Brakes have been good so far, but went to Bug Jam last week, all fine getting there, but on the way back the brake pedal seems to be travelling a coule of inches down before the brakes start to work properly - they stop the bus fine once the pedal has gone down that few inches. Could it just be air in the brake lines? I did bleed them on the left side a few weeks ago when I had to take the left hand caliper off to do the wheel bearing - must admit I didn't bleed the other side. Or could it be a leak developed in the servo pipe? thanks
Pump the pedal a few times with the engine off...if the amount of pedal travel reduces then you have air in the system. A leak in the vacuum side will have a noticeable effect on the engine at tickover ie cause an over lean mixture.
Another poss is that the rear brakes aren't adjusted properly - part of the pedal travel is "wasted" bringing the rear shoes up to the drums.
I second snotty above. After refurbishing my brakes and bleeding the system , i got very frustrated that i could not get a "good pedal" . I then spent an age adjusting the hadbrake cable so the brakes were just off with the handbrake off. Then presto a reat brake. The adjustment was very fine , i found a half turn on each side of the handbrake cable made a difference . Be patient and you will get there
Servo not working would have the opposite effect - the pedal is harder and not softer. Likely you've got air in the system and worth bleeding through everything.
Bring the shoes (nearly) up to the drum first with the star adjusters, then take the slack out of the cable
As Snotty says, you should adjust the shoes with the cables slack, then adjust the handbrake which should never need adjusting again unless you replace the cables. When you notice you have to pull your handbrake on a long way, it's time to adjust the shoes again, not the handbrake cables.
I've just had mine done at a garage. I was going to replace the rear wheel cylinders myself but then I was 2busy and 2hot! Anyway....... After adjustment, new brake fluid and bleeding they are the best they have ever been. Money well spent. Glad I let someone who knew what they were doing do it now!
Proof indeed that Bays, contrary to the popular view, have excellent brakes . Given that they were churned out in their millions and so sold to hard-nosed fleet managers, how could that not be true? PS They have pretty good steering as well. And not a bad gearshift. And nice, stable (if somewhat bouncy) suspension.
thanks guys - will look at the rear adjusters as I have never inspected these. Seems to get worse when you are revving the engine more, so perhaps an air leak? Can you buy the hose which runs from the servo to the manifold?
Worth stripping and fixing your rear brakes anyway, fella. They tend to get neglected and are normally in a right state. Any lack of adjustment will cause a long travel brake pedal (although that may not be your prob).
My guess would be the rear wheel cylinders are probably leaking. Only took me a couple a minutes to take the wheels and drums off to have a look. But then I took it to a garage to get the work done. Mine hadn't been apart for about 4years! Tut tut!
4 years!? I'm sure there are folk out there that haven't had their rear brakes done for 20 years: they're just a mass of manky brake dust and leaking fluid. As you say, changing the rear cylinders always worth doing.
You say worse, but what do you mean exactly? The brakes not so good? More pedal travel? Servo test for MOT is this: Engine off, pump brakes several times then keep the pressure on the pedal while you start the engine. The brake pedal should sink an inch or more. If your engine barely splutters into life you might have to give it a little blip to get the effect. From your first post it almost sounds like your servo started working! Too much free play then good pedal is adjustment. Spongy pedal is air in the system. Both is both.
I've just been through the same process and tried to adjust/bleed the brakes and still having trouble. The pedal goes halfway down on the first press but pumps up ok so I re-bled using the 2 man method and all the fluid is brand new... but still the same. It's strange sometimes it feels fine without too much travel, sometimes goes down an alarming way before any effect! The handbrake takes 8-9 clicks now, and the wheels do not bind but feel a little stiff to turn... and i can hear a little scraping now when driving along, especially when cornering... but my question is how do you gauge what people mean by rotating free or binding when adjusting the wheels? I have read a few different descriptions about how to adjust the shoes saying adjust till they bind then slacken off 3-4 clicks till they spin freely. With mine though, 3-4 clicks mean it is still fairly stiff to turn, they will spin maybe 1 full revolution with the wheel on then that is it. I realise it's all down to experience and a little experimentation but it would be good to know what the norm is.
It's not unknown for a sticking dust seal on a caliber piston to drag said piston back in resulting in more pedal movement being required to push this piston back out before getting 'feel' in the pedal. If all your adjustments etc are correct might be worth cleaning out you calipers.
You have to do the star adjusters easily on each wheel. You adjust them up until they are binding, them you back them off, evenly, until they aren't. I guess you've had the hubs off to see whether there is actually any brake material still there to adjust? As above, don't mess with the handbrake cable, and when the brakes are properly adjusted the handbrake should pull out 5 clicks.
Do you have on your bus , pedal pivot shaft a humungous return spring ?(as mine does, was broken on inspection)may be worth a look?
Should have added the whole brake system (pads, discs, calipers, shoes, drums cylinders, adjusters, brake fluid) has all just been replaced! What I'm really interested to know if what people define as binding and free play. Does spinning the rear wheel and it only moving one turn-ish before stopping indicate the adjustment is too tight/loose or just right? If the adjustment is right and the brakes bled and with new fluid and everything else is new I suppose I'd have to start looking towards the master cylinder...
It probably shows that it is too tight or uneven. You need to adjust them so that the brakes are opens fully into the drum and them back them off evenly. Just realised I'm not replying to the original poster!!
