Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: marcus on 22 October 2009, 23:47:26

Title: poor brakes
Post by: marcus on 22 October 2009, 23:47:26

Hi
car (2.0 GLS 98) was stood for about a year and when I took it to be tested the brakes were very very spongy so called off the test. Anyway I bled the brake system and the brakes seemed better, if still a little spongy but passed the MOT test ok.
now done a couple of hundred miles and the brakes still do not seem right. There is a fair bit of play on the pedal initially and then the pedal seems quite heavy to depress and is spongy. My guess is that this is to do with the servo, but not sure.
I will bleed the brakes again tomorrow and have a look about - can some of the experts on here diagnose my problem
from the description I have given?

Title: Re: poor brakes
Post by: RobG on 23 October 2009, 00:10:15

You might have inverted the seal in the brake servo. Get someone to hold brake pedal down then give the servo a whack with a rubber mallet :y

Title: Re: poor brakes
Post by: marcus on 23 October 2009, 00:32:56

thanks for that idea will try it tomorrow

Title: Re: poor brakes
Post by: Jimbob on 23 October 2009, 07:13:50

could also be air in the abs unit....

you need a diag computer that can activate the pump while you bleed to fix that.

Title: Re: poor brakes
Post by: rustym95 on 23 October 2009, 07:22:29

check the disk size, if there is 0.8mm ring in the disks( or deep rigges) they are nearly finished, would pass mot, but if rings get bigger they need to be replaced, rear disks dont get alot of pressure on them when braking, but would change the front disks, dont help disks if they have been stud for a long time they wear down quicker when they are used again, unless they are cleand before use again.

Title: Re: poor brakes
Post by: Kevin Wood on 23 October 2009, 09:54:39

I would start by bleeding all the old fluid out to be replaced by fresh. It will have absorbed water while standing and that could be your problem. While you're there check each caliper for leaks and make sure any flexible hoses are sound and not bulging.

Have a look at the state of the friction materials as well. If the disks corroded whilst laid-up they might now be pitted leading to poor friction. If it doesn't improve with a few miles it may be worth considering fitting new disks and/or pads depending on condition.

Kevin

Title: Re: poor brakes
Post by: ENFIELD_MV6 on 23 October 2009, 11:27:37

remember when bleeding the brakes to start with the caliper furthest away from the servo/resevoir, also check for air leaks at the servo and the pipes to it, is it a estate or saloon ??? not sure about the omega but most estates have a brake bias valve on the rear beam for when they are fully laden might also be worth checking there to see if there is a bleed nipple ( monterey/trooper lwb have also volvo estates do)

Title: Re: poor brakes
Post by: marcus on 23 October 2009, 14:25:15

thanks chaps - lots of ideas to check out! 

Title: Re: poor brakes
Post by: mathewst on 23 October 2009, 15:47:36

As Kevin said the brake fluid absorbs water and moisture over time and can boil if brakes used to frequently over short period of time (traffic jam) so change it as soon as possible. This can also make the brakes feel songy as the fluid looses pressure a little.

Title: Re: poor brakes
Post by: marcus on 23 October 2009, 19:53:02

bled the brakes (again) and although the pedal only feels a bit less spongy the brakes are really sharp now, what a difference. I am surprised that a bit of air in the system seems to result in very little servo brake assistance. I suppose the lower pressure with air in the system is reflected in the servo not really kicking in. Anyway a good result - many thanks.

Title: Re: poor brakes
Post by: Ghost on 23 October 2009, 21:59:49

I agree with the others, Change the brake fluid, normal is every two years,