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Krieger
Last night I woke up thinking of a second redundant hydyraulic system for the rear brakes only. Perhaps a T-1 master, or some small slave cylinder attatched to a handle that could apply force for braking....Then I says to myself "self you could plumb this into the existing line going to the rear of the car and put a one way valve in that line to keep it pumping the rears only" Also a one way valve would be need to protect the e-brake pump from the main master cylinder. I know a cable is the ultimate redundant system, but this could be a cool compromise keeping complexity/weight/junk off those rear wheels. first.gif or : stromberg.gif

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Mark Henry
QUOTE(Krieger @ Sep 2 2010, 09:43 AM) *

Last night I woke up thinking of a second redundant hydyraulic system for the rear brakes only. Perhaps a T-1 master, or some small slave cylinder attatched to a handle that could apply force for braking....Then I says to myself "self you could plumb this into the existing line going to the rear of the car and put a one way valve in that line to keep it pumping the rears only" Also a one way valve would be need to protect the e-brake pump from the main master cylinder. I know a cable is the ultimate redundant system, but this could be a cool compromise keeping complexity/weight/junk off those rear wheels. first.gif or popcorn[1].gif


Not a legal E-brake, must be mechanical.
Eric_Shea
Hot brakes and fluid (what they are when you usually set it) always cool. This is why they insist upon the cable/mechanical set-ups.
76-914
Mark's right, but if you must.......... http://www.aircraftspruce.com/catalog/lgpa...gbrakevalve.php
Mike Bellis
I'm running one of these. the PO gutted the parking brake system.

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Krieger
Damn I thought I came up with a new Flux Capacitor, but this looks easy. How much was it. But again not street legal set up according to mark. but the only thing I would want this for is for a true emergency brake, not a "parking brake"
jmill
If you want a true E brake then the last thing you want to do is plumb it into the existing line. A ruptured line = no brakes. Mechanical is the only way to go if you want to stop in an emergency. I've had all kinds of failures from ruptured lines, failed master cylinders, leaking pistons and pads ripping out of the calipers. Without a mechanical back-up I wouldn't be here typing this.
davep
Federal law requires a functional, and mechanical, emergency brake.
The parking brake is a secondary and lesser function of the emergency brake.
Street or track, everyone else has a right to expect that your emergency brake will function in the event of a hydraulic failure.
McMark
Don't some people use a 'line lock' to keep pressure on the rear brakes. With that you park your car, step hard on the brakes close the 'line lock' valve, and then it maintains pressure in the rear calipers.

That being said, I'm a STRONG believer in the mechanical EMERGENCY brake. It's not a parking brake. It's for that 1% chance where you say, "OH SHIT!" and that little level saves your life or your car.
SirAndy
QUOTE(McMark @ Sep 2 2010, 12:10 PM) *
Don't some people use a 'line lock' to keep pressure on the rear brakes. With that you park your car, step hard on the brakes close the 'line lock' valve, and then it maintains pressure in the rear calipers.

You still have the problem of losing pressure when the brake fluid cools ...

shades.gif Andy
Sleepin
Is a wood block mechanical enough? laugh.gif
McMark
NEVER use a wood block. The appropriate tool is a brick. tongue.gif
Sleepin
That also doubles as an "Emergency Entrance Device"! biggrin.gif
914four
QUOTE

Not a legal E-brake, must be mechanical.



Can the mechanical brake be on the front?
messix
QUOTE(McMark @ Sep 2 2010, 12:10 PM) *

Don't some people use a 'line lock' to keep pressure on the rear brakes. With that you park your car, step hard on the brakes close the 'line lock' valve, and then it maintains pressure in the rear calipers.

That being said, I'm a STRONG believer in the mechanical EMERGENCY brake. It's not a parking brake. It's for that 1% chance where you say, "OH SHIT!" and that little level saves your life or your car.

"line lock" is used by drag racers to lock the front wheels to do a burn out with out crossing the starting line.

line lock is not a emergency brake, it's a valve that closes to "lock" the pressure to the brake circuit that it is installed on.

i would not trust the primary hydraulic system as an emergency brake. and to do a simple mechanical disc brake set up to the half shaft at the tranny would be so simple.
sixnotfour
I am suprised Troy didnt mention this setup , old school fourwheelers used this for hill holding and winching,
supplementary brake lock must be reapplied every hour has low pressure warning,
other models have a pump to maintian pressure
http://www.mico.com/store/brake_locks



messix
QUOTE(sixnotfour @ Sep 2 2010, 10:42 PM) *

I am suprised Troy didnt mention this setup , old school fourwheelers used this for hill holding and winching,
supplementary brake lock must be reapplied every hour has low pressure warning,
other models have a pump to maintian pressure
http://www.mico.com/store/brake_locks

we used those on our bucket trucks.... but now they are not used and are not osha approved.

standard e-brake and chock the wheels is the only osha approved method.

micro locks used to be used off road but have fell out of use because of some accidents where people depended on the micro lock and were winching from out side the vehicle. the vehicle moved with no driver to correct or prevent the movement, bad things happened.... not used any more.

micro locks are not an emergency brake nor are they a parking brake!

seals leak, fluid cools, pressure subsides = bad things
MoveQik
QUOTE(McMark @ Sep 2 2010, 12:55 PM) *

NEVER use a wood block. The appropriate tool is a brick. tongue.gif

Both are great but very tricky to hang out the window at 50+mph and place it *just right* At that point I would only recommend using when you have a co-pilot available. I mean....let's be safe out there.
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