Brake help required...

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agb32
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Brake help required...

Postby agb32 » Sat Feb 09, 2019 5:19 pm

Hi,
Can anyone give ideas?

We have Sierra front disk brakes, and I have been trying to change the brake caliper.

All went smoothly until I realised I must have ordered the wrong side, because the brake pipe entrance was pointing down rather than up.

So, I put the old one back on.

Now, the brakes are very spongy, require a lot of pumping to work, and unsafe to drive.

I'm not a technical expert, so could people give ideas about what is wrong?

During the change, I didn't see any sign of brake fluid leakage, and can't detect any now...

Thanks!

simmitc
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Re: Brake help required...

Postby simmitc » Sat Feb 09, 2019 6:08 pm

Did you bleed the brakes after refitting the caliper? It sounds as if you have got air in the system, which is normal after undertaking that sort of work.

agb32
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Re: Brake help required...

Postby agb32 » Sat Feb 09, 2019 6:36 pm

No, I haven't bled them - how do I do that? There is some sort of valve on the caliper - do I just loosen that and pump the brakes until fluid comes out?

Thanks....

(might seem obvious, but I'm just learning!)

paul 300358
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Re: Brake help required...

Postby paul 300358 » Sat Feb 09, 2019 7:02 pm

The short answer is no!! you will just draw air back into the system when the peddle comes back up. Have a look at viewtopic.php?t=55918

minijojo
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Re: Brake help required...

Postby minijojo » Sat Feb 09, 2019 7:24 pm

almost right
first a friendly advice: if you are working on your brake system be sure, you know what to do, otherwise let someone do it who knows.
Get yourself a person to assist you

Buy brake fluid (normaly used DOT4 in Morris Minors)
open the master cylinder filler cap and fill up brake fluid, leave a litte space left, do not fill to the top, close filler cap
You should start with the longest brake line.
the order should be (for right hand drive cars) back left side, back right side, front left side, front right side
attach a piece of hose on the bleed screw, put the other end into a jam glass (for example)
find the right wrench for opening the bleed screw.
let one person sit on the drivers seat. The other opens the bleed screw with the hose on it and the other end in the jam glass
Now the driver pushes down the brake pedal slowly a few times. You look for bubble-free brake fluid coming out of the hose. Keep the hose in the brake fluid in your jam glas so that no air can return into the hose
When you see no more bubbles coming out of the hose, advise the driver to keep the pedal down.
Now carefully close the bleed screw. Take off the hose.
do this on all 4 brakes
check brake fluid between work
check every bleed screw if it is close and no brake fluid is coming out. Do not over tighten the bleed screws. put back the rubber caps on the
bleed screws
fill up brake fluid, close filler cap.
dispose used brake fluid properly

agb32
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Re: Brake help required...

Postby agb32 » Sat Feb 09, 2019 7:31 pm

Thanks.

Any idea where I can get a suitable tube from? Is it sold at e.g. Halfords?

What is the proper way to dispose of the fluid? Council tip?

minijojo
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Re: Brake help required...

Postby minijojo » Sat Feb 09, 2019 7:42 pm

i use a bit of tube used for the wiper washing system

for dispose, ask in the car workshop of your trust whether they dispose it for you. i little tip could help
or go to a garbage- or recycling center

Myrtles Man
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Re: Brake help required...

Postby Myrtles Man » Sat Feb 09, 2019 7:53 pm

Or you could try this:-

https://youtu.be/ag-Q_lP0dOk

kennatt
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Re: Brake help required...

Postby kennatt » Sun Feb 10, 2019 8:01 am

friendly advice...................... the one thing you should never attempt as a first time diy, er is brakes followed by a close second......
steering ....... I strongly suggest that you find someone who has a bit more knowledge to let you help him/her to do it. Brake bleeding is normally a simple job but extremely important to get it right, as you have found.Please don't drive the car until its sorted . Its too important to do it just from a list of instructions. There will be someone near to you who will help. Once you have seen it done then you will be well equipped to have a go yourself. No offence intended here hope you don't take it. good luck.

agb32
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Re: Brake help required...

Postby agb32 » Sun Feb 10, 2019 4:59 pm

Hi all,
Thanks for all the help - all now sorted, brakes back to normal.

Actually, only the brake caliper I'd been working on needed bleeding, which makes sense really, since there was almost no fluid loss...

For future reference, what spanner size should be used for the rear drum brake bleed valves? I found 7/16AF too large, 3/8AF too small, 11mm too large, 10mm too small...

They were well rusted on, so was a bit scared about stripping the nuts (and what does one do in that case? and any tips for getting well rusted bolts undone?)

Thanks...

In case it helps anyone else, if you have front disk brakes from a Ford Sierra, if they are fitted towards the front of the wheel, rather than behind (e.g. 2 oclock, rather than 10 oclock), then you'll need to order calipers from the opposite side (i.e. order front left, if you are working on front right...).

paul 300358
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Re: Brake help required...

Postby paul 300358 » Sun Feb 10, 2019 5:43 pm

They should be 7/16 AF, if you decide to change the rear ones you need to purchase BSF ones. The standard front are 7/16 UNF. Declan Burns did a helpful drawing which he posted on a thread, with luck he will re-post it.

Found it, see viewtopic.php?f=4&t=43353&p=419930&hili ... vo#p419930


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