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Old 08-20-2018, 04:40 PM   #1
stuartuk
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6400 Brake problem

Hi All, I have a 6400 (1947) I have replaced for new all wheel cyls, and the master cyl and brake pipes, had the hydro off and still cannot work out why the system is loosing pressure, can anyone help with any peculiarities for the big trucks. thank you.
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Old 08-28-2018, 10:21 PM   #2
mr48chev
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Re: 6400 Brake problem

I suggest making a pressure bleeder to bleed the brakes with. One of the very few rigs I ever had serious problems getting the brakes bled on was one similar to that.

I don't know what they call them in the UK but a pressure bleeder can be made out of a 1 gallon weed sprayer from the hardware store. This link has some real simple instructions on how to make one that has little or no frills. You do need a proper cap that will fit your master cylinder or figure out how to make a cap you can clamp on top of it.
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Old 03-01-2020, 06:31 PM   #3
OlySezHey
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Re: 6400 Brake problem

What link Mr48? Thanx
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Old 03-11-2020, 10:49 AM   #4
VWNate1
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Post Brake Bleeding

I too am a big proponent of pressure bleeding brakes and hydraulic clutches...

The main thing is to not use too much pressure .

An oldie only need 3 ~ 5 PSI ~ more than that and you're risking a brake fluid bath .

? Where is the system loosing pressure ? .

Brake pedal sinks to floor upon application or leaks or what ? .

If you can afford it a Motion Pro (I *think*) is good and only $50 new, cheaper at the pawn shop or on craigslist...
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