Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: kingers on 17 May 2010, 22:45:33
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Righto, picked up a '98 2litre petrol CD, nice original motor but the brakes are chronic compared to my other '97 2 litre petrol.
They are spongy and the pedal is long. It will stop hard if you bury it the whole way down but something clearly isn't right. To date I have done the following -
- Checked pads and disks, bit of a lip on the front disks but nothing shocking, all others ok.
- Checked pistons were moving ok
- Checked pads weren't welded to the callipers
- Checked sliders and greased where necessary
- Changed the brake fluid
- Checked the master cylinder by holding the pedal hard - it doesn't gradually move further
Still as spongy as fook.
Any likely cause lads? Servo? Seals reversing?
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Have you bled the brakes.
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lol, sorry meant to say they were bled when i changed the fluid.
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I changed my fluid but there was a bit of air in there somewhere and I had to keep bleeding the rears until it came out - much better now!
Might be worth bleeding through again......
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An Easybleed makes the job so easy for the money ;)
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my v6 was the same when I got it(had been stood a while),new pads all round and a fluid change sorted mine
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have you tried adjusting the pedal height ?
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Really bled them thoroughly - went through 1.5litres.
If no plausable cause comes up i'm tempted to replace pads and disks on the front ... but i don't think it's the cause.
Pedal height - the pedal sits in the normal position (when compared to the other car). Do you meant to make this higher? Or change the point at which the brakes bite?
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still looking into this problem - the pedal feels kind of hard and only bites when pushed hard - it's like it's only getting limited servo assistance .....
Anyone got any pointers on typical problems with the power assistance or where to begin looking?
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if your happy with the rest of the braking system, may be a look at the brake servo especially as you say the pedal is now firm. pump the pedal to deplete the (vacuum if its there) pull the vac pipe off and start the engine.the pipe should suck like a good en. refit the pipe and if working the pedal should have assistance.
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Cheers, the vacuum pipe is which one? The pipe going directly onto the front of the servo?
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yep,push fit.
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Had a pull at the fitting that goes directly onto the servo (it has a flexi rubber around it) but it won't budge easily - i'm afraid of damaging it - have i the right one?
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have you tried adjusting the pedal height ?
Tell us more re this mate :y
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have you tried adjusting the pedal height ?
Tell us more re this mate :y
OK. I've put this in the plainest way I can, but have still probably tripped over my words.....
On Omega B, there's an ability to set the brake pedal height, which of course also takes slack out iof the brake pedal.
what you're achieving :-
I use this feature to set the pedal height exactly to my taste, but more importantly to remove slack from the system - the annoying first inch or so of travel that does nothing.
how to do this :-
first, remove the brake lamp switch. I'm sure there's a "how to" on this, but it involves releasing the setting clamp (red plastic) and releasing the switch from its bracket. we'll come back to this later.
next, on to the pedal itself. While you're down the footwell, press the pedal a few times by hand to exhaust the vacuum reservoir in the servo and then notice the amount of slack that you have before the pedal goes hard, this is usually at least an inch, or maybe more. The actuation rod from the pedal that disappears through the bulkhead into the servo has an adjustment point - actually, the end is threaded where it goes into the brake pedal clevis, with a locking nut fitted ( 14, 15 or 16mm A/F ). It is this adjustment that you can use to remove the slack. slacken the locknut and extend the length of the operating rod by screwing it into the bulkhead, self-tightening pliers are the tool of choice. Keep lengthening until you're happy that you've removed all of the slack. Be warned, however, that you must stop before you run out of clevis to hold the end of the thread.
third, re-fit the brake lamp switch. This is a two-stage proccess involving the fitting of the actual switch and then setting it's height. On Omega B, the pedal end-stop is controlled by this switch. You have two choices here, either adjust the switch to match your new pedal position or lower the pedal position a bit and adjust the switch to match...... usually, having taken out all of the slack usually results in a pedal position which is too high to be of comfort to most, so de-adjusting the actuation rod will lower the pedal again, but you must then set the brake lamp switch to prevent any new slack appearing at the top of the pedal.
setting the switch involves adjusting it's position and clipping in the red plastic locking piece again.
in any event, remember that you're adjusting the brakes - you MUST ensure that:-
the operating rod remains fully engaged with the brake pedal clevis
the locknut is fully tightened on completion.
you will be surprised just how much play you have just removed.
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on some vehicles with "remote" master cylinder and servo,(fitted to the ns of the engine bay, rhd vehicle)
wear can occur in the linkage points,(not very often)
the omega is direct acting and shouldnt require any pedal adjustment.
the diect links are preset and usually loctited. you really dont want them to come loose.
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master cylinder and servo are drivers side (right hand drive)
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There is a reference in the Haynes manual to using Tech2 to power up the ABS pump to bleed the air out of the deeper recesses of the ABS valve.
I don't know if you could achieve the same effect by driving across some wet grass or gravel and stamping on the pedal?
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the problem is servo related we reckon (garage and me). They found a loose vacumn hose and that has improved it another bit but it's still not right, he reckons the servo needs replacing but i'm going to take another look around at the pipes first....
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Update on this, I ended up replacing the front disks and pads and it did improve it somewhat. It's still not as good as my old Omega but I've gotten used to it and it does stop sharpish once you bury the foot.
The NCT (Irish MOT)showed good braking force from the brakes all round... so i'm inclined to do no more with this.