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Before installing the MC I bench bled it on my vice until bubbles were not coming out. After connecting it to the proportioning value I had my fiance press the brake pedal a thousand times with the passenger rear bleeder screw loosened. Fluid was not flowing and the reservoir was not going down.
I went a step further and bought a vacuum bleeder that hooks up to an air compressor. Still no fluid was drawn out. Has anyone experienced this before? I might figure out a way to inject the fluid into the system from the bleed valve at this rate before I pull all my hair out.
I recently installed a new front disc brake and booster kit, new master cylinder and installed all new brake lines including the flexible hose connections to the front calipers and rear diff.
I couldn’t get fluid to the rear drums at all! I traced the brake line back and loosened fittings getting fluid until I got to the diff flexible hose. Turns out the new hose (can’t remember vendor, either LMC, Macs or DC) was faulty. Looks like the hose end was crimped on incorrectly and crushed the end tube. There was no visible damage from the outside.
neither blowing through the hose or using a compressor proved effective, luckily I had a spare so I installed it and got fluid to the rear right away.
might be totally unrelated to your issue but worth mentioning!
Before installing the MC I bench bled it on my vice until bubbles were not coming out. After connecting it to the proportioning value I had my fiance press the brake pedal a thousand times with the passenger rear bleeder screw loosened. Fluid was not flowing and the reservoir was not going down.
I went a step further and bought a vacuum bleeder that hooks up to an air compressor. Still no fluid was drawn out. Has anyone experienced this before? I might figure out a way to inject the fluid into the system from the bleed valve at this rate before I pull all my hair out.
Any help is appreciated. Thank you
I feel your pain. Going through similar issue on my f350 after replacing hoses and hard line to hydrovac. Going to buy a vacuum bleeder. With the virus I at least have more hair to pull.
Disconnect the line at the back side of the proportioning valve (the line that goes to the rear brakes) and see if fluid comes out when you try and bleed it....If so, check that rear brake hose they do swell shut with age... If thats not the issue then you know the problem is the proportioning valve itself as long as your sure you are getting fluid to it... Some proportioning valves need to be reset..they have like a pin you need to push... https://itstillruns.com/reset-brake-...-12018109.html
or call Pirate Jack and tell them your problem... All the power assisted vacuum pumps in the world wont pump through a collapsed rubber line or a unset valve...
A buddy of mine just had a similar problem on his 65 mustang... His rear brakes would lock up after driving a bit to the point he was stranded a few times... The rear hose was swollen on the inside, allowing enough brake pedal force to push the fluid through the hose, but the rear brake springs weren't strong enough to push it back after you took the foot of the brake... A new hose fixed him right up.
I feel your pain. Going through similar issue on my f350 after replacing hoses and hard line to hydrovac. Going to buy a vacuum bleeder. With the virus I at least have more hair to pull.
So annoying man! I just bought a 90 dollar vacuum bleeder hoping this would pull the fluid but no luck arggg.
Originally Posted by grapp
Disconnect the line at the back side of the proportioning valve (the line that goes to the rear brakes) and see if fluid comes out when you try and bleed it....If so, check that rear brake hose they do swell shut with age... If thats not the issue then you know the problem is the proportioning valve itself as long as your sure you are getting fluid to it... Some proportioning valves need to be reset..they have like a pin you need to push... https://itstillruns.com/reset-brake-...-12018109.html
or call Pirate Jack and tell them your problem... All the power assisted vacuum pumps in the world wont pump through a collapsed rubber line or a unset valve...
A buddy of mine just had a similar problem on his 65 mustang... His rear brakes would lock up after driving a bit to the point he was stranded a few times... The rear hose was swollen on the inside, allowing enough brake pedal force to push the fluid through the hose, but the rear brake springs weren't strong enough to push it back after you took the foot of the brake... A new hose fixed him right up.
Interesting I will have to see if theres a prop valve in the rear brakes. Im pretty sure theres just one line that goes to the rear and Tees off though. Do you suggest pressing the brake pedal in and then cracking that fitting that leads to the rear line?
Ill give your feedback a try this weekend and report back.
That link I posted is for a rear brake proportional valve, and your truck wont have one, however, the main proportional valve may have a reset pin as well, sometimes its under a rubber boot to keep dirt out.... I would take the rear rubber line lose at back and see if your getting fluid, then if not, remove the metal line at the front of the rubber hose to see if you have fluid coming out. its usually the brake hose swollen shut, if that doesnt do it see if the proportional valve has that pin. take a look at the pic, that rubber plug, there is a pin under it.. push on it with the rubber still on..
That link I posted is for a rear brake proportional valve, and your truck wont have one, however, the main proportional valve may have a reset pin as well, sometimes its under a rubber boot to keep dirt out.... I would take the rear rubber line lose at back and see if your getting fluid, then if not, remove the metal line at the front of the rubber hose to see if you have fluid coming out. its usually the brake hose swollen shut, if that doesnt do it see if the proportional valve has that pin. take a look at the pic, that rubber plug, there is a pin under it.. push on it with the rubber still on..
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Thanks for the pic. Unfortunately theres no rubber boot of any sort just the pressure switch looking thing on the top surface of the prop valve.
I downloaded the manual for my master cylinder from pirate jack. I realized the kit included an extension adapter that I didnt install (picture attached below). So I threw that on. I had my neighbor pump the brakes and as I cracked the inlet fittings to the prop valve noticed it bubbling air and fluid out. I also removed the outlet fitting and had him press down and hold and it was shooting fluid out strong so thats good. It got dark so we had to stop for the day. Ill keep pumping tomorrow to see if i can get fluid to rears at this point and try the vacuum bleeder again to see if I can get fluid to pull.
Another thing I noticed was this white plug tool that was included. According to this video I found it is essential to the bleeding process as stated @ 2:58. I will try bleeding the brakes again with this thing plugged in see what happens.
So I finally got the brakes to bleed today. I did two things but ultimately I believe it was the white tool I posted above that did the trick.
1) I re-tightened the brake fittings but instead of just apply constant torque I would tighten and untighten a 1/4 turn and retighten, repeating that process for a bit. I noticed it would keep going a little bit further each time forming/seating the the flare.
2) After that I removed the switch in the prop valve and replaced it with the white bleed tool mentioned above. I noticed the pedal starting to firm up. I began bleeding each wheel as normal until pedal was firm.
Thank you for the feedback and I hope this helps someone in the future.
