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Discussion Starter · #1 ·
My newly purchased 27T goes good/won't stop. Car was built about 12 yrs. ago and everything seems to be top notch. Manual disc/drum setup with mc under floorboard. 2psi & 10psi residual pressure valves and Wilwood adjustable
proportioning valve. Stainless brake lines at all 4 corners. I have a soft pedal but it doesn't bleed down. I have bled the brakes twice using a vacuum pump at each corner but I am not able to move much fluid through the system that way and the air never quits coming (probably bypassing around the fittings). I get braking action with little pedal movement but even if I stand on the brakes it won't slide the tires. It sure feels like air in the system. The master cylinder has a double reservoir (front/rear). An earlier poster said one of the front wheel bleed ports should be open when bleeding the rears and vice versa. I haven't heard that before and have never done it on any other car but would that affect the bleed process?

Thanks
Bud
 

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A common mistake on these systems is using a master cylinder with too large bore, Like 1". These light cars can use a 3/4" master and feels like power brakes. My bucket has VW front calipers and I went down to a 5/8" master. Now it's a great stopper..:thumbup:
 

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Have you tried adjusting the proportioning valve? You want to turn it all the way in and count how many turns. Then bring it out half of that. That should be a good starting point. You want the front to grab before the rear, so keep adjusting til you get there.
 

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Discussion Starter · #4 ·
Thanks for the ideas guys but I don't see how either situation would account for the soft pedal. The proportioning valve is adjusted to about mid-travel and the front brakes are coming in first, maybe too much so. I adjusted the pushrod to the point the front brakes were dragging enough to heat up and stop the car (expanding air in the system?).
 

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A vacuum pump will only suck fluid (and air) through the system (and poorly at that). The system is designed to have fluid pushed though at positive pressure, not sucked at negative pressure.

Use the vac to get 90% there, then bleed the traditional way.... with your wife's foot on the pedal.
 

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I think you have air in the system. Bleed it the old fashioned way a few times and I bet it gets better. You also could start over and remove and bench bleed the master then reinstall the master and bleed system. You may have too much/not enough travel at the pedal. Is the push rod adjustable?
 

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make sure the bleeder is at the absolute top of the cylinder. Some of the brackets for the front brakes position the bleeder in a non optimal position
 
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