ND - dead in the water - (willwood?) Brakes!

Technical Area Wheels, Tyres & Brakes
1

ND1 2016

got the willwood 6 pot up front.

to keep short:
6 weeks ago, track day. warped discs.

  • changed rear discs and pads. pads needed doing, but didnt fix warp issue (car shuddering)

  • changed front discs. warp issue fixed.

  • new issue - even after bed-in brakes soft and not biting well. needing alot of pedal travel.

  • brake system not ‘opened up’ during any of the above.

  • begun to bleed brakes. air came out of 1 willwood corner.

  • then, mistake while working around the corners - forgot to top up reservoir. pumped air into the system!

now the problem

  • spent 2-3 hours now, doing 4 laps of the car. bleed all the corners. i have had 3 mini air bubles from one rear corner. as soon as i crack a nipple, fluid flows.
  • but, brake pedal will NOT firm up with engine off.
  • brake pedal with engine on hits the floor easily. no pressure at all.
  • no air from any caliper. only fluid flowing whhen nipple open.
  • loud air hissing sound when pumping. coming from, i think, UNDER the engine.

■■■?! help. had enough of this.
car is now technically broken down. theres no way i can even limp it to a garage in its state.

2

Have you bled the clutch?

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3

no….

i will ask ‘why?’ but feel i need to google this tomorrow….
do they share a master cyinder? oh man

4

They do indeed!!

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5

Look here BRAKE FLUID AIR BLEEDING | 2016 ND Shop Manual

Try the rear calliper removal/rotation method shown lower in the article.
:heart:

6

ah i will try this next.
hadnt thought about the rear piston.

7

Personally, I would just drain all the brake and clutch fluid.

Completely starting from fresh.

I even took off the clutch slave cylinder and Brake Master Cylinder to check everything.

You can never be too cautious with brake systems.

Similar problem in my NC a few years back where the air wouldn’t bleed from the clutch system.

(As already stated above shared master cylinder).

Pressure bleeder is ideal along with a good friend that keeps it topped up ALWAYS.

Air can get caught up in the ABS pump too.

I did the clutch first.

RNS, ROS, FNS and then FOS.

I did initially think the Master Cylinder had broken, but no it was that pesky air.

That sorted it and no trouble since,(Brake fluid change in March next year).

PS, I assumed you know you have to wind the rear piston/s back in on standard brakes. I don’t know what your current ones have.

8

If you ran the system ‘dry’ then doing the rears is a must. Hope it works for you.
:heart:

9

Maybe wrong, but perhaps doing something that has escalated into above your spanner pay grade.

If you are with say Green Flag, explain the situation and they “might” recover it to a suitable garage.

Mate with a car trailer?

Web search on a chap that works from a mobile van that can come to your house?

Quite a few good ones about that know their stuff.

Never give up.

10

I’d stick with OEM, bought from Mazda. No issues thus far.

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11

having another go at it tonight. got an extra set of axel stands so i dont need to keep lifting front/rear/front etc.

all wheels off now. waiting for the +1 to come help in the cockpit :smiley: will be a full brake disassemble.
i’ll have a mild breakdown if it gets to the weekend and the only 4 wheels i can drive is a 2 ton Kia :smiley:

12

all 4 corners done. fully disassembled all the calipers. reset pistons front and rear. followed the guide.

nope. still full of air. ive got no brakes, no handbrake either. :frowning: . no air bubles on any caliper corner though. all flowed full of fluid as soon as the nipples were cracked.

will get it towed to a garage.

thanks for help guys. guessing this must be a master or slave cylinder thing. but ive had enough ‘troubleshooting’. spent hours on this and not getting anywhere with it.

13

If you’ve let air in at the master cylinder end, you have to keep bleeding until the air has a chance to make its way all the way from the m/c to the caliper - there will be a lot of bubble-free fluid first.

2 Likes
14

Just out of interest how much brake fluid have you put through the system since running the MC dry?

Please let us all know how you conquer this situation so we can all learn.
:heart:

15

Sounds like you may have air trapped in the ABS pump after running the system dry, ( hopefully you have not caused damage to the master cylinder) you could try jacking the rear of the car, so the wheels are free of the ground and let the car drive in 1st gear, then press in the clutch and brake gently, causing the ABS pump to function and cycling the valves, then re bleed the system to see if that improves things.

Best of luck.

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16

Shared master cylinder: That can’t be right? Do you mean they share a reservoir?

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17

Yes they do share the same MC Reservoir.

18

good news - got the air out, got the brakes working.

in the end just sat at one rear wheel (drivers side) and just pumped, pumped, pumped. after about a dozen flows of all fluid, pilot just ‘oh that felt firmer’ and then on the next nipple crack air flowed through the tube at a rate of notes!

after that, regular bleeding resumed. :slight_smile:
been for test drive all sorted.

10 Likes
19

Good news and as I said never give up and you will probably never make that mistake again.

I was convinced that air got trapped in the ABS pump.

I won’t! :wink::+1:

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