Alfa Romeo Owners Club of Australia Forum

Technical => 932 Series (156, GTV, Spider, 147, GT, and 166) => Topic started by: josh18 on August 25, 2016, 10:03:58 PM

Title: Clutch slave cylinder swap?
Post by: josh18 on August 25, 2016, 10:03:58 PM
Hey all. After a good run with our new 156 JTS it seems the honeymoon is over.
The clutch went spongey today and the car refused to go into gear. After a few pumps of the clutch it came back and seemed ok for a while but before we got home it was at it again. No amount of pumping would help when i was just about home, so I reached down and pulled the pedal back up and it worked again.
So there is definitely air in the system I think, no fluid seems to have been lost.
At first I was thinking master cylinder but after doing a web research fest it seems more likely to be the slave.
This weekend I plan to bleed it and see how it goes but I can't imagine it lasting too long.
So what do you guys reckon- slave, master or something else?

Ive looked up what it takes to change it and it seems like quite a huge task to remove the box but if it's gotta be done it's gotta be done.

Cheers, any advice, hints, tips much appreciated.
Josh
Title: Re: Clutch slave cylinder swap?
Post by: alanm on August 27, 2016, 08:33:26 AM
Sorry to hear your honeymoon is over! As good as 156s are, they are getting older and components are going to wear out.

Clutch master cylinder is probably visible where it connects to the pedal under the dashboard.
If it is failing, you will see fluid leak on the part and commonly (I think) drops of fluid on the carpet. I just had this problem on my 916 GTV.

I hope this helps to narrow your search for the problem.
Al.
Title: Re: Clutch slave cylinder swap?
Post by: colcol on August 27, 2016, 10:52:50 AM
These slave cylinders in the gearbox behind the clutch are becoming common now, it sounds a PITA job to take the gearbox off to change it, but you will find your clutch is on its last legs, so throw a new clutch assembly at it when you put a new slave cylinder, and have a look at the rear crankcase seal, and put a new on in while the gearbox is out, look at any leaking gearbox seals as well.
The JTS is now 14 years old and is an older car now, and you have to expect these things, Colin.
Title: Re: Clutch slave cylinder swap?
Post by: josh18 on August 27, 2016, 07:53:34 PM
Thanks guys.
I started it today and reassuringly, there is a tell tale drip of brake fluid under the bell housing- good to know it's definitely the slave! I will get a clutch/ slave Kit and be done with it. Looks like it needs rotors to so I'll probably get them too.
So far all I have done is got most of the things out of the way of the box and am now setting about removing the front left suspension. I got stopped because I went and bought a 36mm socket for the hub but didn't realize it was a 1 3/4" drive and I don't have an adapter. So I stopped there and removed the battery and tray etc. I am learning that everything seems to be connected to everything else, but I suppose that's just modern cars for you.
Have you guys done this job yourself? Even though it will be long it all seems pretty straightforward. I am looking at making some sort of cradle for my jack to wheel out the gearbox with rather than try to heft it out. I am not sure however, how the gear shift cables detach from the box. I'm hoping that it isn't something stupid like (but kind of expecting it) they only detach from the gear stick end.
Anyway, thanks for your advice so far
Cheers
Josh.
Title: Re: Clutch slave cylinder swap?
Post by: Neil Choi on August 28, 2016, 05:40:57 PM
Josh,
The 36mm socket, you might have to machine down the outside a bit to fit into the hub.
Title: Re: Clutch slave cylinder swap?
Post by: colcol on August 28, 2016, 09:21:15 PM
Same size socket as a 33, you can use the standard impact socket on a 33, but for the 156, the hub is slightly smaller, and you have to give the 3/4 inch drive socket a haircut.
A standard 1/2 inch drive socket will break when trying to loosen off the drive shaft nut, as it is done up to over 200 pounds per sqaure inch, but when its been done up for 10 years, it takes a fair bit of force to loosen it off, Colin.
Title: Re: Clutch slave cylinder swap?
Post by: josh18 on September 01, 2016, 10:57:46 AM
Hey Colin I am just trying to get the damn thing loose now and am having much trouble! I don't think my rattle gun has the power! Would getting someone to hold the brakes give me enough holding force to get a breaker bar onto it and try by hand?
Cheers
Title: Re: Clutch slave cylinder swap?
Post by: josh18 on September 01, 2016, 11:05:55 AM
never mind, got the b@stard!
Title: Re: Clutch slave cylinder swap?
Post by: josh18 on September 17, 2016, 03:21:06 PM
Hi guys. Well after a trip away for work I have got the new clutch, slave and gearbox back in today. I used an engine crane to lift the box up through the bonnet. With the amount of fiddling around it took to get it in place i don't know how I could have done it by hand or with a jack.
Anyway, my first port of call before I do anything else is to bleed the clutch and make sure it works. Sounds pretty simple but I cant get the damn clutch line to slide into the plastic bleed neck on the slave! On the old one it slips in with little resistance but with the new one it feels like something is going to break if I force any harder. I have tried with and without the O-rings to no avail. It seems like the bore of the bleed neck is too small for the male part of the hose.
I did read that there is a difference between older and newer JTS clutches but couldn't find what and the clutch set I bought said it covered all models http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=122099769576.
So I'm stumped- is this common, could it be a fault of the reproduction slave?
At the moment I am thinking I might have to swap the neck off the old slave onto the new one. Not something I really want to do as it will be delicate surgery through the hole in the bell housing but I really don't want to pull the box back out agian!

