New Build R400 Brake Bleeding

[andrew_r]

Can anyone help

 

I have bleed the brakes a few times.

 

Now I have finished the brake pedal goes quite a long way before it goes firm. I see all these things about no movement and roack hard etc.

 

The brakes don't pump up at all.

 

Is this normal on a new build? Or do I still have some air in or a leak.

 

I have big brakes and uprated master cylinder

 

Thanks

Andrew

[Stationary M25 Traveller]

Are the front calipers fitted the right way up with the bleed nipples at the top ?

 

Have you noticed there are two bleed nipples on each big brake at the front ?

 

Rear std calipers can be tricky. Tap with hammer while bleeding to dislodge air bubbles, or remove calipers and tilt so bleed nipples upwards. Hold piece of wood between pads to simulate brake disc, to stop pistons popping out of caliper !!Caution ref fixed brake pipes though !!

 

Are the rear brakes fitted correctly with the raised part on the rear of the brake pad seated in the slot in the piston ? Handbrake adjusted correctly ?

 

 

[NoLimits]

The uprated master cylinder should be imediately hard. Very little travel.

 

I would suggest some air remains in the system. It can be hard to flush out. Have you used a bleeding kit or did you do it the old fashioned way? The bleed kits are really quite good.

 

 

 

A Blast from the Past

www.7tips.co.uk

[elie boone]

Just try to get the brakes warm by driving, beware no emergency stops just normal braking, this way the whole system can settle, you might find the odd buble comming out when bleeding again.

BTW make sure the brake pads can move freely in the calipers

[CJS]

I had the same issue with mine until (as SM25T notes) I spotted that cheeky second nipple on the front calipers. No problems after that.

 

Chris

[andrew_r]

Thanks all for your suggestions.

 

I had spotted the two nipples on the front.

 

I'll try and tap the rear calipers whilst rebleeding.

 

I don't like this brake fluid stuff, makes me worry about the paintwork.

 

Regards

Andrew

[MADMALC]

An 'Easy Bleed' will make things easier and more reliable than pumping. It is a good investment for life.

If you fear the fluid going all over the place you can still use the 'Easy Bleed' just do not fill it with liquid. Just use the master cylinder reservoir and keep disconnecting and topping up.

Mine did bed in a bit after a few hundred miles.

 

S7MAD

[Rattie]

We've been somewhat challenged by bleeding our R300 brakes. The pedal still feels a little soft, but it's the standard MC not the uprated, so I'm not sure quite what it should feel like. We're taking the car for PBC on monday, so we're getting CC to have a look at that also.

 

One thing that I was puzzled by was the manual instructing us to do the inboard nipple first, then the outboard. That seems a little odd as surely if a bubble comes through the inboard cavity on the way to the linking pipe during the outboard bleed it may decide to head upward toward the inboard nipple, just to keep the pedal nice and spongey.

 

We gave it another bash this evening before I adjusted the handbrake, and this time did it outboard then inboard. Seems fair now, but we'll have to see later when we try torqueing the rear hub nuts again - this time with handbrake also.

 

Martyn

^{_{R300GRR SV nearly there!!}}

[andrew_r]

That sound like a good idea to use the Ezibleed with an empty bottle. I was avoiding an eazibleed for the reason you state.

 

Probably try once more manually tapping the rear calipers.

[elie boone]

Never had a problem bleeding the brakes by pumping the pedal, just make sure you use a tube that's a good fit on the nipple and that he tube end is submerged in the receiving bowl.

If i bleed 4pots then i open the inside nipple first until some brake fluid comes out then i open the outside one until the brake fluid comes out. I do both wheels this way before i actually start to bleed.

Sometimes on a DD rear caliper i use an airpressure gauge on the reservoir ( max 1 bar ) to bleed the brakes.

 

I have also a profecional bleeding divice witch works good but i just don't use this anymore, a tube and a hose is just as good with less hassle.

[sjmmarsh]

- just to get all the GTKY:CSR posts together.....

[Myles]

One thing that I was puzzled by was the manual instructing us to do the inboard nipple first, then the outboard. That seems a little odd as surely if a bubble comes through the inboard cavity on the way to the linking pipe during the outboard bleed it may decide to head upward toward the inboard nipple, just to keep the pedal nice and spongey.

 

Well, to put it starkly, if you do get a bubble passing through and popping up in the inner side while bleeding the outer - you've not done a proper job of bleeding the inner in the first-place! If the system has been bled effectively as far as the inner nipple, it's simply not possible for your mystery-bubble to appear.

 

As for Easy-bleeds - I find them indispensable - as will anyone who has to bleed the system on their own!

 

          🙆🏻 🙆🏻 🙆🏻 🙆🏻 🙆🏻

Alcester Racing

7s Ecosse™

^🙆🏻 🙆🏻 _🙆🏻 🙆🏻 ^🙆🏻

 

Alcester-Racing-Sevens.com

---

[elie boone]

Myles, i disagree with you, i always make sure that there is brake fluid comming out of both nippels before i start to bleed.

[Rattie]

If the system has been bled effectively as far as the inner nipple, it's simply not possible for your mystery-bubble to appear.

I may be missing something, but if that were the case why do they get you to bleed the most distant caliper first, working towards the nearest?

 

In the end we used an empty eezibleed to run more fluid through and I think we got a reasonably bled system. CC will check and rectify if necessary during the PBC this week.

 

I'm tempted in the future to get one of the vacuum bleeders, this overpressure with fluid or having to keep topping up without bug the heck out of me.

 

Martyn

^{_{R300GRR SV nearly there!!}}