Brake bleeding lesson relearned

[MoorparkMark]

Greetings from Moorpark ,

I’m a wee bit anal about everything on my Jeep being in good working order and in some cases looking good, so I replaced the brake fluid reservoir with a new one. Looks great. Part of the project was to bleed the brakes to flush out the old fluid - easy peezy right?

Here’s the problem. I’ll give the answer below.

Loosened right rear bleeder and attached the Mityvac hose and pumped away. No fluid, zip, zilch, nada. Removed bleeder, no fluid. Yes, the reservoir cap was loose and there was plenty of fluid. My first thought WTF over? Then it dawned on me....

When parking The jeep in the garage I set the parking brake. When the parking brake is set it is a mechanical function expanding the brake shoes using a lever and has almost nothing to do with the hydraulics of the brake system. It does however do a great job of relieving all the pressure in the wheel cylinder. Enough so that with the rear of the vehicle jacked up no fluid escaped when I removed the bleeder. Out of respect for those who know better I gave myself a bop on the forehead and uttered a Homer Simpson doh!

 

[Boinked]

I think most of us have tried pulling off rear drums hitting them with a hammer screaming at the top of our lungs only to find out the parking brake is on.

 

[Thunderhead]

Sure enough I changed my pads last weekend, no problem on the fronts and as I was working on the rears our diesel mechanic walks by stops looks and says your e break is on! Walks on

 

[xackley]

Before I could drive my jeep out of a field where it sat for 3 years I had to replace all the metal lines.
When I filled the reservoir, I was surprised when I saw brake fluid leaking out of all the bleeders that I had opened before doing the lines. I closed the bleeders and the brakes worked fine. My wife was disappointed, missing out on the push and hold.

 

[Nimbley]

Before I could drive my jeep out of a field where it sat for 3 years I had to replace all the metal lines.
When I filled the reservoir, I was surprised when I saw brake fluid leaking out of all the bleeders that I had opened before doing the lines. I closed the bleeders and the brakes worked fine. My wife was disappointed, missing out on the push and hold.

Gravity bleeding works great if you have the time and patience. :thumbsup:

 

[MoorparkMark]

I saw tears in my wife’s eyes when I brought home the Mityvac. Turns out they were tears of joy .

 

[Mike_H]

I have a mityvac...and I normally want to throw it in the trash. It seems that I always get air leakage through the threads of the bleed nipple...which means I'm ALWAYS pulling air bubbles with it.

 

[MoorparkMark]

To air is human? The air is not causing any problems other than less vacuum being applied which ironically sucks cause it doesn’t suck as much. Have you tried opening the bleeder a bit less? I’ve seen recommendations to put a dab of grease around the fitting- not something I’m going to try.

 

[mrblaine]

I have a mityvac...and I normally want to throw it in the trash. It seems that I always get air leakage through the threads of the bleed nipple...which means I'm ALWAYS pulling air bubbles with it.

Get a helper with a clean finger. Pull the bleeder and have the helper apply the clean finger over the bleeder hole to stop the fluid from making a mess on the floor. Wrap a couple wraps of Teflon tape on the bleeder threads making sure to keep it above the bleed hole. Remove clean finger, install bleeder and that will slow down how much air goes in around the threads.

Or, dispense with clean finger and push the brake pedal down with a stick to the front of the seat and no worry about the master running low.

FYI, we've tried the vacuum bleeders, they don't suck as much as they should so we don't use them. They also don't tell you a lot of things that a manual bleed does.