Odd Brake Issue

Jeff,
The pressure pot I was using was putting almost a gallon through in under a minute. I had all 4 wheel bleeders open with plastic bottles and aquarium hose on them to catch the fluid. Almost everything in the system was new, so I was able to return the fluid to the pressure pot when I finished.

Don

 

Thanks Don,
I have heard "speed bleeders" can create more bubbles. Definitely not what I need.

I did not have time to look at this over the weekend, new dog! (eek) Hope to get some time tonight.

 

Not familiar with brake systems that have vacuum boosters, but you said this is a on going issue that you had to pump your brakes.

Is is the pushrod that attaches to master cylinder adjustable? I'm wondering if it's utilizing the whole bore of the master cylinder when you press the brakes. For example if it is adjustable, and adjusted too short it could only be pushing the piston half way even though the brake pedal goes to the floor. When it does this it makes it impossible to bleed the brakes correctly.

Could just be unrelated, or somethig helpful.

 

I replaced the booster, no difference. Must still have air in the lines or something. Back to square one!

 

Jeff, did you put a vacuum gauge on that source? need about 18 minimum to 21 to be correct............Did that new booster come with a new check valve? Residual valves in line somewhere? or built into the Master Cylinder or Proportioning valve?........What is the history on the Master?

 

Hi Tarry,
New M/C but have not checked vacuum yet.
Seems odd that it worked before.
I tried a new M/C and the first one back on with same results. In line residual pressure valve to front only. I may try to replace that, had one go bad before. Not sure why that would affect this. No proportioning valve. I think my friend has a pressure bleeder might try that.
Supposed to go to Mud in Yer Eye this coming weekend with our club as a volunteer/helper. Going to suck if I can't get this figured out!

 

Booster did come with new check valve. Vacuum off intake manifold.

 

Yep check your vacuum at the source........if it's under the carb or in the manifold.......sometimes it can get plugged up. I would also do a 10lb residual valve for the drums or see if your Master has them internal?............Lots of Masters if correct for the system are internal........and Proportioning valves can also be had that way...........call these folks tomorrow and talk to Sandy, she is the owners daughter he may even be there, but he was getting up in years..............these people are as well versed in Brake issues as anyone I have every ran across.........tell her your problems , she will want to know everything about your system so be prepared. Sharp Ladies.

Power Brake Sales
1517 McCormack Street
Sacramento, CA 95811
Toll Free800) 624-8185
Ph916) 446-7829
Fax916) 446-7569

If you have further questions or would like more information on these items please give us a call or drop us an e-mail. We would be pleased to send you more detailed information or provide you with a personalized quote.
Sandra Standley & Kathy Peter, Owners.

 

Thanks Tarry
Awesome info and I really appreciate the name and number.

 

So I just called the number Tarry gave me. Just as suspected still air in the lines. They gave me 2 ways to try and clear the air so hopefully sometime today I can get to it.
1. Get brake lines horizontal, manually bleed, engine off.
2. Pull calipers, block with a piece of wood. Raise calipers as high as possible and bleed manually!

According to the gentleman at Power Brake the orifices in the M/C are too small to move enough volume to get the air out of the lines. Speed bleeders will not work either.

Hopefully results later today.

Oh, vacuum was in the 20 range.

 

Here's another thought for you, Jeff. Rick was having the same issue you described at the beginning of your post. Brakes fine on road, having to pump them offroad, especially when heading uphill. He had his residual valve plumbed in backwards. Simple mistake, but it allowed the fluid to drain back when the nose was pointed up.

 

Thanks John,
I'll check that out.
I hope to get the brakes bled tonight but have to go to daughters softball game.

 

Residual pressure valve installed correctly.

Bled the way I was told and now have brakes. I also adjusted the M/C push rod out a little as the new booster seemed to have more pedal play than the old one. I guess the real test will be to see how it does off road. Hopefully I will get to still go Sat if my Dr. gives me the green light tomorrow.
Minor procedure tomorrow to have fluid drained from both knees.

 

Keep us posted on how well you stop

 

Thinking about taking it out for a putt right now.

Was supposed to spend the night at Hollister Hills for "Mud in Yer Eye" but my Doc recommended I don't. Probably going to make it a day trip tomorrow.

 

Brakes worked great all day yesterday! They were a little too tight and were dragging some. A quick trailside fix and I was able to shorten the booster rod adjuster about 2 turns. That fixed it and they worked great. I may take the adjuster back out and lengthen it 1/2 turn at a time.
As always thanks to this great forum for the help!

 

Good News Jeff..............Nice to get things back to normal.

 

I am glad it was a simple fix, time to have some fun!

 

Great news. have fun.