Leaking master cylinder

[uvachief]

Yeah but Rasta is crazy.....

[uvachief]

Okay. I have been assuming the state inspection mechanic wasn't crazy or lying when he said the brake MC was leaking. Car has been sitting for about a week. Pulled it into the garage last night to work on the brake master cylinder. Call me crazy but look at the pictures below. I don't see any evidence of a leak.

[uvachief]

Also, um..errr....the connector is frayed on the connector to the brake MC resevoir. There are two leads to the cap. One of them basically came apart when I disconnected it. Is there a quick fix or do I just need to splice in a new one? I am getting the lovely "!" with the brake fluid light on the dash now intermittently. Worried I am not getting fluid the brakes with this "dis-connection" on the far left lead. Parked it until I hear back from the gurus.

[John_AZ]

Doug,

The brake MC will leak between the body of the brake MC and the brake booster.
You will see a tiny wet trail of brake fluid under the brake MC to the bottom of the brake booster.

Get a flashlight to check.

It is also possible to leak inside the car. Pull the brake MC rubber boot forward that is by the firewall connecting to the brake pedal.

Try to repair the wire connection or get a used cap if necessary.

Cross your fingers when you pull up the reservoir. Use gentle force with a screwdriver placed between the reservoir grommet and the Girling brake MC--motion like a tiny "pry bar".

You may be lucky and both the MC grommet and reservoir will lift UP in one piece.

Gently try both methods.

GL
J_AZ

[uvachief]

You see had happened was....checked the footwell. No evidence of leak near the brake pedal where the rubber boot is against the fire wall. I did notice slight wetness but could be grease also where the steering column goes into the firewall. Went back to the reservoir cap. When I disconnected the leads, one of the male tabs from the cap came with the lead and out of the reservoir cap. I think all I need is one of these. I tried fiddling with it and re-attaching but the signal is not getting to the dash to tell it I have brake fluid in the reservoir. I did notice the brake fluid reservoir is at max fill line. I used a flash light to go all around the master cylinder where it meets the booster. I cannot find any evidence of a leak any where.

Here is my big question. Will the brakes get fluid if this reservoir cap lead is broken? I assume they will it just thinks the reservoir is empty. However, if the brakes are electronically controlled, i don't want to be driving and find out my brakes have locked due to lack of brake fluid. In other words, can I drive it until I can swap out the reservoir cap with new leads. Should I keep it in the garage until I can get the cap. The braking system is purely hydraulic isn't it? The sensor is just there to let you know if your fluid level is low I hope.

[John_AZ]

Originally Posted by uvachief

Should I keep it in the garage until I can get the cap.

The braking system is purely hydraulic isn't it?

The sensor is just there to let you know if your fluid level is low I hope.

When you had the state inspection, the inspector showed you where the leak was. (?)

The brake system is hydraulic.
The cap controls the dash light.

J_AZ

[uvachief]

No he didn't. It was a side comment that I should check it. I will give him a call.

[uvachief]

Okay, I called and he said it appeared to have been weeping around the BMC itself. I have checked and double checked. Nothing. I replaced the brake resevoir cap and the lights are all gone. Think this mechanic was just fishing for work. It has been parked in the garage over a white concrete floor all week and not a drop of oil or brake fluid anywhere to be seen.

[rhett]

[QUOTE=uvachief;7370606]Okay, I called and he said it appeared to have been weeping around the BMC itself. I have checked and double checked. Nothing. I replaced the brake resevoir cap and the lights are all gone. Think this mechanic was just fishing for work. It has been parked in the garage over a white concrete floor all week and not a drop of oil or brake fluid anywhere to be seen. QUOTE]

He said it appeared to have been weeping - and that is evident by the lack of paint on the lower front face of the vacuum reservoir. However, given that the car is 20+ years old, a bit of paint loss is to be expected as any dribbles of hydraulic fluid left on paint will take it off over time. As long as there isnt any wetness, I think you're OK.

It all looks hunky dory..

[John_AZ]

The picture rhett refers to does look OK. A MAJOR previous MC leak ---not just a single path or two of brake fluid eating the paint on the booster.

In the previous picture there does appear to be a slight "damp" look to the bottom of the brake MC at the booster. If you take a rag and wipe this area, does it look dry or oil/greasy?



J_AZ

[VirginiaF1]

Originally Posted by John_AZ

The picture rhett refers to does look OK. A MAJOR previous MC leak ---not just a single path or two of brake fluid eating the paint on the booster.

In the previous picture there does appear to be a slight "damp" look to the bottom of the brake MC at the booster. If you take a rag and wipe this area, does it look dry or oil/greasy?



J_AZ

If that stain does prove wet, is that enough pressure loss to affect braking performance in a panic stop?

[John_AZ]

It means the final -end seals are bad and the MC should be replaced.
See red pencil

.

OEM Girling MC rebuild kit circa 1996. Cost $99.



Impossible to answer the "panic stop" question

J_AZ

[uvachief]

Shoot. Everyone was correct. I did rub a rag and it is a little damp. It is quite dark and it doesn't necessarily smell like brake fluid but I think it may have an early stage leak.

[uvachief]

http://forums.pelicanparts.com/uploads22/2013+04+02_23+12+10_2051365191335.jpg[/img]

By the way, I did see this bit of moisture in the inside footwell near the steering column. Is that possible brake fluid or power steering fluid?

[uvachief]

[QUOTE=uvachief;7370606]

Is this moisture near the steering column in the footwell, leaking brake fluid or power steering fluid? I can rub it with a white rag and get some debris but it isn't wet. Could be old.

[Lapponia]

I would question myself why the brake oil container is only half full in picture.

[uvachief]

I see the minimum level marker and the fluid is above that level by a good inch or inch and a half above that marker. I don't see a maximum fill marker in the picture. I'll pop the hood and double check though. I haven't had to add any brake fluid since acquiring the car in 2010. I know the brake fluid light on the dash works as well as I broke the reservoir cap checkin the level the other week and had to replace it. As soon as I lift the cap out, the light comes on.

[John_AZ]

Check the opposite side for mark:



J_AZ

[uvachief]

Shoot. It is leaking from somewhere then. I've never added fluid but it is low. I have DOT 4 original ATE brake fluid here at the office (don't ask). TYP 200. Will that work?

[Gawernator]

ATE fluid rocks