will not bleed

[OLDSKOOL]

i can not get any brake fluid to the rear wheel cly replaced the mc with another rebuilt still no rear pressure bench bleed the mc seemed ok, any ideas im running 67 mustang mc 40 ford frounts 61 ford pu rears with a adj rear proporting vlave the rear bowel of the mc goes to the frount brakes any ideas tks rick also i temp removed the proporting still no luck tks

 

[putz]

Let me get this straight fluid comes out of master but thats it.was it getting to the proportioning valve? Have you tried someone pushing pedal down with bleeder open then close it when they hit bottom with the pedal. then let up pedal then repeat sometimes this works better than pumping it up and cracking the bleeder under pressure. till you get fluid then pump them up like normal.Good luck

 

[OLDSKOOL]

this time i removed the mc bench bleed it, 3out o f 6 strocks i had pressure out the frount port, but allways had pressure at the rear, i guess the mc must be bad but this is the second one that acked like that , i guess a rebuilt mc deliverd to your door for 37.00 wasnot that deel i thought, just ordered a new one, no more wight box parts tks rick

 

[estesken]

We teach several different ways to bleed brakes. One method is similar to what Putz described only I have them take the bleeder clear out and put there finger over the hole. your finger will work as a one way check valve then, have the wheel guy take long steady strokes up and down. This will move a large volume fluid. Keep eye on reservoir. Finish bleeding oldschool. This method does make a mess, so watch out for your paint squirting or yourself in the face.

One way of trying to verify master cylinder operation is to just plug the ports at the cylinder. This can be done on car with the correct plugs or old lines pinch short and brazed. With a good and bleed cylinder, pedal will be rock hard. piston in the cylinder will only move slightly. I suppose it would possible to miss diagnose if the cylinders were pitted at the middle travel.

Hope this help someone.

 

[LumenAl]

Fat Pat the brake guru on NTBA site consistently states... never buy rebuilt MC's...

 

[Wild Mango]

Amen Brother LumenAl.
And I would add, NEVER buy rebuilt wheel cylinders and calipers as well. Buy new ones from a reputable manufacturer.
The minute you see these things start leaking is evidence they are going to try to kill you.
On a tandem master cylinder I find its better to use a pressure bleeder like the ones you can make using a $10:00 garden spray. That way you can start at the farthest wheel cylinder and work your way back a couple of times and also get a good dose of fluid through to flush the system.
Used brake fluid goes into the waste oil recycle drum where it belongs.

 

[jbisme]

I can't agree more, never use a rebuilt brake part. Call me crazy, but I like to know the pistons in a master or brake cylinder move nice, smooth and tight.

Rebuilt alternators are one thing, but new brakes saves lives.

 

[Duke]

Go Parts - I might use used but good parts.

Stop Parts - I use new and best I can find.

My theory is that going is optional, But stopping is mandatory and will save your life or a family member.

 

[blownt]

Ever since I built the bucket I had NEVER had decent brakes. It would stop but you could never get them to lock up (I know you don't want them to, but I could slam on the pedal and it would just stop normally). And whenever I would work on them it was ONE MAJOR pain to bleed the system usually taking 4+ hours and mucho cussin. Any way one day the brakes were getting worse and worse going to a show. By the time I got there I had NO BRAKES.

Got back home and I said this is it. I am going completely thru the system. I had 1/4" SS lines with all AN fittings. Got rid of that and went with 3/16" brake tubing and brass fittings. Installed a Vega mc, bench bled it (with the rubber hoses back into the reservoirs) and bled the system and NO BRAKES. I could push on the brake pedal and nothing - to the floor. Put on another Vega mc I had in the garage off ebay. Same, no brakes. Went and bought a BRAND NEW Vega mc. No Brakes. Now I was getting PISSED. Bought a brand new 68 Mustang mc and THIS TIME I read the friggin instructions.

It said in fine print that on some models of master cylinders you must wait 10-15 seconds between pumps while bench bleeding the mc.

So I tried it. I plugged the mc ports with a 3/8" and 1/2" fine thread bolt (3/8-24 and 1/2-20 which is what the mc ports are). Filled the reservoirs and gave it ONE pump. Waited about 15 seconds then one more pump. 15 seconds then another pump. After several more pumps WOW I am actually getting a hard pedal. I took out one bolt and installed the front brake line. Then took out the other bolt and installed the rear brake line. Then I started to bleed the system. Now before, this was a major hassle and took SEVERAL hours. But to my amazement after doing the prescribed bench bleeding method, I bled the entire system and had a NICE FIRM pedal in about 10 minutes.

I can only account this miracleous recovery to that special bench bleeding procedure that I had never done before. I don't know but it worked for me.

 

[EX JUNK]

There is an old saying that says: "After all else fails, read the instructions." A lot of guys believe that they will be considered less macho if they do but in the long run, who cares, if that is what it takes to get the job done right.

Jim

 

[Todd]

Wait a second, You can't get any brake fluid to the rear end of the car? You think the Master is bad but have an adjustable proportioning valve? Is the Pop valve completely closed?

 

[OLDSKOOL]

Thanks for your help. I have installed the new MC, at least it was asembelled in North America and it is now working fine.

Thanks,

Rick

 

[Fourdy]

I just went through this process and was stunned at how easy it was. I have never had good luck bleeding brakes before and it was always a struggle.

After installing all the lines (Drum/disk) I had a bit of tubing left so I made two loops that dumped back into the m/cyl about a 1/4" above the bottom. I always had trouble keeping the rubber tubes in the m/cyl while bleeding it.

I pumped the pedal until there was absolutely no air bubbles then hooked the lines back up. I then went to the furthest front brake and put a clear tube on the bleeder then into a quart jar half full of brake fluid. I could then pump the pedal, keep a watch on the fluid level and watch the tube until there was nothing but fluid in the tube. I could see the air in the jar. Letting the pedal up only drew liquid and no new air. Shut the bleeder and go to the next wheel.

It took less than an hour and with no helpers.

Fourdy