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donsrno1
02-02-2008, 00:36
For the past couple of weeks I've had the hybrid off the road to do some work on it. The handbrake wasn't working so I stripped down the handbrake mechanism and re-built it (which now works perfectly btw :D ) but my normal brakes aren't working now. If I press the pedal it just goes to the floor, if I press it rapidly trying to build up some resistance it does build some up but if you then leave it two seconds and press the pedal again it will just hit the floor again.

When I did the caliper a little brake fluid came out when I removed the adjusting screw in the handbrake mechanism so I'm thinking it may be an air lock and just needing bled. However, I was also wondering if it could be that it is leaking? I'm guessing not though as I must have pressed the pedal about 50 times and there was no noticable change in the brake fluid level.

So anyway, from what I have said would you think its just an air lock? And if so any tips for bleeding the brakes as I really don't want to shear the nipples off after just having the caliper in bits as that would have been a total waste.

If it is an airlock would I be able to just bleed the two rear calipers or would I have to do the whole system?

Cheers.

MAXIBOY
02-02-2008, 11:27
if it hasn,t been done very recently i would get two litres of brake fluid and bleed the whole system with brand new fluid as it,s meant to be changed every two years.
i would also buy four new nipples and a small tube of red rubber grease so that you can fit the grease the new nipples once there removed.

as for removing the old nipples that can be difficult. start with the right sized spanner and try to tweek them undone with little sharp thugs..
you will either need a friend or a pressure bleeder to bleed the brakes.

with a friend get him to pump the brake pedal 10 times then hold it to the floor immediately. while hes holding it to the floor you open and then close the bleed nipple. this is then repeated till you get clean new fluid out with no air.

also i length of clear pipe on the nipple into a jam jar stop the fluid getting every where and allows you a better view of the fluid/air etc being bleed from the system.

when doing the rear brakes try and do them with the wheels fitted and on the ground or otherwise with the axle/beam jacked up as well if you have the car jacked up as this helps the rear load compensator stay in the open position

hope this helps. anything else just ask...

donsrno1
02-02-2008, 19:52
Awesome mate, thanks for the help once again. Would it be possible to just do the rears by themselves though? Its just that I'm short on time and really need to get it MOT'd. I would plan on doing the lot when I've got time in the near future but I really need to get the car back on the road at the moment.

When doing the rears what would people say the chances are of the bleed nipples sheering off? I've hear about it happening loads of times but just wondered how likely it is in reality?

Also, I forgot to mention in the first post but when you do repeatadly press the pedal you can hear a sort of thumping noise (only way I can describe it from what you can hear inside the car) coming from the left rear of the car.

Cheers.

Lunner
02-02-2008, 20:14
Yeah you can do the rears on their own, soak the nipples in plus gas a few times a day or so before you wanna do them, might be ok, or you might not, worth getting a couple of spare nipples before you start on with them

donsrno1
02-02-2008, 20:21
Where can I get the nipples from? renault? I was hoping to do them tomorrow as its the only day I have off.

Lunner
02-02-2008, 20:30
99% of motor factors will sell nipples

donsrno1
02-02-2008, 20:36
ok, cheers. I'm guessing they are just standard sizes then?

number1
02-02-2008, 20:36
Im going to refresh my brakes before the airfield day, need to change the compensator as its weeping slightly, dreading touching the bleed nipples tho :?

donsrno1
03-02-2008, 17:51
Cheers for the help guys, bled them earlier and the nipples freed off really easily and the brakes now work a treat :D . Just got a quick question about adjusting the brake bias valve but I've made a new thread about that.