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Old 01-20-2011, 01:04 AM   #1
muckyp
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I need some brake help

Let me first say that this truck has been sitting for several years now. The master cylinder, brake lines, calipers and all brake components were new (well actually they were installed new by the PO, but had been sitting for several years). So the problem is I can't get the brakes bled. I bench bled the master cylinder and reinstalled it on the truck and attempted to begin bleeding at the right rear wheel with one of the mighty vac brake bleeders. I got nothing!
So I then began reading on here about brake problems. I read one about the lines being clogged so I disconnected the brake lines and blew air threw them to confirm that they were clear and they were.
Can anyone suggest where my problem might be? Does it sound like the proportioning valve is bad?
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Old 01-20-2011, 04:05 AM   #2
matthew20061
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Re: I need some brake help

Sounds like you have a good start with bench bleeding the master so that is checked off the list. First are you getting any fluid flow past the proportioning valve? Usually prop valves don't go bad, but the one on my truck ended up having issues. If you aren't getting fluid flow past it then try resetting the proportioning valve. If you are getting fluid flow all the way back to the rear brake wheel cylinders then the wheel cylinders are probably bad if you can't get them to bleed. At least that has been my experience, also if the system has been dry for a couple of years its definitely possible for those new parts to go bad.
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Old 01-20-2011, 06:13 AM   #3
cdowns
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Re: I need some brake help

theres a pin on proportioning valve that needs to b clamped in place to properly bleed brakes // should start at brake furthest away from master cyl which is the left rear brake
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Old 01-20-2011, 11:32 AM   #4
Wrenchbender Ret
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Re: I need some brake help

Pull the bleeder valve out & clean it good. Poke a wire in the hole in the wheel cyl. with the valve out. Sometimes they get blocked by crud.
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Old 01-20-2011, 07:41 PM   #5
muckyp
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Re: I need some brake help

I do not believe there is fluid past the prop valve as I took the line loose just below it and blew air through to the rear wheels. About the valve, is the pin the little green pin or the silver part that surrounds it?
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Old 01-21-2011, 10:49 PM   #6
muckyp
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Re: I need some brake help

So is it safe to assume that if I cannot get air through the rear port on the prop valve that there is something wrong with it?
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