mad85

Active Member

• Nov 25, 2019

• #1

I had noticed the brakes are not so good and feel a little mushy. For instance an emergency brake does not feel so 'urgent'...

I also had an instance when going down a mountain quite fast and lost brakes at one point due to them overheating (with steam coming off the front calipers and some where under the intake manifold). Since then I got an overhaul kit for the calipers (they needed it), fitted ebc brake pads and fitted new bearmach drilled/slotted discs all round.

Yesterday however, after an hour of hard driving i also started to feel the brake pedal going hard and started loosing brakes. No steam this time but there was a smell and had very little brake assist.

Is there anything wrong with my brakes or is there anything i can do to improve this?

Thanks
Mark

 

Kev12

Well-Known Member

Full Member

• Nov 25, 2019

• #2

Sounds like you have cooked your brakes again. If there is smoke coming off the pads then I'd say ther brakes are working well enough but you need to drive more carefully under extreme situationsto stop them getting so hot.
I have cooked brakes on a D1 once, going down this hill https://en.wikipedia.org/wiki/Porlock_Hill towing 2t. The pads will recover soon enough from normal driving but if the brake fluid is old and has boiled then the pedal will stay spongy until it is bled. New fluid would be a good idea

 

mad85

Active Member

• Nov 25, 2019

• #3

i guess replacing with dot 5.1 wont be a bad idea, right?

 

Kev12

Well-Known Member

Full Member

• Nov 25, 2019

• #4

I think it would be ok, but no real benefit. I'd stick with 4 as it's easy to get and cheaper

 

Europa486

Well-Known Member

• Nov 25, 2019

• #5

Dot 5.1 is used with ABS systems but perfectly ok with earlier DOT4 systems as well,
But a complete fluid change is your first priority as brake fluid is hygroscopic and will absorb water over time,
With heavy braking that water will turn to steam and is compressible so your brake pedal will get very spongy,
I would also check if your servo is working well and your servo vacuum pipes are good especially the small feed one to your heater,

 

Pawl

Well-Known Member

• Nov 26, 2019

• #6

Check your rear brakes are working correctly. If they're not, your fronts will be doing far more work than they're designed for & will overheat.
If your fronts needed overhauling, I'm sure the rears will too as they usually deteriorate faster.

 

mad85

Active Member

• Nov 26, 2019

• #7

Thanks for the comments. How do i i check vacuum servo?

 

Interceptorxj

Well-Known Member

• Nov 26, 2019

• #8

With the engine switched off apply the foot brake hard down then holding the foot brake hard down start your engine, if your servo is working you should feel the pedal go down slightly further as the servo assist kicks in.

 

mad85

Active Member

• Nov 26, 2019

• #9

Yes, that works

 

Europa486

Well-Known Member

• Nov 26, 2019

• #10

Yes but if you have a vacuum leak from servo or hoses or duff vacuum pump then the first application of the brake
Will often work ok but subsequent applications will make the pedal hard and unresponsive , requiring much greater effort from you to stop,

 

mad85

Active Member

• Nov 26, 2019

• #11

Europa486 said:

Yes but if you have a vacuum leak from servo or hoses or duff vacuum pump then the first application of the brake
Will often work ok but subsequent applications will make the pedal hard and unresponsive , requiring much greater effort from you to stop,

Click to expand...

That makes sense, as that is quite similar to what i m experiencing. Any tips on finding the leak?