Opinions on cam belt replacement and brake fluid

Stubod

A brake fluid change means replacing the old brake fluid with fresh , it's exactly the same definition as doing an oil change 

There's no mystery about it and it's very quick and easy for garages to change fluid 

I would be interested to know what the garages actually do? eg do they just drain (suck out) the reservoir and re-fill it, or do they go to the bleed nipple on each wheel and draw it out while topping up the reservoir?

I am aware that some garages use a suction pump to remove the engine oil from the filler hole rather than drain it out by removing the drain plug?

HansOndabush

Homer_home said:

HansOndabush said:

Homer_home said:

If your brake fluid is old and has water in , when the brake fluid gets hot it will bind your brakes and eventually they will lock on , until they cool down then they will release 

You can tell when your fluid needs changing as on a hot day your brakes will be a lot sharper and require less pedal travel to brake 

Complete nonsense; not even worth a proper reply.

No it's not, and the reason you won't reply because you only think it's nonsense because it doesn't make sense to you 

Just to enlighten you water expands when hot , therefore if your brake fluid has water in it (because the majority of brake fluid is hygroscopic) in hot weather the water will expand and bind your brakes and eventually after long enough will lock your brakes and you will have to wait until your car cools down to release the brakes  (normally you have to wait until it's dark) 

A simple brake fluid change will solve this

And how did I find this out ... It happened to me.... And yes once I changed the brake fluid ..... Problem solved 

So please again tell me how is my post complete nonsense?

.

It is nonsense because otherwise no-one would be able to compress the caliper piston when changing brake pads. Excess fluid returns to the master cylinder which is why you are advised to remove some fluid from the master cylinder before compressing the caliper piston so as to avoid spillage of brake fluid from the top of the master cylinder.

If your car's brakes locked up in hot weather then you had some other problem with the brakes or a very non-standard braking system.

There is always a flow path back to the master cylinder otherwise once you applied your brakes, they would never come off again!

DiddyDavies

Homer_home said:

HansOndabush said:

Homer_home said:

If your brake fluid is old and has water in , when the brake fluid gets hot it will bind your brakes and eventually they will lock on , until they cool down then they will release 

You can tell when your fluid needs changing as on a hot day your brakes will be a lot sharper and require less pedal travel to brake 

Complete nonsense; not even worth a proper reply.

No it's not, and the reason you won't reply because you only think it's nonsense because it doesn't make sense to you 

Just to enlighten you water expands when hot , therefore if your brake fluid has water in it (because the majority of brake fluid is hygroscopic) in hot weather the water will expand and bind your brakes and eventually after long enough will lock your brakes and you will have to wait until your car cools down to release the brakes  (normally you have to wait until it's dark) 

A simple brake fluid change will solve this

And how did I find this out ... It happened to me.... And yes once I changed the brake fluid ..... Problem solved 

So please again tell me how is my post complete nonsense?

.

I will tell you why.
Yes, water expands when hot but  then again, so does brake fluid (and engine oil, clutch fluid, power steering fluid etc).
The expansion of brake fluid had no effect on the brakes simply because when it expands, the level in the reservoir will rise as the extra volume of fluid is fed back into this reservoir.
Water in the brake fluid will not cause the brakes to bind or lock up. In fact, it has the opposite effect in that if the fluid gets too hot, the brakes get less effective and the pedal starts to get spongy.
This is because the water contained in the brake fluid boils at a far lower temperature than the fluid and it can turn to steam.
Steam being a gas is very highly compressible so if there is steam in the brake fluid and you press the brake pedal, the steam will compress before the hydraulic pressure is transmitted to the wheel cylinders so you need to apply more pressure to the master cylinder to counteract the extra compressibility of the fluid.

AdrianC

DiddyDavies said:

Homer_home said:

HansOndabush said:

Homer_home said:

If your brake fluid is old and has water in , when the brake fluid gets hot it will bind your brakes and eventually they will lock on , until they cool down then they will release 

You can tell when your fluid needs changing as on a hot day your brakes will be a lot sharper and require less pedal travel to brake 

Complete nonsense; not even worth a proper reply.

No it's not, and the reason you won't reply because you only think it's nonsense because it doesn't make sense to you 

Just to enlighten you water expands when hot , therefore if your brake fluid has water in it (because the majority of brake fluid is hygroscopic) in hot weather the water will expand and bind your brakes and eventually after long enough will lock your brakes and you will have to wait until your car cools down to release the brakes  (normally you have to wait until it's dark) 

A simple brake fluid change will solve this

And how did I find this out ... It happened to me.... And yes once I changed the brake fluid ..... Problem solved 

So please again tell me how is my post complete nonsense?

I will tell you why.
Yes, water expands when hot but  then again, so does brake fluid (and engine oil, clutch fluid, power steering fluid etc).
The expansion of brake fluid had no effect on the brakes simply because when it expands, the level in the reservoir will rise as the extra volume of fluid is fed back into this reservoir.
Water in the brake fluid will not cause the brakes to bind or lock up. In fact, it has the opposite effect in that if the fluid gets too hot, the brakes get less effective and the pedal starts to get spongy.
This is because the water contained in the brake fluid boils at a far lower temperature than the fluid and it can turn to steam.
Steam being a gas is very highly compressible so if there is steam in the brake fluid and you press the brake pedal, the steam will compress before the hydraulic pressure is transmitted to the wheel cylinders so you need to apply more pressure to the master cylinder to counteract the extra compressibility of the fluid.

Somebody who paid attention to physics lessons at school...

Norman_Castle

Homer_home said:

photome said:

Thanks for comments guys. Will et the cambelt done. most likely the brake fluid as well , but I dont normally agree with Fred but how does water get in a sealed system, and in days gone by 70s and 80s and 90s I dont recall changing fluid on cars that I had for a few years and back then I used to do most things myself
ps Seat give a 5 year warranty on the cambelt if they do it

Brake systems aren't sealed , they can't be , there's a hole in the reservoir cap to allow the fluid to drop when your brakes wear 

Mines sealed, there's a flexible rubber dome inside the cap which deforms to match the vacuum in the system.