Clutch slave cylinder query

JamesL · Post by **JamesL** » Sat Oct 19, 2013 6:22 pm

The 1150GS lost all its clutch fluid last week and once again I had to be recovered home...

So I've just spent a happy hour with my head up it's @rse extracting the clutch actuator, and bits of bike scattered round the shed all for three hex bolts... Seriously, who designs these things?

I initially suspected the main clutch hose from the handlebar to the actuator as it's horribly corroded at the actuator end, but when I took off the actuator itself a whole lot of filthy old clutch fluid came out of the actuator housing. Is this normal or is the actuator leaking inside the housing? (PS I could easily connect it all back up to the clutch lever and test it I suppose.)

I can hardly wait for the entertainment of trying to fit it back again...

Cheers all,

James

dave the german · Post by **dave the german** » Sat Oct 19, 2013 6:34 pm

Sell tickets - you might make enough to pay for a mechanic to do it - just a thought

JamesL · Post by **JamesL** » Sat Oct 19, 2013 7:27 pm

dave the german wrote:Sell tickets - you might make enough to pay for a mechanic to do it - just a thought

Now there's a thought... There must be some way to commercialise this!

Stupid thing is, it would just be spannering if they'd designed it properly...

fatnfast · Post by **fatnfast** » Sat Oct 19, 2013 10:43 pm

How strange is that, Ive just taken mine off and put it back on tonight to replace a weeping banjo crush washer!
Yes, its a pig of a job. Any fluid/gunge on the slave cylinder (actuator) is not good. You cant really repair them and a replacement is the only answer. Not cheap, around £80 IIRC.
Whilst its apart, check/clean out the tunnel where it mounts and make sure its not the rear gearbox seal that sits behind it weeping. You can easily tell by the smell of gearbox oil. The seal has, I think, been upgraded to a brown coloured one (was black).
Its worth replacing the hose if its corroded with the stainless type as used on the adventure model.
Putting it back together is just as much fun as well. Ball end allen for the mounting bolts helps and you will need to apply pressure to the slave when fitting it. Attach the hoses to the slave before refitting, torque is 9Nm and dont forget new crush washers (halfords do copper ones or pennies from bmw) and gasket. I cut a little nick out of the bottom of the gasket so any future leaks are spotted early.
Good job you looked though, eventually the leaking fluids will make their way down the pushrod to your clutch, and changing that is not cheap or fun.
Good luck!

R-man · Post by **R-man** » Sun Oct 20, 2013 11:56 am

Yes its a rotten location-by-design, but having been there (twice) I agree with Fatnfast that its a good thing to look into.
Like 'CJ' (-remember the Fall and Rise of Reggie Perrin?) I didn't get where I am today without checking the colour of my clutch fluid, to catch this deterioration before 'the next time'...

Anyhow, now you've done that, enjoy having an improved clucth action/feel, and that you shouldn't have to go in there again soon.
p.s. useful tip from fellow Trixters is after refill with new fliuid to tap the fittings along the clutch line (where tiny air bubbles cling) and use a heavy elastic band to hold the clutch lever back to the bar overnight, so they get a chance to rise to the master cylinder. Worked for me!

JamesL · Post by **JamesL** » Sun Oct 20, 2013 2:54 pm

Many thanks all, tested it off the bike this morning and the slave cylinder is toast. Thankfully the gearbox seal seems to be ok - slight smell of hypoid, but the stuff that's come out is odourless manky clutch fluid.

I've taken advantage of the strip down to clean and ACF50 all the bits that you normally can't get to, including an attempt to get to the earth connection on top of the engine. I should have known really but although it's only four nuts to remove the battery tray (non ABS model) they've hardwired a load of cables to the underneath of the thing, so you can't actually remove it, and the earth bolt is locked solid...

So, roll on next weekend for Clutch Slave Redux!

James

JamesL · Post by **JamesL** » Fri Nov 15, 2013 8:39 pm

FWIW I thought I'd feed back:

Actually it all went back fine - technically straightforward, just a complete pain.
Agree worth replacing the main hose with the stainless upgrade, easier to thread through too.
Also, sourcing a second hand hose seems straightfoward, except that BMW seem to have a unique hose for every model. Gave up after two and bought OEM stainless above.
Actually I think you can buy perfectly good 3rd party hoses, should have thought of that.
Worth taking care over rerouting / refittingthe main hose as it may foul the cables to the LH injector
My choke / fast idle is now a bit stiff, I think due to the above. No I'm not going to strip it all out and adjust!
When you bleed the clutch, just unscrew the fast fill adapter, discard and replace with a bleed nipple. Wasted at least an hour trying to get the hex bolt out before I twigged.
Torqued up the actuator mounting bolts with a 1/4" socket & extension, and a sawn-off 5mm hex key. (I now have a collection...)
On road test clutch was slipping a bit, so took Advrider's advice and fired 400ml of brake cleaner into the flywheel / clutch assembly via the timing cover. Sorted.

Anyway, now runs fine! (Thinks, kiss of death probs...)