Brake troubleshooting question...

[Metal Twister]

So I'm heading home last night and I notice the brake peddle is not holding pressure and is creeping slowly towards the floor with constant pressure on it. I can feel it slowly loosing pressure. It got to the point where I couldn't stay stopped at a light!

Got up this morning and inspected all 4 wheels, no moister anywhere so I bled the brakes with no sign of air in the lines. Did a test drive and I still have the problem. So its either the master cylinder or the brake booster. I noticed with the engine off that the peddle seems to stay up and not creep down. Im wondering if I can disconnect the booster and plug it off and drive it? If the peddle doesn't fade would that be a booster Issue? I can spring for a booster or a master cylinder but I don't want to buy both knowing I only need one of them.

Its my DD and need to get this figured out soon! Thanks guys for any help in advance.

 

[Avery4jc]

I have a friend with a truck that lost the booster and you could actually hear it hissing up under the dash when you put your foot on the brakes with the engine running. Not sure if they always do that but it would make sense. Do you hear anything? Sounded like rushing air.

 

[Metal Twister]

Well it has always made a sound when pressing my foot on the peddle but I wasn't listening for anything unusual this morning. I will check that out. Figured out that it is the typical symptoms of a bad Master cylinder. Thanks for the help

 

[rampage]

Have someone step on the brakes while you inspect the rubber lines for swelling, both the front wheels and the rear center drop lines.

 

[4X4HIGH]

The master cylinder is leaking within itself, I would buy a master/booster combo and install it and be done (usually very close to same cost as just the master or booster by itself).

 

[Metal Twister]

Oh Baby... Nothing quite like rolling down a SoCal hwy off ramp and half way down you discover you have no brakes at all! Holy ****! I started down shifting and using the e brake which only kinda slowed me down a bit. The 38" Swampers didn't want to stop... I had enough time to get a good grip on the air horn as I slid through the 4 way stop at the bottom of the hill. Sad thing is I knew better but I had to get my rig to my shop to fix it. I could care less about my rig but the thought of a regular sized car being eaten up by the Desert Hippo would not be a pretty sight. Anyway Napa is going to deliver a new master cylinder and it should be just fine now. Oh for you guys that don't know, I have a 74 Jeep Cherokee on a stretched K5 Blazer frame and running gear... Its a beast!

The Cherokee Desert Hippo in front of a stock Wagoneer...

 

[Metal Twister]

The master cylinder is leaking within itself, I would buy a master/booster combo and install it and be done (usually very close to same cost as just the master or booster by itself).

Thanks for the suggestion... I checked into them and I really only need a master cylinder. My cost is like $30.00 and the best price on the combo My cost is $150.00. Thanks again for the help and advice!

 

[Avery4jc]

I have to say that's incredibly careless and stupid to drive a rig with known brake issues down the road. If you wrecked and hurt someone then what? Don't be cheap, get it towed next time.

 

[Metal Twister]

Agree 100%... Very stupid on my part.