gadget

TD5 clutch. The secret to bleeding?

39 posts in this topic

I replaced my rear brake lines a little while ago and since then the clutch has been a bit soft.

No problem i thought, just a bit of air in the clutch line.

Just been out to try and bleed it - disaster. I've pushed a pint or so through and there are no obvious air bubbles coming out but the slightly soft pedal is now blancmange and useless.

There's obviously a knack to this, but i don't gots it.

Could some kind soul share the secret please?

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I've pushed a couple of pints through tonight and i'm still getting air out of the bleed nipple.

Something is obviously not well.

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They are an absolute pig to bleed, it's not just yours being a pain. The only time ive ever had success is with a pressure bleeder. If you haven't got one, attach a pipe to a squeezy bottle, squeeze pipe over the bleed nipple and push fluid backwards, should force any air bubbles up to the reservoir.

Good luck

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I was just about to suggest reverse bleeding as I always found it rather impossible trying to force the air almost vertically down when it wants to go up all the time, clutch bleeding is reverse bleed only operation for me these days.

Find it really helps on brakes too, just not ones with ABS.

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I have never had any trouble bleeding any vehicle I've done using a Gunson Ezzebleed. About £18 and works off air pressure from a wheel. Keeps a constant supply of fluid flowwing whilst the bleed screw is open.

I assume the master and slave cylinder are in good order?

HTH,

Griff

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I'm making the assumption that the air in the system initially came in when the reservoir was drained during the brake line change, but i cannot be 100% certain that the air isn't coming from either cylinder. I don't have any obvious leaks and it was fine before the brake line swap.

Does the ezzebleed fit the TD5 reservoir cap? I've not come across any pressure bleed system that didn't require buying an additional attachment for the TD5.

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there is a trick which used to work... lock the pedal to the floor by sticking a piece of wood or something between it and the seat and leave it so over night... if no joy with this procedure and you know that the cylinders are old you better bite the bullet and replace them both cos the fact that it's hard to bleed is due to wear in the piston body along the 'travel' of the seals...you'll see the improvement...it's a good practice to replace both cylinders even as a preventative maintainance cos putting a new one against a worn one the pressure in the system will 'kill' the seals of the old one in no time anyway...you dont want to see how it is to end up in the middle of nowhere without 'pedal'

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I'm making the assumption that the air in the system initially came in when the reservoir was drained during the brake line change, but i cannot be 100% certain that the air isn't coming from either cylinder. I don't have any obvious leaks and it was fine before the brake line swap.

Does the ezzebleed fit the TD5 reservoir cap? I've not come across any pressure bleed system that didn't require buying an additional attachment for the TD5.

It doesn't come with one to fit the TD5 unfortunately, but do a search and you come across a universal cap that you can use

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Get the front of the disco facing up a slope or on ramps. The bleed nipple on the slave on the TD5 is horizontal and points out of the front of the cylinder and so a slight downward slope can leave air residing in the slave that you cant get out. Worked fine for me when i did my system. Either that, or reverse bleed as above.

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When faced with a "tricky" bleeding situation I've used the following approach.

Bleed as well as you can.

Pump the pedal vigorously, then immediately press the pedal hard-down and wedge it there with a bit of wood between the pedal and the seat-box.

Leave overnight.

Then bleed as usual.

The way this works is that vigorous pumping agitates the air-bubbles, then wedging with the pedal down (so the systemj is under pressure) causes the bubbles to dissolve into the fluid.

Then after being left overnight you bleed-out the fluid that has the air dissolved in it.

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Thanks for the replies chaps.

Once i've got the Freelander back on the road i'll have another bash at the Discovery.

Nose lift first. Then reverse bleed and if they both fail i'll replace the cylinders.

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Bled, and reverse bled and then forward bled to check.

Air appearing in each depression of the pedal and the clutch pedal resistance is fading.

Something is obviously letting air in, but i can't see any leaks anywhere in the system.

I'm going to have to bite the bullet and replace the cylinders :(

Edit: Forgot to ask.

Any air in the system will rise up the bulkhead and get trapped in the bizarre pipework that runs to the switch on the wing and back to the master.

I've read a mention of a clutch master that has the clutch switch fitted to the body. Anyone heard of this or perhaps got a part number?

I'd ditch the air trap pipework if i could fit a master with the switch in the body.

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Just worth mentioning, that I replaced both cylinders as the pedal went very odd. It turned out that air was getting in where the pipework had chafed on the back of the engine just behind the FPR. It resulted in a small leak (initially) that wasn't easily detectable as the sound proofing soaked up the fluid. Thinking it was a hydraulic problem, I replaced the cylinders only to later find it was the pipework. That stupid bit of pipe cost more than both cylinders, but I was in a rush and away one weekend, so had to buy it rather than make a new one.

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Just worth mentioning, that I replaced both cylinders as the pedal went very odd. It turned out that air was getting in where the pipework had chafed on the back of the engine just behind the FPR.

