Why doesn't my right ebrake work?, It's the asymmetric cables, dummy. Options

[davesprinkle]

Here's why most modern cars have the ebrake handle in the middle of the car -- it's so the cables running to the wheels have identical length and path. How do I know? Here's the anecdote:
For the last year, I've been struggling with my ebrake system. The right caliper just wouldn't clamp as tightly as the left. I've got rebuilt calipers, new pads, new cables, proper clearance, but no worky.

Finally found out why. It's the internal drag of the actuation cables. The passenger-side cable is substantially longer than the driver side. Also, the right-side cable has 3 right-angle bends vs the left-side cable with none. This results in so much internal friction that the cable just binds solid when it's pulled.

I was able to improve the situation somewhat by lubricating the cable. Still not perfect, but much better.

[jim_hoyland]

I have the same issue.....where did you lube the cable ?

I heard, years ago, of a 914 using a pair of mini hydraulic actuators to pull the E-brakes. I believe they were mounted on the fire wall with a straight line shot to the calipers. Any thoughts on this ?

[davesprinkle]

I have the same issue.....where did you lube the cable ?

I heard, years ago, of a 914 using a pair of mini hydraulic actuators to pull the E-brakes. I believe they were mounted on the fire wall with a straight line shot to the calipers. Any thoughts on this ?

Yeah, hydraulics would definitely solve the cable friction issue. Cons of such a setup:
1. extensive engineering and fab effort
2. another hydraulic system to service
3. some might be philosophically opposed to abandoning a mechanical backup

It's tough to do a good job lubricating the cable. I used two approaches:
1. First, I used some lightweight mineral oil (bicycle chain lube) and allowed it to wick down the cable. (Working at the interior end of the cable.) The oil was thin enough that capillary action pulled it down the cable.
2. Next, I wiped some grease on the inner cable and worked the cable back and forth.

I noted that most of the cable's friction is due to the first 90 degree bend, the one immediately at the firewall. Conveniently, this is the area most easily lubricated.