Brake calipers.
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jmec
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Anyone recommend a good exchange brake caliper company?
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daimlerman
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I have always used my local Partco,now known as Unipart.
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jimbom30cab
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Gavla
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bigred, not cheap but looks like they do a proper job.
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jmec
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Thanks for the replies. I've got the offending caliper off. It wasn't backing off the disc enough. Not tight on and therefore overheating and pulling the car over but just rubbing enough to give off an anoying squeak. What to do next? Change the piston seal? The piston looks ok but the caliper looks like it's been at the bottom of the sea for a decade! I'm thinking the condition of the sliding parts would affect the caliper movement. Any thoughts or similar experience tales would be appreciated. Thanks....
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Grrrmachine
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If you've got the time, strip the caliper down, rig up a basic electrolysis tank and de-rust it. Electrolysis is very, very easy to do, and afterwards a simple scrub with a brasswire brush will see the external rust flake off like dandruff.
Then paint the caliper with a paint of your choice, and reassemble with a decent rebuild kit (I bought mine for a fiver). Buy some decent brake lube like ATE grease, and you'll find that the caliper slides smoothly just like it did from the factory.
I rebuilt a sticky caliper like that over a weekend, and haven't had any trouble since. The costs were the paint, the rebuilt kit, the grease and a sachet of soda for the electrolysis tank.
Then paint the caliper with a paint of your choice, and reassemble with a decent rebuild kit (I bought mine for a fiver). Buy some decent brake lube like ATE grease, and you'll find that the caliper slides smoothly just like it did from the factory.
I rebuilt a sticky caliper like that over a weekend, and haven't had any trouble since. The costs were the paint, the rebuilt kit, the grease and a sachet of soda for the electrolysis tank.
Last edited by Grrrmachine on Sun Oct 06, 2013 4:35 pm, edited 1 time in total.
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jmec
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Mmmm interesting, thanks for that. J
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Rob_farmer
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Would you know any resources where I can read about it ?Grrrmachine wrote:rig up a basic electrolysis tank
I`m driving E30, 1989, 325i, 4 door. Restoring 1990, 4 door.
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Grrrmachine
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Brianmoooore
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Things the two links above may or may not mention: Multiple anodes surrounding the object to be de rusted are good. The main action takes place on the part of the rusty bit nearest to the anode, with very little happening on the side facing away, so the more of the part you can get facing an anode, the better.
Old brake discs make excellent anodes.
No damage will occur if the rusted object is left in the tank with the current flowing after all the rust has gone.
The croc. clip on the object you are de rusting can be submerged in the solution, but the positive croc. clip on the anode must be out of the liquid.
My own 50 gallon tank is merrily bubbling away as I type, and is hardly ever turned off. Always something needs cleaning up.
Old brake discs make excellent anodes.
No damage will occur if the rusted object is left in the tank with the current flowing after all the rust has gone.
The croc. clip on the object you are de rusting can be submerged in the solution, but the positive croc. clip on the anode must be out of the liquid.
My own 50 gallon tank is merrily bubbling away as I type, and is hardly ever turned off. Always something needs cleaning up.
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DanThe
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Ive always found GSF the cheapest for reconditioned calipers
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aimlessrock
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ive just finished overhauling my rear calipers using electrolysis..not difficult at all.
give it a go Rob..
give it a go Rob..
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190 Mercedes (1988)
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G-Bear
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I didn't go down the electrolysis. But did overhaul my calipres using Big Red's kits. Having failed its MOT on brakes the first time round, it sailed through the second time after an overhaul. I think the kits in total came to about £50.
I'd be temped to try electrolysis treatment if I were to do it again.
I'd be temped to try electrolysis treatment if I were to do it again.
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jmec
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Thanks for the updates & electrolysis info'. I'll give it a go. J
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milescook
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I tried some electrolysis and it worked great at removing rust. Unfortunately it seems that one of the main bolt holes was mostly rust and a chunk came off where the bolt would sit. It went in the bin..
The story so far... http://www.cookracing.co.uk/
Also please help the race budget by watching some videos
https://www.youtube.com/cookracinguk
Also please help the race budget by watching some videos
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jmec
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Best to find out that way than when you're shifting down the B
roads! I had such an experience some time back and although I wasn't driving too fast it certainly drew my attention. The thread was 'gone' on one of the caliper bolts. In a short time it worked its way loose and out. The centrifugal force shot it into the inside of the wheel where it pierced the alloy where instant deflation of the tyre resulted. Good job I had a clean pair of pants on standby!!
roads! I had such an experience some time back and although I wasn't driving too fast it certainly drew my attention. The thread was 'gone' on one of the caliper bolts. In a short time it worked its way loose and out. The centrifugal force shot it into the inside of the wheel where it pierced the alloy where instant deflation of the tyre resulted. Good job I had a clean pair of pants on standby!!
