www.jec.org.uk

Hello,

I've had my Daimler 4 months now and the brakes, particularly the rears, regularly make driving it an edge of the seat experience. If they are used to brake from a high speed or in stop start traffic their usefulness deteriorates and sometimes the peddle feels like it has no effect at all. They also get incredibly hot and if I open the window or door I can smell them burning from the rear. On occasion I've even seen them steaming. I suspect that they are sticking because sometimes speed is limited while the engine is keen to get going. Can anyone recommend resolutions or even a modern upgrade that would make them more efficient and effective?

The old XJ6/12 and Daimler equivalents had excellent ventilated discs at the front and adequate, if badly ventilated, solid discs at the back. (The rear brakes are really only for show anyway, there's so much weight transfer under braking.) Not as good as 21st century, but well up to normal usage, and as far as I know, there's no need to upgrade even if you go racing. If you are smelling hot brakes when crawling in a jam, they're almost certainly binding. If that's all that's wrong, identifying and fixing should be relatively easy. If it's a while since the brakes were serviced (they should have been flushed with clean fluid and had the flexible hoses replaced about every 30,000 miles by memory, and if you're keen, replace ALL seals every 60,000) it may well be advisable to overhaul the entire break system.

It's a while since I had one, but exchange callipers and master cylinders used to be readily available and reasonably priced. You could also get overhaul kits if you have the patience, but if the bores are rusted you might need to get exchange units anyway. While you're looking at the callipers, you may well find the disks are heavily worn - again replacements are available at reasonable price from suppliers such as SNG Barratt. Also, it's almost certainly worth replacing the flexible hoses, and be prepared to replace some of the steel piping. Having tried to sell you on the task, one of the hardest parts is getting the handbrake adjusted correctly after changing the rear disks. But the trick, which is pretty straight-forward, if heavy, is to drop the rear suspension subframe and do it all outside the car.

Good stuff there Paul.
We would always go down the route of refurbed Callipers. For the cost against the time it takes to do the job - a pair of nice new units are well worth it.
Check for oil leaks too. If the rear brakes are getting really hot, you run the risk of damaging output bearing seals, and will soon detroy the output bearings too.

Kind regards,
Keith

Hi
Just thought I would add a coment about sticking brakes.
A friend of mine had exactly the same problem with one rear brake on a Silver Shadow.
He tried everything, servicing the hub, stripping the caliper etc.
Turned out to be the hose had collapsed inside. So might be worth trying until you have time to drop the rear sub frame.
Also I think hoses are meant to fail internally with age rather than burst.
Hope this helps
Simon.

I had a rear brake overheating problem with a 4.2 XJ6. The rear brake pipes had collapsed internally allowing the fluid to push the calipers on but would not easily allow the return. Changed the hoses - fixed. Check for any other damage that could have been caused by the excessive heat!!! Alec Gurney.