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-   -   100% New brake system ARGH (https://67-72chevytrucks.com/vboard/showthread.php?t=669281)

elf w/capital T 05-02-2015 04:20 PM

100% New brake system ARGH
 
I installed all new components. Brand new lines, calipers up front new wheel cylinders in the rear, added power booster, new prop valve, I cannot locate any of my paper work that ca me with the booster and valve BUT already bench bled master..

.I see a tool for the prop valve...

Not sure what I'm missing by not having the tool...

But I am not getting fluid to the lines or brakes.... I've only bled the brakes with the cover off to witness any fluid leaving the master cylinder about ten times...

I am aware the lines throughout the Truck are all empty but even disconnected lines from truck to prop valve...still nothing....




I guess my main question is....


How do I bleed my prop valve??

bbcmudtruck 05-02-2015 04:29 PM

Re: 100% New brake system ARGH
 
Try backing off one of the bleeder valves on one of your wheels and let it sit for a while with a cup to catch any fluid. Check on it every hour or so and see if that works. I've fought brakes for hours and a friend of mine suggested trying this. I left my bleeders open over night and finally got fluid to the wheels. After that, I ended up buying a vacuum brake bleeder from O'Reill'ys. I'd never mess with bleeding brakes again without one. You can bleed the brakes by yourself and catch all of the fluid at the same time. My buddies always hit me up when they need brakes bled after seeing how good it works. I think it was around $40 bucks or so a few years back.

GASoline71 05-02-2015 05:04 PM

Re: 100% New brake system ARGH
 
I was going to suggest the exact same thing. Gravity bleed them. Just don't let the master cylinder run dry.

I too invested in a vacuum bleeder system. EZPZ and worth the money.

Gary

treveiger 05-02-2015 07:38 PM

Re: 100% New brake system ARGH
 
I did the same thing with our truck. I gravity bleed them first then do the old school method. Have not bought a vacuum bleeder because I'm young and stupid still:lol: and I enjoy bleeding brakes.

elf w/capital T 05-03-2015 08:30 AM

Re: 100% New brake system ARGH
 
Okay thanks! I tried it last night and had nothing. Whats the Prop valve bleeder tool really for and how does one bleed the system with it?

67swb72klb 05-03-2015 08:53 AM

Re: 100% New brake system ARGH
 
Quote:

Originally Posted by elf w/capital T (Post 7157626)
Whats the Prop valve bleeder tool really for and how does one bleed the system with it?

It just holds the button in

Steve Cole 05-03-2015 09:15 AM

Re: 100% New brake system ARGH
 
Do a search for "resetting a pro portioning valve", lots of threads on that. Also look here: http://www.classicperform.com/TechBo...t.htm#testprop

MagmaJct 05-03-2015 02:00 PM

Re: 100% New brake system ARGH
 
Try backing off or disconnecting the brake pedal push rod. It's possible it's pushing the pistons forward enough to cause the pistons to cover the reservoir ports. Good Luck!

Regards,
Mike

treveiger 05-03-2015 04:49 PM

Re: 100% New brake system ARGH
 
You can use a c clamp to push the valve in. I found a 3 way clamp at my local hardware store and works great.

elf w/capital T 05-03-2015 06:42 PM

Re: 100% New brake system ARGH
 
What if when I remove switch on the prop valve...I see nothing moving...maybe it's not pushing it enough? Thanks everyone... this whole thing has been a nightmare and seems like I cannot win. I'll keep everyone updated with progress.

treveiger 05-04-2015 02:11 AM

Re: 100% New brake system ARGH
 
The switch should just push in until you hear a click noise. I don't know if you can just remove the switch. How long is the push rod for the pedal to the booster? Did you use it off your old mc? The powerbrakes and the manual brakes had different rods. I think the manual brakes had longer rods and a deeper bore in the back of the mc to keep the rod from falling out. The longer rod would press on your new booster/mc keeping it from properly bleeding.

elf w/capital T 05-04-2015 09:31 AM

Re: 100% New brake system ARGH
 
Yeah I'm thinking the master cylinder I have now needs the little booster adapter. My aluminum cpp one leaked so I got an original one but I didn't use the adapter because it was rock hard...

Now I'm thinking I need the longer rod piece because I took the switch out of the prop valve and see no moving parts in the prop valve hole for the plunger. booster makes a slight hiss so that is good ha

treveiger 05-05-2015 02:18 AM

Re: 100% New brake system ARGH
 
Maybe some pictures will help if you didn't figure it out yet. So did you add a booster to a manual mc?

cblock 05-05-2015 03:05 AM

Re: 100% New brake system ARGH
 
I have a71 c10 that sat for many years and the rear brakes where stuck, after turning fhe drums, installing new shoes and rebuildijg the cilinders I getno pressure to the rear. I have pressure at the master cyl but not after the proportion valve. so I'm very interested in whats your outcome.thanks

68C15 05-05-2015 06:17 AM

Re: 100% New brake system ARGH
 
try back bleeding with a syringe and some vacuum hose

treveiger 05-06-2015 01:59 AM

Re: 100% New brake system ARGH
 
Cblock you could also try gravity bleeding the system. Did you make sure your safety switch isn't engaged on the proportioning valve?

mahanian 05-06-2015 02:07 AM

Re: 100% New brake system ARGH
 
If you bled it without the proportioning valve tool then you've functioned the safety feature in the proportioning valve that prevents the brake system from having a complete failure due to a leak. You have to reset the piston inside the proportioning valve back to the center and use the tool to hold it in the center while you bleed the brakes.

mahanian 05-06-2015 02:10 AM

Re: 100% New brake system ARGH
 
Or if you aren't getting fluid from the master to the proportioning valve then you didn't get all the air out of the master cylinder when you bench bled it

superfly66 08-17-2015 10:05 PM

Re: 100% New brake system ARGH
 
So...What was the end result or solution!??

elf w/capital T 08-19-2015 11:41 AM

Re: 100% New brake system ARGH
 
Sorry guys, well after all the gravity bleeding and vacuuming, the mastercyl was internally bad, eneded up getting new one, gravity bled and had my girl pump the pedal. I also thing it had the wrong spacer piece where to push rod hits in the mc. Think it was too long.

Taibo 08-20-2015 06:37 PM

Re: 100% New brake system ARGH
 
Quote:

Originally Posted by elf w/capital T (Post 7278538)
Sorry guys, well after all the gravity bleeding and vacuuming, the mastercyl was internally bad, eneded up getting new one, gravity bled and had my girl pump the pedal. I also thing it had the wrong spacer piece where to push rod hits in the mc. Think it was too long.

Life IS, after all, a learning experience. Old guys have an advantage in life; they have already run out of mistakes and dumb ideas.:bite:


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