bankz5152

bankz5152

Well-Known Member
I seem to be having an on going poor braking issue! Can't quite figure out what it is...

I had the standard lines changed for +2 SS braided beginning of the year, along with some of the copper piping that was shagged. Since I've also changed all the brake pads for Ferrodo, the discs are all in good nick, not warped or scored, also changed the passenger side rear calliper due to a sheered bleed nipple.

The system was bled by the garage, then I bled it again. Each time the brakes feel good for a short run then back to poor again.

Basically if I put my foot down to brake it goes almost to the floor before any real braking occurs, usually I have to preventively pump the pedal a few times to get a nice hard pedal and some actual stopping power!

I've checked all the unions and lines around the callipers and the like, no leaks as far as I can tell.

I did notice some fluid below the brake master on top of the air intake, though I am unsure as to what fluid this is. So I have cleaned up the area and will monitor.

Nanocom shows no ABS related fault codes and all the readings are as they should be as far as I can tell.

I think the servo is fine as car off, foot down on the brake, start car, pedal moves down.

I wondering if the master is drawing in air?

Any ideas?

Thanks
 
Pistons all free in the clippers? Finish bleeding by pushing the pistons right back in the calipers(one at a time otherwise reservoir overflows) to see if a bubble comes out.

If you're absolutely sure it's bled properly then I'd look at the master cylinder. Seals maybe leaking.
 
Going to give it another full bleed this week and see. Good tip! I do hate taking my wheels off though :rolleyes:

Anyone ever used the power bleed function on the Nanocom?
 
Check for the usual culprits first, leaks on the master cylinder and calipers. It could be a seal on its way out. When you bleed the system next, I'd change the fluid completely, old fluid can soak up moisture from the air, but that usually causes "brake fade" which is the opposite way round to your symptoms, they're more indicative of a failing seal.
 
What would a leak on the master look like?

Since the lines where changed in Jan I think I've put 2.5L - 3L of fluid through the system, so I should need to drain and refill.

@jamesmartin Yes that did happen, should it?
 
If the master cylinder seals were poor you wouldn't necessarily see an external leak but as JM says above, you might be able to see some turbulence in the reservoir. Looks like it's time for a new master cylinder. It might be possible to mess about changing little rubber rings but when mine was getting tired I just bought a new one.
 
@bankz5152 Well, it's approaching nine o'clock and I'm just procrastinating, putting off starting work. Plus these are all jobs I've done on mine over the last few years so I'm interested to see how you get on.
 
Hahaha exactly what im doing! Cheers.

Any tips on changing the master? Worth changing the servo at the same time?
 
bankz5152 said:
Hahaha exactly what im doing! Cheers.

Any tips on changing the master? Worth changing the servo at the same time?
Click to expand...

As you can see, mine's a bit different to yours in that mine is standard rather than ABS, but the general idea should be the same. It sounds like you're getting some assistance from your servo so it's probably alright. If you yank the air hose off it (it's only a push fit so you won't do it any harm) and hear the air whistling as it rushes in, it shows it is holding vacuum. I replaced mine because I wasn't sure it was helping me. Again, I could mess about with trying to source and replace the rubber components, or buy a new one. In the event I did the latter.
 
@Brown Great read! I love the discs are they EBC discs? I was considering them for my 110, thinking about it I should probably consult the Haynes manual as well, the 110s getting on to 97k now... Just been excited by fitting shiny fun bits :p
 
Yes, I got EBC discs and pads. I just replaced the pads the other day after about 4 years. They weren't right down to the metal but just getting a bit thin.
 
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