I don't have a Haynes for this car (it's not mine) but looking to bleed the clutch (it's getting hard to engage reverse and bleeding the clutch has been a kwik fix previously for the owner, they're not interested in fixing the underlying issue at all).
I traced the hydraulic pipe down to the slave cylinder and there's a plastic bleed nipple which is stopped at each end, 180 degrees apart.
He pumped the clutch 10 times and held the clutch down, i opened the bleed nipple... but nothing?! Retried a few times but no joy. Reservoir is at the max line.
I've given my pressure bleeder out on loan just now. Is there any way this can be bled without an ezibleed?
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Don't tell anyone but if i've got an awkward bleeder, i undo the bleed valve hold me finger lightly over the end to create a one way valve and get an assistant to pump away, after several pumps the tell tale pulsing usually turns up, a latex glove or preferably a Marigold should be worn for this.
ElfinSafety Disclaimer Applies....don't do this at home kids.
You should of course get an old fashioned rubber bleed pipe, one with a slit near the blocked off end, about a quid, that provides the same as the do it be feel system above, the problem being that there isn't always room to push the thing on the nipple.
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Here's how I deal with hydraulic clutches.
First, flush new fluid down to the near side front caliper.
Then, get a length of flexible pipe and join the near side front caliper bleed nipple to the clutch slave cylinder bleed nipple.
Open both bleed nipples, and then pump the brake pedal, pushing fluid backwards through the clutch.
If there are seperarate reservoirs, you need to keep an eye on the levels - if the reservoirs are common, then, the level won't change much.
On trucks, where there's no hydraulic brake system, I use an oil can which I keep for the purpose to push the fluid backwards through the clutch system.
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A most interesting method there from N-C, nay fascinating, something i'd never have thought of, reverse bleeding.
Much is made of the danger of folding back the rubber seals in a master cylinder if you force the pistons back when renewing brake pads, it's a sin i'm guilty of countless times without problem...so far.
I know there's no ABS module to worry about, but does this method of yours lead me to the conclusion that the possibility of master cylinder seal damage is so rare as to be not worth worrying about, or is the ABS unit the real danger inasmuch as it's probably a ridiculously expensive problem should it go wrong.
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Reverse bleeding the clutch!, now there is a good idea. I have to reverse bleed my hot water system if its drained, due to lack of sufficient head of water,
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The reason for using reverse bleeding is because many clutches simply don't bleed well forwards - I don't know exactly why that is, as it's a long time since I've been curious enough to strip down clutch hydraulic parts.
There are some truck clutches where you'll really struggle getting any fluid out at all forwards - I remember struggling with an Iveco clutch for a few hours before filling a new oil can with brake fluid and bleeding it backwards - bingo!
The master cylinders which were really prone to flipping the seals were Vauxhall brake master cylinders - I remember the first one we saw in the workshop, we couldn't beleive it was possible until we stripped the cylinder down.
If you built up any pressure sufficient to flip the seals using my method, I would imagine that the pipe would pop off the bleed nipple end first.
I never had any trouble with Vauxhall master cylinders myself, but, as I wasn't crazy for bonus, so, I pushed caliper pistons back without trying too hard to do it quickly - it's all done with kindness - as my father used to say when someone was making an easy job difficult!
Last edited by: Number_Cruncher on Mon 12 Sep 11 at 11:13
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>> The reason for using reverse bleeding is because many clutches simply don't bleed well forwards
>> - I don't know exactly why that is, as it's a long time since I've
>> been curious enough to strip down clutch hydraulic parts.
I've got a bit of a theory about that, humour me it's probably cobblers, but i think the same applied with the drum brakes on Series Land Rovers which were a pita to bleed through.
At the slave end of a clutch is much free movement, in normal bleeding techniques by the time you've pressed the pedal and compressed any air, all you've accomplished is to take up any free play, or just compressed the spring istr finding inside slave cyls so probably still there, which means you've got no fluid down the system.
Repeat as many times as you like and all you do is take up the free play whilst shifting no air...does that make any sense?
The Heath Robinson finger valve has worked many times, only gentle pressure needed by finger just touching is enough, ten or more quick pumps compresses the air and forces it out followed by lovely airless fluid before the sprung free play can stop it happening.
Don't suppose i've explained that too well as usual, but hopefully you get my drift, as usual probably miles away from what the root cause is.
Recalling Series LR's, you could bleed these till the cows come home and never get a pedal, but remove the drums and clamp the slave cyls with G clamps or Jubilee clips would get you bled out to a rock solid pedal in miinutes.
I think the same free play syndrome was the problem.
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Bloke I met recently knackered his Zafira master cylinder by pushing the piston back in. My method is to clamp the brake hose (using a proper hose clamp rather than a pair of mole grips which some clowns use), then open the bleed nipple with a one-way bleeder attached as the piston is pushed back. By pushing the piston back without the nipple open you could push dirt back up stream. Better to get it out of the system altogether.
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With the Zarifa rear brakes you need a wind back tool to simultaneously rotate and push the pistons back in with. Simply pushing them in will knacker the calipers.
I recently did the front brakes on my Vectra-C. Usually I would crack open the bleed nipples, but this time I didn't have anyone with me to bleed the brakes afterwards. I just carefully and slowly pushed the pistons back in. As the brake fluid is changed every 2 years on my car, it's unlikely that the system has any muck in it. The fluid in the reservoir is as clean as a whistle.
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>> As the brake fluid is changed every 2 years on my car, it's unlikely that the system has any muck in it. The fluid in the reservoir is as clean as a whistle.
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It would be.
That's the fluid that's changed...... ;-)
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Ford Fiesta - 04 1.4 Bleeding Clutch Problems - -
