i'm sure the brakes should be better than this

Post by **cliff** » Sun Jun 18, 2006 7:06 pm

I've changed the shoes and the mc, adjusted and bled, but i'm sure the brakes could be better.
The pedal travels three-quarters of an inch using light finger pressure then the pressure starts - this is normal i believe.
Trouble is the pressure doesn't really begin to increase and work the brakes until i've travelled maybe another two inches.
For normal driving i can cope but when you need the extra (normal) braking it can get a bit hairy.
I have to pump the pedal once to build up an initial pressure.
The pedal doesn't keep going down once i'm braking though.
I took a minor on a driving test once and did an emergency stop and the examiner slid forward (no seatbelts) and nearly hit the screen - these brakes are nothing like those!
Any ideas?

Post by **HarryMango** » Sun Jun 18, 2006 7:18 pm

cliff wrote:I have to pump the pedal once to build up an initial pressure.
The pedal doesn't keep going down once i'm braking though.

You need to re-bleed as this is classic symptom of air in the system.

Rog

Post by **cliff** » Sun Jun 18, 2006 7:45 pm

i re-bled yesterday after a few miles use, marginally better but i also managed to adjust the shoes slightly more so this may explain the improvement, do u think i should re re-bleed?

Post by **HarryMango** » Sun Jun 18, 2006 8:37 pm

Yes - air is the only reason to have to press the pedal down twice; because the first stroke pushes the air bubble down the pipe & the second one does the job - then in time the air travels back down the pipe again. It can be a real pain to bleed the brakes properly as the air bubbles seem to go & hide then reappear - see many previous posts an this matter.

Rog

Post by **minor_hickup** » Sun Jun 18, 2006 9:13 pm

If you've replaced the shoes, they will give a spongy pedal until they're bedded in. But not usually too bad.

Good luck with bleeding......it can be a real pain.

Post by **bmcecosse** » Mon Jun 19, 2006 1:29 pm

Long travel is down to brake adjustment. Did you put the shoes on right way round ? Modern shoe friction material is not as good as the old asbestos stuff - may improve once they have bedded in. But are you sure all the cylinders are moving freely ?

Post by **cliff** » Mon Jun 19, 2006 9:06 pm

bmcecosse wrote:Long travel is down to brake adjustment. Did you put the shoes on right way round ? Modern shoe friction material is not as good as the old asbestos stuff - may improve once they have bedded in. But are you sure all the cylinders are moving freely ?

am i right in thinking the only adjustment possible is the cams inside the drums (one on the rear, two on the front, each side of course)?

the shoes are the right way around, they can only go one way can't they? ie the notch for the adjusters dictate this.

the shoes on the front were equally worn suggesting to me that te cylinders are working equally, the shoes on the back only have the one cylinder so one shoe would be more worn than the other - this was the case.

i've yet to get back to bleeding - work commitments - but it's the next job.

thanks for the replies.

Post by **Willie** » Mon Jun 19, 2006 9:15 pm

Yes, the rear brakes have only one wheel cylinder so one shoe usually wears
more than the other but the wheel cylinder should be free to move up and
down in its mounting so,if it is not as free as it should be the wear will be much more one sided. If when you press the pedal it moves too far down but feels solid and then moves less far down if you pump then the shoes are
too far from the drums. If you have air in the system it will never feel solid.
Air is compressible, brake fluid is not.

Post by **bmcecosse** » Mon Jun 19, 2006 10:54 pm

The brakes should be solid - have very little travel after initial free play - and they must lock all 4 wheels on dry tarmac at 40 mph.

Post by **dunketh** » Thu Jun 22, 2006 1:26 pm

Could it be a shot master cylinder?

If your needing to pump the pedal and its getting progressively better I'd guess theres an air leak in there somewhere.

As for the travel, my pedal goes 3/4 of the way down before engaging the brakes - and I keep them all adjusted. After that point though they work fine. Harder you push the quicker you stop and all that.

Post by **bmcecosse** » Thu Jun 22, 2006 5:50 pm

That's a scarey amount of travel on the pedal !! It would fail MOT.

Post by **chrisd87** » Thu Jun 22, 2006 5:55 pm

But in the 'general discussion' board he says it's just passed...

That does sound like a bit much - 1/3 - 1/2 is acceptable perhaps, but 3/4 must feel fairly dodgy!

Post by **bmcecosse** » Thu Jun 22, 2006 6:12 pm

Unless he means 3/4 of an inch ?? Which - still not ideal - is not quite so bad.

Post by **d_harris** » Thu Jun 22, 2006 6:14 pm

Depends what you are used to I guess

Post by **dunketh** » Fri Jun 23, 2006 12:15 pm

In thinking, thats an exageration.

Sorry.

But there is a fair bit of travel before the brakes really 'grab'.

For MOT purposes the foot brakes were 70% (pass is 50!) and the rears about 28% (pass is 25 iirc)

I'm not sure what scale this is done on, I know it nearly jumped off the rollers when he stood on the brakes though!

Post by **Welung666** » Fri Jun 23, 2006 12:27 pm

dunketh wrote:I'm not sure what scale this is done on

I's worked out on the kerbside weight of the car, IE. the percentage of the vehicle weight compared to the stopping force.

Lee

Post by **bmcecosse** » Fri Jun 23, 2006 1:59 pm

And the MOT station will have no data for the kerbside weight of the car - so they may have to use Tapley meter instead!

Post by **Welung666** » Fri Jun 23, 2006 2:32 pm

My local MOT place guessed Phoebe's weight as 850kg

Lee

Post by **dunketh** » Mon Jun 26, 2006 12:48 pm

The MOT station's weight charts started in 1970 so they did have a Morris 1000 on there, weighing in at 960 Kilos iirc.

Not as heavy as I'd thought considering the agriculural 'tough' construction of a Minor.

Morris Minor Owners Club

i'm sure the brakes should be better than this

i'm sure the brakes should be better than this

Re: i'm sure the brakes should be better than this

brakes