Today was a good day, motor-wise: successfully rebuilt the rear brake calliper that I removed and stripped on Sunday, and put it back on the car.
As noted in a previous blog entry (here), the nearside rear calliper was seized on the upper slide bolt; I believed this was the cause of a nasty squeaking noise that had developed of late.
Last Saturday, I removed the calliper and mounting bracket assembly from the car and started applying liberal doses of penetrating oil every few hours and overnight. Sunday afternoon, I set to to try and free the calliper from the mounting bracket. This proved to be very difficult, but I persisted with progressively larger hammers and eventually it began to move, just a little. There was considerable satisfaction when they were finally separated! (And I only hit myself with the hammer once.)
Cleaned up the corrosion on slide bolts and in the upper bolt socket of the calliper. Then removed the piston and bleed valve and gave the calliper a thorough clean with brake cleaner and meths. The piston and upper slide bolt dust seals were knackered, so ordered a refurbishment kit from MX5 Parts. (Arrived with the usual promptness – they really are a good supplier.)
Rebuild of the calliper went pretty smoothly – getting the piston dust boot on was a bit tricky, but managed OK thanks to “special tool” recommended in Rod Grainger’s Enthusiast’s Workshop Manual (can’t recommend that book too highly!)
A short road test indicates the squeak has gone and the brakes still work, albeit with a bit of a pull to the left and a tendency to lock the nearside rear on really hard braking – hopefully only temporary until the pads reseat themselves.