Mondeo brakes

The message from "Dag Stenberg" contains these words:

Weak rear drums are common to almost all modern cars. With the forward weight distribution, it's usual for the rear brakes to do sod all most of the time.

On what evidence are you basing your comments? Are you saying that the rear brakes on your particular car don't work properly, or that all Mondeos of this era have weak rear brakes. If the latter, remember that if you were able to improve the rear wheel braking you may find that you'd easily go into a rear wheel skid on heavy braking and this would have the effect of making your car turn round. Rear brakes are generally designed to be less powerful than front brakes beacuse of this and because the weight distribution changes when the brakes are applied making the front tryes adhere more and so able to take a heavier braking force before they skid.

Rob Graham

Part of the MOT test is to look at the braking "power" on each wheel. A garage can find out if the rear brakes are working properly, but if your hand brake works, there is some breaking at the back.

If you get a grating noise from the back when you brake the brake shoes will need replacing.

I am saying that I suspect that my car has abnormally weak rear brakes, and I am going to take it to a workshop where they can measure it before it will be measured anyway at the annual inspection in spring. I suppose there may even be a limiting valve in the rear brake line to prevent the rear brakes from locking early. But they should work sometimes...

I am aware of the risk of rear wheel skid, and it is true that I have been mostly driving rear-powered cars for forty years now, so I may have forgotten how to handle a front-drive (but we have ample opportunities to practice in Finland). I lost my first car, a front-drive Citroen 11CV (eleven, not deux) by braking hard in a curve and skidding, so it leaves a memory.

Dag Stenberg

The message from "Dag Stenberg" contains these words:

Most definitely. Ain't ever seen a car without one.

Series Land Rover, no servo, no valve, single circuit, all the shoes and drums the same size (Cylinders at the front are slightly bigger). Combined with mud tyres it makes stopping fun either in wet or dry conditions..... Jon (Who stops sideways at T junctions, roundabouts, etc.)

If you made that FWD, or a front disc rear drum set up on a RWD, this would be so, IMHO. But all drum brake RWD cars of the '50s etc didn't have them.

Heck most RWD's from the 70's didn't.

I converted a ZA Magnette to front discs and had to fit a pressure reducing valve to the rear drums - otherwise they would lock up. It could be different sized cylinders would have done it but I couldn't source any.

No, in the 50's and 60's nobody had any limiting valves for the rear brakes. We used to spend several hours each year adjusting drum brakes. I have never wanted to go back.

But to my surprise after 20 years with Volvo 244 and Scorpio which both had disks all around, I now observe that a) most cars are front-wheel drive, b) a surprising number of models have only drums back there. And I gather most have this limiting valve. So I though somebody had solved the problems with drum brakes. Now I learn that people rely on the front brakes to give the braking power.

I thought two-wheel brakes went out with the 20's (when I was not around yet). Also, it is not a good idea in our parts to have only two braking wheels in winter. We need all four, and a lot of studs on the tyres too. If some people do not understand that one does not brake IN curves but BEFORE them, that should not prevent the industry from fitting good brakes. But maybe my car is just out of order and worse than the average.

Dag Stenberg

Well, yes, because you need servo to power disks, that pressure is excessive for the remaining drums. I think, however, that also all-disk systems have limiters on the rear disks.

Dag Stenberg

Pressure limiting valves are proportional to some degree even in a basic form. All four wheels brake normally at low pedal pressures, but the effort to the rears is reduced under heavier braking. Under heavy braking on a good surface weight transfer to the front requires this even on an all disc braked car.

I'd say you're car is faulty - seized wheel cylinders are quite common.

Sounds like it's out of order, all the limiting valve does is stop you locking the back wheels first.

Yeah, I was thinking of my Volvo - disks all around and no ABS (1979). The Scorpio had ABS (1989).

Dag Stenberg