Fluid brakes

Tim M · 03 April 2006, 22:27

Can anyone tell me anything about fluid trailer brakes?

Are they hard to maintain? Why would you have fluid brakes on a trailer over cable?

Thanks

ian parkes · 04 April 2006, 00:00

Similar to your cars brakes . Master cylinder is operated by the pressure on the tow coupling when the towing vehicle lows which pushes the fluid to the brakes .
Much better than cables as the braking force is greater and more even , no cables to stretch and break , less likely to sieze ,self adjusting etc etc
Hence the reason cars use fluid brakes

they should be easier to maintain . If you are able to service the brakes on a car with drums on the back then your trailer will be similar
If you are not them maintenance of iether system should be left to a professional .

Nos4r2 · 04 April 2006, 00:07

Not sure they are a really a good idea if a trailer is going to be submerged? I know that in theory the system is sealed but...

ian parkes · 04 April 2006, 01:04

Quote:

Not sure they are a really a good idea if a trailer is going to be submerged? I know that in theory the system is sealed but

What is a good to submerged in salt water ?

A cable is far more likely to sieze than a slave cyinder or master cylinder . Look at older cars if anything had packed up its the cable hand brake . So long as you put a little grease behind the rubbers in the wheel cylinders it is pretty well sealed .

Nos4r2 · 04 April 2006, 01:08

I'm thinking more of water in the brake fluid. It's kinda obvious when you've got a problem with cable brakes if something isn't working, but brake fluid with a significant ingress of water will boil.

ian parkes · 04 April 2006, 01:25

Very true but how is the water going to get in there unless the seals are gone in which case its leaking fluid .
You would need a breather on the master cyl if you were going to submerge the whole thing .
4x4's get driven deep in water and the brakes are the least of thier problems .

codprawn · 04 April 2006, 04:09

Very true - hydraulic systems have to be sealed very well - if they aren't they just stop working very quickly!!!

Scary Des · 04 April 2006, 07:59

Quote:

Originally Posted by Tim M

Can anyone tell me anything about fluid trailer brakes?

Are they hard to maintain? Why would you have fluid brakes on a trailer over cable?

Thanks

Tim they wouldn’t be legal on there own, you would need a mechanical handbrake and water ingress can be a real issue. The lip seals are designed to keep pressure in, not out so when your trailer is a couple of metres underwater, with no pressure in the brake system, the water pressure could be enough to force water past the seal

Des

Jono · 04 April 2006, 08:25

Quote:

Originally Posted by Scary Des

...so when your trailer is a couple of metres underwater, with no pressure in the brake system, the water pressure could be enough to force water past the seal

Des

I feel that if your trailer is submerged "a couple of metres".. the last thing on your mind will be worrying about your trailer brakes....

jwalker · 04 April 2006, 11:07

My previous trailer had hydraulic brakes. Unless you are able make parts yourself, give them a miss. The rubber boots on the wheel cylinders are not completely watertight and the cast iron cylinders quickly rust to the steel pistons. I made brass pistons with a second seal and larger diameters so the boots sealed properly. They were filled with brake grease and worked well after that. Water entering the master cylinder was not an issue because it was virtually at the backend of the car and never got immersed. Copper brake pipes need to be used.

On my present trailer, I've done away with the cables and substituted a rod system and in works well. I rate it better than the hydraulics.