Any help much appreciated.
Title: Re: Clutch slave cylinder swap?
Post by: Neil Choi on September 17, 2016, 03:39:11 PM
Presume you have pulled that retention spring out on the new slave.  As you would have to on the old one to get the line off.
Title: Re: Clutch slave cylinder swap?
Post by: bazzbazz on September 17, 2016, 04:03:52 PM
Quote from: josh18 on September 17, 2016, 03:21:06 PM
I did read that there is a difference between older and newer JTS clutches but couldn't find what and the clutch set I bought said it covered all models http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=122099769576.
So I'm stumped- is this common, could it be a fault of the reproduction slave?
At the moment I am thinking I might have to swap the neck off the old slave onto the new one. Not something I really want to do as it will be delicate surgery through the hole in the bell housing but I really don't want to pull the box back out agian!

Any help much appreciated.

The only difference in the slave cylinders was the angle of the neck where the hose plugs into, one came straight back level, the other angled downward.

As Neil said, are you removing the clip first?  ( Do we hear a big DOH! )  ;)

The neck is made from injection moulded composite plastic, it could have a defect (it's why warranties were invented).

However, I DO commend you on the idea of unscrewing the old neck and swapping them, that's what was known in the RAAF as "Lateral Thinking"! Just make sure you use a magnetic screwdriver, the LAST thing you want is a screw flying around in there!  :o

There is an idiom out there that I created myself while in the RAAF and I think it applies here:

If necessity is the mother of invention, then surely desperation is the father of it, for I have seen men with a necessity be very clever, yet wondered at how the desperate are driven to be downright bloody brilliant! - Baz
Title: Re: Clutch slave cylinder swap?
Post by: josh18 on September 17, 2016, 05:29:52 PM
Thanks guys.
I wish it were as simple as not removing the spring.
I'll have to go get some magnetic hex bits tomorrow as the missus has the running car today.

Baz its funny you say RAAF, as I am actually an ATECH in the Army! Out field we definitely have to think laterally a lot!
Cheers
Josh
Title: Re: Clutch slave cylinder swap?
Post by: Mick A on September 17, 2016, 08:43:46 PM
Hi Josh,

I've done this job many times and have come across this problem occasionally. Yes there is a difference in the clutch flexible hose, but luckily the hoses from the earlier and later cars are interchangeable, so I just swap out the hose on the car, much easier than taking the gearbox out again or fiddling with the delicate slave cylinder neck and potentially voiding your warranty on the part if you have one.

If you want the other type of hose we can probably send one up to you, shoot me a PM for info.

Mick.
Title: Re: Clutch slave cylinder swap?
Post by: josh18 on September 18, 2016, 01:30:03 PM
Hi Mick thanks for that. I thought there must be some kind of difference as it didn't look defective. I had thought about looking into swapping the hose as it looked pretty easy.
But today I managed to swap the necks through the bell housing hole with not too much trouble. The only issue was the driver socket for the magnetic torx bit I bought didn't fit down the hole! But I was buggered if I was going to take the box out again so I tack welded the bit to a long quarter inch extension and it did the job really nicely (hopefully I can cut them back apart and use both of them again). I had bought a flexible magnet to fish out any screws that dropped into the bell housing but it turned out I didn't need it.
My wife and I just bled the clutch and it went easily and i can't see any leaks anywhere. The clutch action is really positive and seems much lighter than it was before to boot.
So now the hard part is done it's just a matter of putting the lot back together again, including some new pads and slotted rotors I got for it.
Thanks for all the help you guys have given so far!
Cheers
Josh
Title: Re: Clutch slave cylinder swap?
Post by: josh18 on September 27, 2016, 11:46:53 AM
Hey guys. Thanks for all your help, Im happy to say the car is back on the road again and my Mrs is very happy with it.
Cheers