Anyone got the definitive method for bleeding brakes? Everyone I speak to tells me something different.
Some say start at the brake closest to the fluid reservoir but others say start at the furthest away? Some say open bleed screw, get someone else to pump the brake pedal until its hard then while pedal is to the floor close the bleed screw, but now been told not to do that and to only push pedal halfway and then close the bleed screw.
All very confused.
Got to bleed the correctly so that we can check if there is in fact a problem with the system or if its just that they had not been done properly in the first place.
Brakes were fine when we got the car but one brake pipe needed replacing. This was done and we attempted to bleed the brakes but by the next day the pedal was very spongy ?. first attempt so we may have just done it wrong.
Further pipe was replaced by someone else and brakes supposedly bleed again but 5 months of sitting in the garage they seem to be spongy again. It?s a 1980 Mini with drums at the rear and disks at the front.
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This is taking me back a few hundred years.
I'm no expert (one will be along in a minute) but I was always taught to put rubber tube onto valve and other end into part-full jar of fluid (unless you've got those new-fangled automatic thingies), open the valve and get someone else to pump the pedal. When it firms up, one final half-push and hold while you tighten the valve. I always started with the furthest corner. Having to repeat could be because you got some "fizzing" in the fluid and it's now un-dispersed into an air lock again.
Now bring in the experts.....
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Terry
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Mini brakes will feel spongy if the rear drums are not adjusted properly since that would allow too much travel.
Have someone else pressing the brake pedal and lock off the bleed nipple while the pedal is travelling downwards. Trying to do it when the pedal is stationery half way will usually allow a small amount of air back in.
I used to start with the furthest away since logically that would contain the most air given that it is also the longest pipe. I'm not sure its actually that important as long as you bear in mind that the first one you do will also be removing air from all the common areas of the system, not just the part unqiue to that wheel.
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Thanks for the tips, will give it a go tonight and see how I get on. Lets hope it just was not done correctly the first time around and its nothing more sinister!!
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It's also generally advised not to pump the pedal to the floor either, as this causes the master cylinder seals to see a part of the cylinder they don't normally and this can wreck them. Might be worth investing £15 in a gunson's Easi-bleed which uses air pressure from the spare tyre to pressurise the brakes and makes a much better (and easier) job of bleeding.
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RichardW
Is it illogical? It must be Citroen....
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RichardW is right- never push the pedal down into new territory, it is a sure way of wrecking the MC.
I used to use the jam jar method, holding the pedal down with a stick while I nipped round and tightened the nipple. Then I discovered the Gunsons Eezibleed.
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As someone who has just finished racing Mini's,I can concur with the above.
Start at the furthest away,and work forward.
Also,if it's a 10" wheel model, (Pre 84) it will be on drums all round,with no servo,so take up the adjusters on the back of the drums until you feel the wheel binding,and then slacken it off a gnats.(You'll need the car jacked up at each wheel to do this.)
There are little square pegs on the back of each drum,and there are 2 on each rear drum,and 1 on each of the front's,but you'll need a special spanner for the pegs,which is square also.
If you need any more info on the Classic car,then all your needs can be catered for on the site,which you can access via the link below.(You'll need to register to post etc.)
Ken.
p211.ezboard.com/bminiclassic
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Sorry.Brain fade.
There are 2 on the front,and 1 on the rear.
Ken.
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and they round off *really* easily if you are not using the correct spanner. You may also find that a bit of WD40 would be a good idea if they haven't been touched for a while.
Ditto the bleed nipples themselves.
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I too have used Gunson Easy Bleed for over 10 years. I bought it as my wife and I would always argue when I asked her to sit in the car for 45 mins while the job was done. The key to bleeding is to be aware that air gets sucked in via the nipple threads.
I usually 'blow' out the old fluid. Then I fill up, and bleed it. Then bleed a second time. Works well. After the blow through, clean the nipple threads and put a tiny tiny smear of copper grease on them, so that in the next 2 years they will not rust in. Dont overtighten, as it is so easy to do.
If you do it manually, the secret is to close the bleed nipple when the peddle is down. This stops air being sucked back in on the peddle upstrock via the nipple threads. I didn't believe this at first, but it is true.
The sequence is open nipple...
peddle down...
close nipple...
peddle up...
open nipple...
down...
and so on.
Stand the fluid upright for a day after purchase to avoid air in suspension. Never re-use fluid. Only buy dot 4, not cheaper dot 3 fluid.
Good luck.
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Gunsons EasiBleed every time. Been using one for 15 years now.
DO NOT put any grease of any sort onto the threads of the nipples. If any grease gets into the fluid in the cylinder it reacts with the brake fluid causing degradation. An alternative is to put the rubber cap back on the nipple after tightening, clean the area with meths or similar and then seal with ignition sealer.
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