Binding Front Brakes

[neil-yaj396]

I've read a couple of posts on this issue but still aren't quite clear on the fix. I understand that it can be caused by faulty servo or incorrect adjustment of the master cylinder rod ().

Am I right and in the case of the latter how is the adjustment corrected?

(I haven't bought a Fulvia btw, asking for Ms. Hudson).

[chriswgawne]

In my experience, with S1 Fulvia brakes it can also be caused by a worn master cylinder or worn m/cylinder seals not allowing the insides to reset back to resting position. I think the inside surface of the master cylinder has to be very highly polished which is very difficult to do oneself. Ideally after rebuild, one should run a sequence of bench tests with the m/cyl connected hydraulically to a wheel cylinder .
Chris

[lancialulu]

Also how old are the Dunlop callipers? The Piston rubbers get stiff and stop the pads from receding off the disk. Are the front disks just getting hot/warm or are they locked on? Is there a servo?

[Dikappa]

often the problem has been in the flexible lines, on pedal pressure the oil gets through, but it can't get back if the flexible hoses are worn.

[neil-yaj396]

Thanks for the replies. I should have said that it is a Series 2 (1971) car with a servo and the brakes and flexible lines were rebuilt/replaced about 5 years ago, though only a few thousand miles in that time, hence my thoughts of maladjustment rather than wear and tear. This has happened before but was looked at by a mechanic who seems to have managed a temporary fix.

The brakes are fully binding with a solid pedal rather than just dragging and heating up the disks.

(to paraphrase Alan Cooper "Don't swap a Beta for a Fulvia. You are always having to fix them......")

[lancialulu]

first check the pedal push rod but there is a second push rod sort of adjustable between the servo and the master cylinder. A quick test is to loosen the master cylinder and space it off the the servo with ideally some half moon (cut) washers about a millimetre or so. If the problem goes away (it is caused by the seal not returning back and opening the feed port to the reservoir) the part the master cylinder away from the servo and carefully screw back the tiny push rod protruding from the servo.

[davidwheeler]

If you find that releasing the nipple on the brakepipe/master cylinder relaxes the brakes it is likely the servo pushrod is too long.   Happened to me.