. (Back in the day, we used to get rebuild kits for the master cylinder and rebuild them, but that was before the Miracle of China.)
Offline Profile Quote Post Goto Top
 
work car
Member Avatar
obsessed!!

x10 on the master cyl this IS your problem! change it and be done.
Offline Profile Quote Post Goto Top
 
1 user reading this topic (1 Guest and 0 Anonymous)
« Previous Topic · Tires/Wheels/Bearings/Brakes · Next Topic »
Add Reply