Clutch slave cylinder symptoms / diagnostic

[Timelourd]

Can someone help me confirm that my clutch slave cylinder is my issue before I go taking out the transmission in my transit connect tdci?

-Won't get into gear when engine is on, but will when it's off.

-Clutch pedal travels to floor without resistance (springs back only because transit connects have a spring attached to the pedal itself, otherwise it would stay depressed). Action is not spongy or irregular, just loose.

-Bleeding the clutch system results in fluid being pulled through the master cylinder, but then it spurts out tons of air. Eventually it runs clean but the pedal stays completely free/loose

-i replaced the master cylinder, and the problem persists.

It's a lot of work pulling the whole transmission off just to change a friggin slave cylinder, so i'd like more certainty before starting that.

Thanks.

[Boghopper]

That's what your symtoms sound like to me, most definitely. How many miles has yours done? How is your van coping with reverse gear?

[andz327]

If slave is fooked you'll be losing fluid, if you get air out then clear fluid and still no pressure, then recheck bleeding and air in it more than likely is the master cylinder if bled and no air when rechecked it could be pressure plate collapsed...but should here not good noises from clutch
But reading you post you keep getting air it sounds master cylinder......... when you changed master cylinder did the seal on end of pipe come out OK. If anything like the transit mk7 there's a special seal not an O-ring think ford call it a plug or something like that and you would be drawing air from pipe fitment area but would imagine you'd see a leak of some sort unless you've got fluid everywhere from messing about with it
If your pipe looked like this when
You took it out the seal is missing , usually stuck on old master cylinder if you don't know its there
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[andz327]

What's the latest.....seal still in old master cylinder???

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[Timelourd]

What's the latest.....seal still in old master cylinder???

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Hey Andy, thanks for replying. I had gotten a bit into it before I remembered I had asked about it.

I've actually taken off the transmission... because I didn't check back here first! Pretty dumb. But anyway, I can post pics of the inside of the clutch to confirm that it probably isn't the slave...

I should have come and checked... but in a weird way, I was enjoying myself too much. I've never taken a transmission off before.

I'll go back out and check the little rubber thing that could possible have saved me 4 days work, if I'd looked here before resuming work.

[Timelourd]

That's what your symtoms sound like to me, most definitely. How many miles has yours done? How is your van coping with reverse gear?

Hey Boghopper - thanks. I think somewhere over 155k (a fair bit) Reverse has been just fine and dandy until this happened.

[Timelourd]

So, now the question is, with that slave cylinder looking all new and fine as it is, and considering I'd have to re-apply the Loctite 518 to seal the cylinder, should I take it off to see if there is a problem underneath, or just leave it on, and put it all back together again?

[Timelourd]

UPDATE: The little rubber buggers appear to be in tact. Maybe I didn't take the transmission off for nothing after all...

Also the inside of the transmission is black as sin. Is that... normal?

[metalworker0]

UPDATE: The little rubber buggers appear to be in tact. Maybe I didn't take the transmission off for nothing after all...

Also the inside of the transmission is black as sin. Is that... normal?

could be needing the loctite ..the oil may be out of the gearbox where the loctite should be ..or it may be a leaking crank seal

if its a leaking crank seal you'll see oil on the back of the flywheel

all the best.mark

[Boghopper]

I'll just say that I have known, mainly master cylinders, become useless but not actually leak any fluid. I do not know the exact working of the internals of the clutch slave on these vans, but if it has seals within it to create hydraulic pressure they can not do their job of maintaining pressure, but at the same time, not actually leak fluid externally. If, as I understand it, you have your gearbox off now, I would suggest changing the slave not only so you don't have to go through it again, in the near future, but to eliminate it from the equation.

[andz327]

UPDATE: The little rubber buggers appear to be in tact. Maybe I didn't take the transmission off for nothing after all...

Also the inside of the transmission is black as sin. Is that... normal?

They're O-rings that's not what goes on them

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[andz327]

If the orange o-ringed end is into master cylinder it will seem like faulty master , probably why you still had problem after changing master cylinder
At least try it before spending more money
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[Timelourd]

If the orange o-ringed end is into master cylinder it will seem like faulty master , probably why you still had problem after changing master cylinder
At least try it before spending more money
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Can you explain more about what you're suggesting I do? I have checked the seals on the fluid hoses and they're fine. What orange o-ringed end? Do you mean the rusty one with the purple o ring in my pic?

[Timelourd]

I'll just say that I have known, mainly master cylinders, become useless but not actually leak any fluid. I do not know the exact working of the internals of the clutch slave on these vans, but if it has seals within it to create hydraulic pressure they can not do their job of maintaining pressure, but at the same time, not actually leak fluid externally. If, as I understand it, you have your gearbox off now, I would suggest changing the slave not only so you don't have to go through it again, in the near future, but to eliminate it from the equation.

That is sound logic.

[metalworker0]

inside the bell housing would normally have dry black coating after so long ...yours is very wet ..so there is something wrong! ..slave cylinder, that loctite seal what was talked about ...or the crank seal

and if the clutch hasn't been changed in 25,000 ..a new one should be going in .

so change the lot .


all the best.mark