Astra brakes

[oldtimer]

I have just changed my front pads on my 1998 astra (old shape)
everthing went well. I pumped the brakes and that was ok but when I started the engine the brake peddle fell to the floor.

I tried to pump them but to no avail.

Can anybody help. I have had astras for years and have changed the pads before but I have not had this problem

 

[keyplayer]

I think you should check all the slave cylinders are not leaking first, if ok bleed the brakes and if that doesn't sort it you may need a new master cylinder.

 

[david and julie]

Were your brakes working OK before you changed the disc pads or did you change them hoping to solve an existing problem?

I would check the discs for wear or run out, if you imagine the disc to be say an inch across when new, the part where the pads rub may now only be say 3/4" because of wear, if you fitted new pads, they may be touching the original unworn bit of the disc, this would cause the problem you describe. Have a look a the condition of the old pads, have they got heavy grooves or worn at an angle?

It could also be a sticking caliper but this is less likely.

Brake discs are not as dear as you would think from a motor factors rather than a main dealer.

 

[pipme]

Parts :- Good idea to always check main dealer first.

My Jap' car is a case in point ... ABS, discs all round ... front disc replacements ... Checked the net, found the parts ref to my car by date range of manf (from two different part makers).
Whoa! thankfully they have dwgs too, took the sizes checked my old discs O/D (overall diameter) different by a significant amount !! Other dimensions from vented disc centre line to hub assembly location face, also different.
Main dealer provides the correct component all dimensions match up to old ... wait for it, Price ? THE SAME !! Hence no contest.
Am not saying this is generally the case but be wary !!

If your brakes do not work properly, and it is not readily apparent why not ... fluid leaks damaged parts etc ... do seek professional help.
P

 

[nospanners]

You say the problem only materalised when you changed the pads.
It could be you have too much pad movement with the new pads due to deep ruts on the disk, or badly fitting pads. some pattern parts require dressing to obtain a good fit.
Do the new pads sit nicely in the calipre.
Get someone to pump the brakes whilst you look at the pads for excessive movement.