BINGO!!

The very edge of the plastic shroud at the rear of the engine has cut a hole in the pipe.

There's a flex on one side of that pipe so i think i'll need to just chop a section out and replace it.

Next problem is how do you remove the shroud? I can get to the bolt on the passenger side easy enough but i've not managed to locate the drivers side bolt yet.

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BINGO!!

The very edge of the plastic shroud at the rear of the engine has cut a hole in the pipe.

There's a flex on one side of that pipe so i think i'll need to just chop a section out and replace it.

Next problem is how do you remove the shroud? I can get to the bolt on the passenger side easy enough but i've not managed to locate the drivers side bolt yet.

Blimey - glad i posted up! It was really hard to find that on mine so im glad i could guide someone else to it!

I dont think i removed the shroud on mine, i just secured the pipe back away from it so it wouldnt touch it any more. It was a right pain to wiggle the pipe into place but it will come out and go back in without removing anything.

That pipe section was £120 from land rover i think (had no choice as i was away from home when it broke). I kept the old bits though as it would be an easy job to splice a section of replacement pipe in there. They need to be decent fittings though - i tried it with some push fit rubbish that i had handy and it worked for about 20 minutes and then snapped!

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Blimey - glad i posted up! It was really hard to find that on mine so im glad i could guide someone else to it!

I'm glad too :)

It's been driving me potty trying to work out where the air was coming from.

I dont think i removed the shroud on mine, i just secured the pipe back away from it so it wouldnt touch it any more. It was a right pain to wiggle the pipe into place but it will come out and go back in without removing anything.

I have a cunning plan.

That daft piece of insulation is a right pain when seating the rocker cover gasket at the back of the head. Mine's been weeping for an age.

I'm also pondering trimming the plastic to allow more space above the pipes.

That pipe section was £120 from land rover i think (had no choice as i was away from home when it broke). I kept the old bits though as it would be an easy job to splice a section of replacement pipe in there. They need to be decent fittings though - i tried it with some push fit rubbish that i had handy and it worked for about 20 minutes and then snapped!

I'm thinking brass m10 couplings and some 3/16 brake pipe, though i have just sent Dave a llama an email enquiring if he thinks a braided hose would work here.

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I think i've worked out why the pipe fails in the way it does.

There are 2 pipe clips at the rear of the head that secure the pipe across the engine.

The one on the drivers side works loose with vibration and the spring force of the flexi part raises the pipe and brings it in to contact with the plastic shroud.

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I think i've worked out why the pipe fails in the way it does.There are 2 pipe clips at the rear of the head that secure the pipe across the engine.The one on the drivers side works loose with vibration and the spring force of the flexi part raises the pipe and brings it in to contact with the plastic shroud.

Yep. I think my driver side clip was broken, so I cable tied the pipe loosely away from the block. It can still move so it's not secured completely, but it won't rub anymore I hope!

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David at llama says that the braided hose would be fine for this application.

I'm struggling to see where to secure the hose at the moment. I've read that the aero industry think of braided hoses as round hacksaw blades :o so securing in a way that they don't abrade anything seems sensible.

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I'm still playing with pipe ideas. Going to have to hurry up and sort this though as the car has been parked up for such a long time now that mice are taking up residence in the engine bay :o

I scribbled down the routing of the original pipe as it drops from the flexi toward the rear of the head and it would seem that someone has stolen my diagram! (Some muppet probably left it somewhere and it blew away, didn't i? *sigh*).

Anyone got a photo showing the routing please?

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I've figured out the routing but i'm struggling to see where the drivers side clutch pipe clip ANR1351 sits.

There's no obvious hole on the rear of the head to take to clip.

Anyone?

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I wonder if it would be better to forget the original routing and to go from the master up onto the bulkhead using solid pipe (no flexy yet). Follow the bulkhead along to the other side of the engine then come off there and down to the slave. The flexy pipe could be added either as you come off of the bulkhead, or as you join the slave - it's only to take up engine movement. There are plenty of pipes running across the bulkhead that you could somehow fix your new pipe work to.

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My last attempt at an alternative solution was exactly that.

There are sufficient spare slots in the clips across the bulk head for the hard line and there's a hole already in the body mount that would accept a bracket. Try as i might though i could not find a way of routing flexi that wasn't annoyingly close to the exhaust. Even using a bracket similar to NRC7441 and coming off the clutch slave in a more vertical manner.

I'm going to splice a section of pipe in for now and deal with it when the weather is better.

I'd still like to know where the drivers side pipe clip is fixed.

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I don't think I worried about the drivers side clip when I replaced mine. I tried to fasten it all back as far as possible from the engine to stop it rubbing through again.

The pipe has to come close to the exhaust at some point really - it's a pretty silly design. I'm surprised the slave doesn't suffer more frequently given its position and the lack of a heat shield. I wonder if you can come down the wing and off of there to the slave?

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