Clutch master cylinder replacement

[xavier]

Hello I just used the "how to change your clutch SLAVE cylinder " information and it seems to have gone well. I cannot find an article on changing the MASTER clutch cylinder . Does anyone know where I might find one?[/code]

[daimlerman]

Do not think the wiki is that far advanced,yet.

Clutch master is bolted to the frame of the pedal box and is playful to get at.Depending on your own physical size,access can be improved by removing the driver's seat.
Empty the clutch fluid,easy way is to open the bleed nipple on the slave.
Unbolt the feed pipe from the master to the slave from the engine side of the bulkhead.
Whilst still in the engine room,slide the feed pipe off the bottom of the fluid holder.
Unbolt the pedal from the end of the master.
Unbolt the master from the pedal box and draw through into the footwell,complete with the feed pipe.

Note that the feed pipe pushes onto a connector,which in turn is pushed into the master,this connector usually breaks when one attempts to remove it so have a spare in stock just in case.
Note the exact position/angle of the connector for going back.
The last connector that I bought cost about £2,but is 'dealer only' and needed to be ordered.

Master is held to the pedal box by two cunningly hidden 8mm bolts,a three eigth 8mm socket and short extension will be needed.The throttle cable will also block access to one bolt,but with care the socket extension will hold it clear.

Not as difficult as rear beam bushes,but far more fiddly than swapping spark plugs!

[xavier]

Ta

[Grrrmachine]

If you can take some pics as you go then I can make the Wiki article for future reference

[daimlerman]

If you can take some pics as you go then I can make the Wiki article for future reference

The thing is such a swine to get to that you really need to get photo's taken by some-one who has a dashboard out,then a clever fecker like you can mark the mounting bolts....

[xavier]

I did the change today and all went well. I photographed it, but the photos were not too good when I looked at them later. Grrmachine and/or daimlerman I can send them if you want. The only thing different from your good instructions, Daimlerman was that the 2 bolts anchoring the master cylinder were 10mm not 8. The instructions, were however, very good. The gear selection is now a little bit better, but still not great. The shuddering on take off is gone though. The slave cylinder was knackered. It was letting fluid past the seal. Now with the slave and master cylinders changed, does anyone have any suggestions on why 2nd and 4th are still hard to engage.

[daimlerman]

Sorry,I was working from a failing memory!
Let the grrmachine have look at your photo's,he will know if he can do anything with them.

Only thing that springs to mind regarding 2 and 4 could be wear in the gear linkage bushings,there's a knuckle joint on top of the 'box that is a known wear point,if you have a look in the wiki at 'short shift conversion' you will see what is involved in getting at the linkage.
Generally speaking,the gearboxes are very strong and failure is almost unheard of in normal usage.

[daimlerman]

Grrrmachine;
This is the only pedalbox photo I have,taken more to show the difference between LHD and proper side drive.

[capnmchl]

Hint

If you use 1/4" drive tools, the job becomes that bit easier.

I'd have to agree with possible wear in the gear linkage for 2 and 4, as they're the only gears that require the rod to move forward.

[xavier]

Thanks guys. Sorry to sound dim, but how do I send the photos to grrmachine?

[Grrrmachine]

I sent you a PM with my email address yesterday. Check your Private Message inbox (top right corner of the forum)

[xavier]

Is replacing the worn bushings in the gear stick of similar difficulty to replacing the clutch slave and master cylinder?

[Grrrmachine]

I'd say it's harder. It's not more complex, but you're laying under the car groping in the dark trying to use the tips of your fingers to get things done. And the gear selector rod is often very reluctant to come out of the bushing.

But if you read the guides it just says "prise out clip A, pull off bushing, fit new bushing, replace clip"

[DHFiS]

Note that the feed pipe pushes onto a connector,which in turn is pushed into the master,this connector usually breaks when one attempts to remove it so have a spare in stock just in case.
Note the exact position/angle of the connector for going back.
The last connector that I bought cost about £2,but is 'dealer only' and needed to be ordered.

Is the the connector part 7 in this diagram?

http://bmwfans.info/parts/catalog/E30/2 ... h_control/

[daimlerman]

Note that the feed pipe pushes onto a connector,which in turn is pushed into the master,this connector usually breaks when one attempts to remove it so have a spare in stock just in case.
Note the exact position/angle of the connector for going back.
The last connector that I bought cost about £2,but is 'dealer only' and needed to be ordered.

Is the the connector part 7 in this diagram?

http://bmwfans.info/parts/catalog/E30/2 ... h_control/

That's the little blighter!

[xavier]

Will getting one of those little mirrors on a stick help replace the bushings?

[cjdonny]

Did mine 2day
Slave cylinder was a lot easier!
Just need to bleed the system

[xavier]

to bleed the system I used one of those one person bleed pipes. It is just a bit of tubing with a non return valve on one end. The end without the non return valve goes on the bleed nipple. you slacken the nipple half a turn and pump the clutch peddle. eventially the the air and some of the fluid get squirted out of the non return valve. just remember to put something to catch he fluid under the tube. It made the job V easy as a one person job. I think you call the tube an Ezibleed.

[Brianmoooore]

The actual bleeding of air bubbles out of the fluid isn't the problem when it comes to an E30 clutch. The problem that sometimes occurs, when the system is dry, is to get any fluid to come through at all.
It usually pays to do the job twice, 24 hours apart. The initial fill and bleed tends to put millions of microscopic bubbles into the fluid, and leaving it for several hours allows these to collect together into larger bubbles that are easy to bleed out.

[xavier]

Thanks Brain for the bleed advice. I will rebleed it at the weekend.
While we are on the whole gearshift topic. I know I need to replace the busing that the ball end of the gearstick goes into, the bushes on the selector rod. Is there much more else I need to get?

[xavier]

Some sites say to remove the gear box mounts and jack the box up before changing the gearshift bushes, while others do not mention it. I take it this is to get more access to the selector rod. Does it make much of a difference?

[Brianmoooore]

Remove the gearbox mounts, and lower the back of the box down a bit, not jack it up!
Check under the bonnet as you go, to make sure you're not trapping anything or pushing the fan into the radiator.
There's very little weight supported by the gearbox mount on an E30, so a couple of wooden blocks or an axle stand will do.

[bigbird76]

Hope I am not hijacking your thread but:-

I changed my master and slave a few weeks ago and bled and all seemed ok but
then I noticed the clutch pedal drops down about 30mm whilst driving and has to be lifted by hand or foot.

I bled the system again and removed the slave and pushed the slave rod in to make sure there was no trapped air but no air came out, Anyway it is still the same. I bled the old fashioned way by pumping the pedal with a helper and I was on the bleed nipple end.

Could I have a faulty master cylinder or the only other thing I can think of is there is air trapped somewhere in the master cylinder, Anyone had this problem ?

Leigh

[xavier]

Are you losing fluid from any of the hoses or connection points? Check the level in the resevoir to see if it drops from day to day.