Brake issue...

[Rage Page]

Hey all,

My Mk1 MX-5 just had a tough MOT one of the failures related to the brakes. I was told by the garage that there was an advisory which was a 20% breaking imbalance and this was caused due to the left disc grabbing due to being warped. So I thought fair enough, I will get the discs and pads replaced over the weekend ready for the retest.

I changed the discs and pads no problem and although a little grubby from dirt things looked fine and the refit when well with no problems(I did no change the brake fluid). However I am now noticing under heavy breaking the car is veering to the right at high speeds, less noticeable at slower speeds.

This morning when I arrived at my destination I checked the discs for temperature and both seemed about the same temperature.

I will check the tyre pressures today at lunch to make sure they are the same.

I applied grease to the slider pins and to the shims where the caliper makes contact with the pad. When I did the change I did not apply grease to the piston before I used a G clamp to push it back into the caliper. Could it be sticking? Is there anything I can do to see if I can free it up if it is before I go spending money on new seals and pistons.

Any advice would be appreciated.

Thanks guys/gals,

Page

[anonymous-user]

Front or back brakes?

[Rage Page]

Ah did I leave that bit out :S

It was the front brakes that were the issue in the MOT and the ones I replaced.

[anonymous-user]

Ok, just checking when you mentioned you pushed the piston back in with a G-Clamp, that's a no go with the rear calipers as they need wound back.

I suffered the same problem as you seem to be on the front, and could never feel one disc hotter than the other either, however it was caused by one of the caliper pistons sticking, not completely stuck but enough restriction in movement to cause an imbalance.

First thing I did was remove the calipers whilst leaving the brake lines attached, and have a good look around the piston dust boots (you may need to pump pedal to push pistons out to properly examine the dust boots), if one or both dust boots are split/damaged chances are water/dirt etc has got in and the outer surface of the piston has got corroded and is sticking - this means reconditioning your caliper with new piston and seals, or just buy a reconditioned exchange caliper.

I reconditioned and bought the parts from here http://www.brakeparts.co.uk/ but a recon caliper is nearly as cheap and much less hassle!

[Rage Page]

Thanks for the info that is good to know.

I will take it apart and give it a good clean and make sure everything is greased up where it needs to be. Hopefully its just that as things seem to have improved a bit today.