pedal travel

Post by **stevey** » Sat Sep 27, 2008 4:49 pm

hello all, just a few small things interupting my enjoyment.

the brake pedal needs excessive travel to work properly... once it bites it bites hard and straight, but it takes ages to get to that point. the master cylinder is new and starts to work as soon as the pedal begins moving, just doest bite till futher down. if that makes sense then your wiser than me.

one other thing, pulling. no not dates but to the left. if you left go of the wheel the car starts to wonder left. Its not the camber of the road as it does the same if your driving on the wrong side. the tyres are new and inflated ok, brake shoes arent that old and have been checked and adjusted correctly. Tie bar bushes are new and all other bushes look good. Theres no play in the steering rack and the shocks are ok. apart from tracking is there any other possiblilities?

thanks for reading the small novel above .......

Post by **rayofleamington** » Sat Sep 27, 2008 5:21 pm

Are the brake shoes properly adjusted? That can give long pedal travel (some brake shoes are faulty and stop the adjuster working fully - as a check, if you can't adjust until the drum is tight then the adjuster isn't working properly).

Wandering to left - if tyres all match, tracking is ok and none of the brakes are dragging, then you've got something that may be difficult to fix. Most people are confused by road camber, but as you've done both sides of the road you're already past that one!

Post by **MoggyTech** » Sat Sep 27, 2008 5:23 pm

Check length of brake pedal free play by pushing pedal with your hand, any more that 3/4 inch and you need to adjust the push rod that connects the master cylinder to the brake pedal.

Pulling to one side, possible causes

1: Brakes need adjusting so that both sets of shoes are just contacting the drums

2: Swap drums from side to side, if other side now pulls, warped/oval drum

3: Try swapping tyres/wheels from side to side. If fault follows wheel, defective tyre or balance issue.

4: File a chamfer onto leading and trailing edges of each brake shoe.

Post by **MarkyB** » Sat Sep 27, 2008 5:25 pm

If the brake push rod is adjusted with too much play (there must be some) it will feel like this.
You may be able to get an idea by moving the brake pedal with you hand.
You can feel the slight resistance when the push rod makes contact and starts pushing the piston.
If the play goes away when you pump the pedal they need more bleeding or adjustment

Tracking has to be the 1st thing to look at if the car is pulling assuming the tyre pressures are correct.
4 wheel tracking seems to be quite common now. Who knows what this might reveal.
Also a binding brake will cause the car to pull.

Post by **bmcecosse** » Sat Sep 27, 2008 6:10 pm

I would say adjust the brakes right up so they are still able to turn - but dragging - and do a road test. If pedal travel is still too long - try bleeding the brakes all round - a little air in each one will give this effect. Also - is it just 'first push' that's too long, or is it always too long ? First push of the day should move the shoes up to the drums (and can therefore be slightly long) - then the little back pressure valve in the master cylinder should hold the shoes up there and subsequent pushes should be short!
Pulling to one side - is this when rolling along, or only when braking ? If braking - then it's likely to be faulty brakes. If when rolling along - it's down to a bad tyre (swap to try another) or worn suspension bushes, one side more 'negative camber' than the other and/or more castor than the other or badly set tracking. So set the car on a nice level piece of tarmac - and have a good look at it from the front. Do the wheels appear to be equally upright - or is one leaning in/out more than the other ? Hold a flat pice of timber against each wheel in turn - pointing forwards - does it look parallel to the car centre line on each side or are they converging or diverging ? Other possibilty is faulty rear axle suspension - broken / weak spring or rotted spring mounts causing the rear axle to steer the car. Close inspection is the only way to find out i'm afraid.

Post by **stevey** » Sun Sep 28, 2008 4:01 pm

thanks for the replies
as for pedal travel when i push the pedal you can feel slight resistance when the push rod makes contact and starts pushing the piston from the start just the brakes dont bite till further down. its not just teh first push its all the time. the brakes have been bled. Will readjust brakes with a bit more drag and see.

as for the pulling, its only when your driving, not braking. The tyres arent a year old yet, balance is ok, and ive tried swopping tyres around, theres not much difference. I was hoping to have a smilpe solution without checking tracking as its only developed this since coming home from the national, and i promise i havent done any off roading or hit anything. I blame speed bumps!!!! Rear springs are ok and new bushes fitted at the back.

another suggestion is to use a gallon of petrol and a match, but i think ill wait and tinker.

will keep you all posted

thanks

stephen

Post by **bmcecosse** » Sun Sep 28, 2008 4:04 pm

I'm sure it's not that bad !! Close inspection of front suspension mounting points and rubbers required. It'easy enough to make your own tracking gauge from something like dexion angle. But the simple check with a length of timber will tell you if there is anything seriously wrong.

Post by **MarkyB** » Sun Sep 28, 2008 5:57 pm

Does having the hand brake on make a difference?
It should have the effect of "adjusting" the rear brakes to no gap at all.
It is probably worth checking the tracking yourself or make sure the place that adjusts it does it right which means 3/32 toe in or 2.5mm NOT 0% which seems to be what most places do if they don't have the right figures or can't be bothered.

Post by **stevey** » Mon Sep 29, 2008 11:07 am

no its not that bad the sun is shining so ...... having the hand brake on doesnt make any difference. Well as long as it stops the MOT man should be happy. All front suspension bushes are fine. I think ill get the tracking done any way. then we'll see.....

thanks for the suggestions, ill keep you posted. Any way off on a run on saturday, as long as i dont sneeze while driving theres no problem!!!!!!!

Post by **rayofleamington** » Mon Sep 29, 2008 1:04 pm

New info - it developed fairly suddenly

This rules out some of the possibilities.

Sorry to question your inspection ability... but possible causes can be damaged rear spring / eyebolt pulling through, cracked front chassis leg, failed rear spring mount etc... (anything that can cause wheels not to be exactly where they should be).

Post by **stevey** » Tue Sep 30, 2008 6:27 pm

chassis legs are good (ask anyone out of the NI branch and theyll tell you that if its rotten or soft ill find it!!!!) springs are ok, jacked car up and put all the axel stands and jacks under the car i could find then pulled at everything, rear springs, front suspension everything. It all looks OK. Still it doesnt stop me using it its more annoying not knowing what it is.

Post by **stevey** » Mon Oct 20, 2008 1:27 pm

right final report, discovered the other day that the front wheel cyinders had leaked all over the place, two new cyclinders and shoes later the car travels in a straight line, so must have been brake related eventhough everyone had checked the adjustment!!!! so fixed(touch wood) for now. pedal trave is still a bit long after bleeding and all, but ill get use to it. thanks for the input.....

Post by **bmcecosse** » Mon Oct 20, 2008 2:00 pm

Hmmm - so the brakes must have been dragging while you were going along - is that the theory? Anyway - fixed now - so all is well! Put the matches away for now.

Post by **stevey** » Thu Oct 23, 2008 11:26 am

yes matches away thanks for all the help, just passed MOT so im happy only 8% difference in the front brakes and 12 at the back, so anothers motoring. Now once we get national dates ill be set to go!!!!

Post by **bmcecosse** » Thu Oct 23, 2008 2:06 pm

Good news! But don't put up with that long pedal travel - nip the brakes up till they are just slightly rubbing.

Post by **stevey** » Fri Oct 24, 2008 11:19 am

yep will do!!!