Welcome to our resource for MG Car Information.
|
MG MGB Technical - Rear Brake 'Tick'
'73BGT, had brake cylinders replaced, all cleaned, new fluid, and lines bled. Driver's side rear brake has developed a "tick" when at low speeds (like in driveway or parking lot) and applying break. No tick when brake not applied. The "tick" seems to be related to rotation. Does not impact breaking, which seems to be smooth. Thanks for any ideas/recommendations, Pat |
Patrick Callan |
This could be a broken return spring. It is probably original, as are the ones on my '67. Back off the adjuster, pull the wheel and drum and inspect the braking assembly looking for broken parts. RAY |
RAY |
Patrick, sounds like a high spot on the drum, did you have them rssurfaced? If not it could cause the tick. RIC |
RIC LLOYD |
Did you torque the wheel nuts properly? I know that's an obvious one, but I had to ask. |
Daniel Wong |
Ray - checked the springs on the driver's side, they look good and are in tact. Have to check the passenger side - may be "displaced" noise. Ric - didn't have them resurfaced, but the tick seems to be too inconsistent to be a high spot - I would expect that to be present all the time. This seems to be once I have been driving for a while. Daniel - checked all the wheel nuts - all tight. I wonder if u-joints could account for this type of noise. Didn't think so, but I'll check that too. Thanks for all inputs, Pat |
Patrick Callan |
Well, I've checked everything but the u-joints so far, and the only thing I have found is that the brake on the rear driver's side was rubbing a bit (but not on every revolution) even when the brake was off. Backed off a little, so we'll see if that does anything. I would have thought that rubbing like that would have sounded different from a "tick" but... I know I've heard a sound like this before, but can't remember what caused it. Maybe the return springs are in tact, but weak? |
Patrick Callan |
Does it do it rotating the wheels by hand jacked up off the floor? Or only when driving? Did you get the shoes in the right way round? Both shoes on both sides should be the same in that they have an 'empty' portion on the steel carrier that doesn't have any friction material, and in forward motion a point on the drum should pass over this empty portion first. |
Paul Hunt |
Paul, I caught the rubbing when rotating by hand with the wheel off the floor. Minor adjustment seemed to have made a difference during a drive yesterday, but because it has been so intermittent, I am waiting to declare victory. The "ticking" sound seems only to occur when driving - and then only when using the brake at very slow speeds. Sometimes releasing the brake and quickly reapplying stops the tick. Pat |
Patrick Callan |
Guess I didn't "solve" it. No tick all the way to work in the AM, but heard it again on the way home. Only difference between the two trips is ambient air temperature, and the fact that I don't leave the parking brake on in the garage overnight, but use it in the parking lot at work. Guess my next check in the parking break linkage, to see if it is actually retracting. |
Patrick Callan |
I'll take a few more stab at it. Is the "E Clip" that holds the brake cylinder onto the backplate installed fully seated in the groove, and correctly? I might want to try and see if rotating the E-Clip would change anything. Is the hard brake line properly strapped to the axle? When you pull off the drum, are there any evidence of wear on the edges of the brake shoes? Is there brake grease on the points where the brake shoes contact the backplate? Just doing some more wondering, myself. |
Daniel Wong |
Daniel, Didn't look closely at the E clip. The parking brake line looked ok, but that was to be my next venture under the car. Didn't see any signs of bad wear on the shoes - that all looked good. Will also have to re-check for brake grease. All good thoughts - hope to get back at it this weekend. The puzzling thing is how intermittent the noise is - sometimes no noise at all for an entire drive. Other times it is audible at almost every stop. Will keep looking, and I'll check on your suggestions. Thanks. |
Patrick Callan |
Another thought is the shoe retainers - i.e. the pin that goes in from the back of the backplate, spring and clip. One of mine came free (probably because I didn't fit it properly) and did make a noise. |
Paul Hunt |
This thread was discussed between 28/08/2009 and 11/09/2009
MG MGB Technical index
This thread is from the archive. The Live MG MGB Technical BBS is active now.