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Show me your Live axle Brake Lines
Edwardo - 9/5/21 at 08:25 PM

As title - would appreciate anyone who has some pics of how the the brake lines run across your Escort live axle please.

I've got to do mine next week and am looking for a neat/tidy way of running them rather than the previous owner who just ran them across from side to side completely unsupported

Cheers
Tony


shindha - 9/5/21 at 08:48 PM

My best effort on a Westfield SE

rear axle
rear axle


Edwardo - 9/5/21 at 08:50 PM

Thanks Shinda

Keep em coming if you have them please?!


pigeondave - 10/5/21 at 09:25 AM

I'll try to get a pic later, as the car is at the garage and not part of home.

But my axle had a little tab in the centre of the diff just below (might have been above) the loop which supports the bush for the hand brake actuator. This little tab was bent around the brake line.

I have drums so its not a split, they are on a radial circuit. So one feeds the other. It's as shown in the escort mk2 Haynes manual


Edwardo - 10/5/21 at 09:54 AM

That would be great cheers!

That's how it was on mine originally too. From the flexi into the N/S brake cylinder (totally unsupported) - and then from the N/S cylinder all the way back across the axle to the O/S (again totally unsupported).

Wasn't sure whether to put it straight into a T after the flexi and just run out to each cylinder. Gotta be better for brake balance hasn't it than running to one and then across to another? I'm sure the pressure is probably the same tbh - just seems a bit counter-intuitive. Must be ok though if the Ford manual shows it as that.

I have a couple of the original metal tabs on the axle housing - but don't really want to use them to hold the line as I fear they will rub and fret with vibration.

Have heard some people use rubber fuel hose sections wrapped around the brake pipe and then cable tied to the axle.

Also heard someone saying they used big rubber lined (65mm'ish diameter) P clips around the axle and then clipped the lines to the fixing holes on those. This is something I'm looking into possibly.


myke pocock - 10/5/21 at 11:17 AM

Exactly what I did on mine Edwardo. Flexi to T junction then across to either side. There are convenient brackets on the axle (if they havent been taken off) to fit to. Easy to tack brackets on anyway if needed. Where my pipes used the existing tags on the axle I split a bit of rubber pipe and slipped it over the brake pipe to prevent it chaffing.


coyoteboy - 10/5/21 at 12:04 PM

I always thought you had to have a diagonal split, but checking the IVA docs you don't have to. No part of me would want to rely on rears only if I had a MC seal failure! Some nice routing there though, very neat.


JAG - 10/5/21 at 12:30 PM

"Front:Rear" split is the normal way of splitting the brake circuits on a rear wheel drive car. The front brakes are on one circuit and the rear brakes are on the other circuit.

"X" split is more usual on front wheel drive cars. One front wheel and the diagonally opposite rear wheel on the same circuit.

The main reason for the difference is the weight distribution (weight over each axle) and height of the centre of gravity of the car. The height of the centre of gravity governs the weight transfer during a braking event.

Basically, if you have a leak in one circuit, you have to engineer the car to ensure that you have 50% of the vehicles total brake output available on the remaining 'good' circuit.

Some cars can have a 60+% weight over the front wheels. If you had a front:rear split system on such a car, and the front axle circuit leaked, then you'd have about 40% weight, hence 40% of the total brake force available via the rear brakes. That would not meet the legal requirement for the brake system as laid out in ECE Regulation 13h which specifies the performance of the brake system on your car.

Hence the X-split which means you still have 50% of the vehicles total brake output available even if you have a 60+% weight distribution on the front axle.

Cars like the Locost are very low to the ground (low centre of gravity) and have 50/50 weight distribution. Hence they are perfectly designed for a front;rear split system. Even with drumbrakes on the rear axle you will have plenty of braking available if you have a leak on the front axle circuit.

[Edited on 10/5/21 by JAG]


coyoteboy - 10/5/21 at 01:24 PM

Fair points there, I'd not considered it in that much detail to be honest but that makes total sense. Although it doesn't explain why diagonal split ISNT usable - you'd still be able to have 50% of the brake force applicable.

I've often wondered about this too, as if I pop a bleed nipple on a two-circuit system, I'd expect to have half a circuit active, but I never do - they always go to the floor with zero resistance. Now you have me questioning everything about brake systems that I thought was received wisdom.

[Edited on 10/5/21 by coyoteboy]


JAG - 10/5/21 at 02:58 PM

You are right X-split would also work on a Locost.

The main reason I wouldn't do it is because of the torque steer you would experience if you did have a half-system failure. The front:rear split system will be easier to control if you have a problem

Your other question; the pedal will go to the floor once or twice (your pumping out the fluid from the failed circuit) but if you keep pumping then the 'good' circuit will eventually get pressure and you will get braking back

If it happens it's quite a shock but keep on pumping and all will be well


JAG - 10/5/21 at 03:01 PM

As to the OP's original question...

I have a braided flexible hose that attaches to a T-piece on top of the diff' in the middle of the Live Axle. Then hard pipes that run to each wheel. As a previous comment I used the metal tabs (welded on by Ford I guess) to retain the hard pipes to the axle case.


Edwardo - 10/5/21 at 03:09 PM

Thanks JAG - Interesting info about the tin top split braking systems too.

So your copper/kunifer lines are sitting directly in the metal clips ford put on the axel with no protection? Are you not worried about them fretting with vibration at all?

Cheers again all
Tony


JAG - 11/5/21 at 08:03 AM

quote:

So your copper/kunifer lines are sitting directly in the metal clips ford put on the axel with no protection? Are you not worried about them fretting with vibration at all?



I'm not worried about fretting because I used Steel pipes. If I was using Copper or Kunifer I would have done it differently.

People use Copper or Kunifer simply because it's easier to manipulate and fit to a fully built car. But Car manufacturers use Steel pipes for a good reason so while I was building the car it was easy enough to use Steel.


procomp - 13/5/21 at 12:51 PM

On the race cars we run a single flexi to the rear inside the tunnel to a T with brake switch so a 4way rather than a T as such.
Then flexi to each side.
I never use copper on any of the brake lines as to easy to damage. Flexi is not expensive, a whole car can be done for less than £100 as only 5 hoses required.