5 replies to this topic

[Mikey7094]

Hi

My front calipers are sticking a bit, so that the wheels are a bit stiff to turn by hand. I know the calipers could do with a proper rebuild, but I'm looking for a more short term fix (there is an outside chance I might be able to drive it to Castle Combe).

I just want to free the pistons up a bit. I gather WD40 is not good for brakes, so is there any other way of loosening them?

Any suggestions appreciated!

Mike

[Cooperman]

It has been said that if you take the pads out and push the pistons right back, then pump them a little way out, limiting their travel with some sort of wedge and do this for each piston in turn it can help, especially if you spray a bit of WD40 onto the piston when it's out as far as it can safely come, then this can free the pistons off a bit.
This is a bit of 'witchcraft' really as sticky brakes should be attended to properly with a full calliper re-build. Nothing else is really safe.
It's your choice.

[Skortchio]

As said, if they're sticking then it can be an early sign that you need to give them some loving.

Things like WD40 are fine as long as you don't put it near the pads, take them out in advance.

Pop the pads out, drop a bit of wood between the pistons and push the pedal once or twice at best to show more piston than has been used, give the pistons a decent dousing in brake cleaner and a clean up with a green scouring pad to remove the grime, a quick squirt of WD and you're done.
Then take the cap off your brake fluid resovoir, and using the wood push the calipers back until there's about 5mm protruding.

Then pop your pads back in with some copper grease on the backing plates to help eliminate squeal, calipers back on hub and pump the pedal until you get braking again.
Check the fluid level is okay and top up if needed.

[Midas Mk1]

I wouldn't want to be doing a quick fix on brakes, if in doubt do it properly.

[Skortchio]

The method I gave isn't so much a quick fix but more how to eliminate stiffness in the calipers from build up of grime. It's common practice on motorbikes, which owners generally pay far more attention to than car owners (Mini's excluded of course ).

It will also show up if your calipers are stiff from mechanical issue too, such as perished seals.

[Ethel]

You'll get a better idea if you pump the pistons out a bit. The fluid seal is quite a way inside the caliper, it's usually the dust seal that sticks; a bit of corrosion near the top of the piston won't hurt as long as there's some good condition plating further down for the fluid seal to run on. Scrub the visible rust off and work the pistons to & fro to wet the seals - a big spanner makes a handy lever.