Alfa Romeo Owners Club of Australia Forum

Technical => 160 Series (90, 75, 164 Sedans) => Topic started by: supervanawesome on April 12, 2015, 09:05:22 PM

Title: 75 clutch slave cylinder mystery
Post by: supervanawesome on April 12, 2015, 09:05:22 PM
im trying to bleed the clutch slave cylinder on my twin spark 75 but when i release the nipple nothing comes out! Even when i remove the nipple and pump the clutch, no fluid comes out. The slave cylinder is still working so there is fluid in the system. Any ideas?
Title: Re: 75 clutch slave cylinder mystery
Post by: Stuart Thomson on April 12, 2015, 10:02:19 PM
Is the nipple at the top of the slave cylinder?  Usually gravity will help, just open the slave bleed nipple and fluid should flow eventually.

Why are you bleeding it, was there a problem?  If it's leaking, you'll find the fluid in the rubber boot.

HTH
Stuart
Title: Re: 75 clutch slave cylinder mystery
Post by: supervanawesome on April 12, 2015, 10:48:04 PM
Its at the side of the slave cylinder. No fluid comes out no matter how much i pump the clutch pedal, ive done this dozens of times on other cars so cant get my head around it. I really have to press the clutch hard down or else ill grind the gear. Just needs fresh fluid and a bleed. Weird issue
Title: Re: 75 clutch slave cylinder mystery
Post by: jazig.k on April 12, 2015, 11:23:03 PM
which type of slave do you have?
It does matter, even though some argue otherwise... The Twinspark slave is designed to be bolted in place while bleeding even though the nipple is to the side. The hole is drilled off centre to the bore and intersects at the 12 o-clock position inside the bore. Next time mine is out I'll take a picture to shut some of the nay sayers up...

The 3lt one needs to be rotated to the top.
Not sure what type the 2.5lt uses.

You also should bleed the master first, if you let the fluid out of the line completely.
Title: Re: 75 clutch slave cylinder mystery
Post by: supervanawesome on April 12, 2015, 11:39:09 PM
Not sure which slave cylinder my one is. I just cant fathom how the slave cylinder is working yet when i try to bleed it no fluid comes out and no fluid comes out if i remove the nipple completely and pump the pedal. Doesnt make sense. There's obviously fluid in the line but seems to bypass the nipple somehow
Title: Re: 75 clutch slave cylinder mystery
Post by: jazig.k on April 12, 2015, 11:54:35 PM
This is a Twinspark slave, as mine has fitted. Actually a good angle picture, as you can clearly, in my opinion, see that the nipple is off centre from the bore.
Title: Re: 75 clutch slave cylinder mystery
Post by: jazig.k on April 12, 2015, 11:59:27 PM
This is the 3lt one. it spins freely in its mounting bracket, only located by 2 circlips. Needs to be rotated with the nipple on top to bleed properly.


It sounds like you need to bleed the clutch master cylinder. Without that bled, you won't bleed the slave.
If you have bled it and are absolutely sure you have everything right that points the finger towards the seals in either the master or the slave. It could even be a broken return spring in the master, which is the problem mine had. No fluid pushed out regardless of the peddle movement because the master piston wouldn't return to pull more fluid into the cylinder.
Title: Re: 75 clutch slave cylinder mystery
Post by: GTVeloce on April 13, 2015, 10:32:02 AM
A quick test would be to disconnect the line just upstream of the salve cylinder (there is a union there that is easy to access) and see if pumping the pedal shifts any fluid. If nothing comes out there then forget your slave cylinder and look at the master.
Title: Re: 75 clutch slave cylinder mystery
Post by: Sailor209 on April 14, 2015, 08:49:53 AM
Remove the nipple and check that its hole is clear
Title: Re: 75 clutch slave cylinder mystery
Post by: MD on April 14, 2015, 06:17:49 PM
The Sailor gets my GONG award.
Title: Re: 75 clutch slave cylinder mystery
Post by: ALF750 on April 19, 2015, 10:27:34 AM
I always try and bleed from the bottom up,partly because I am usually working alone!   Use one of the available pump bottles, a large syringe or even a simple trigger oil pot.   This way you are pushing the air bubbles up, the way they like to go.   Drain the master with a syringe first, and pump away.  Good luck.