Slave cylinder replacement/ bleeding

[Jeff E]

If you are reading this before you start, that's good because you can research this forum, the MY350Z.com forum and You Tube and learn it may not be straight forward. If like me you screw up and end up with more air in your system than a Lilo, the following may help.

What did I do wrong. Sucked out the old fluid from the reservoir, took off the old slave cylinder (SC) and let the down pipe drain. Fitted new SC,filled up reservoir, pumped (many times) clutch pedal and no pressure.

From reading I learnt that you cannot back bleed the 350Z system as the master cylinder (MC) won't let you. Some say it is because the clutch adjustment has been changed but sure my car has not been altered and still could not back bleed.

So here is what I did. First push the piston on the SC fully back and hold with a G clamp. ( see You Tube "bleeding a clutch by blocking the slave cylinder") . Connect to the banjo on the down line. Now you need a new oil squirt gun and 2m of clear vinyl pipe (necessary as I was singe handed). Fill oil gun with brake fluid (BF) , connect pipe and pump BF through so no bubbles in pipe. Connect pipe to SC bleed nipple . Now go up top and locate MC which is behind and below clutch reservoir. You will see the pipe coming out of the MC which feeds the SC. The plastic surround above the MC is held in place by 5 plastic buttons. Pull these out and remove plastic cover to give better access to top of MC. Disconnect the SC feed pipe from the MC. Put small container under MC, eg paint spray cap. Go below and undo SC bleed nipple. Back up top and as you have 2m of pipe you can pump the oil gun and watch until you see BF coming out of the SC feed pipe. Go below and tighten SC nipple.

Now bleed MC . Fill reservoir with BF and pump clutch pedal until BF coming out of MC. Then if you leave clutch pedal in up position you will find BF gravity flows out of MC. With clutch on floor nothing flows.

Put it all together. Put SC feed pipe into the top of the MC so it is in the BF ,but do not screw it in. Leave clutch pedal up so there is a slow flow of BF out of the top of the MC (keep close eye on reservoir level) .Go below and undo SC bleed nipple. Back up top and with one hand, pump the oil gun until BF is coming out of SC feed pipe and no more bubbles are appearing in the top of he MC outlet. You will now have two flows coming together. Keep pumping and with the other hand push the feed pipe fully into the top of the MC and screw the SC feed pipe connector back into the MC. Go below and tighten SC bleed nipple. Finish screwing SC pipe feed into MC. Top up reservoir and go below. Take off G clamp. Spring in SC will push cylinder out drawing BF from reservoir. Fit SC. get in car and push clutch , pressure, start engine and put into reverse. Can't believe it !

What would I do if starting afresh. The main objective is to minimise air ingress. Don't suck out the dirty fluid from the reservoir. It's the good guy. You can flush it out later. I believe the down pipe to the SC is a flexible. If so I would clamp it as close to SC as possible and would not take off the reservoir cap. Remove the old SC. G clamp the new SC as described above and fit to the down pipe banjo. Pump clutch pedal 4-5 times and keep it in the on the floor position. Now release the pipe clamp. Repeat clutch pedal pump 4-5 times, keep in on floor position and undo the SC bleed and let out air /BF. Then bleed as per the workshop manual. This way you only have the air between your pipe clamp and the SC bleed nipple to get rid of. When no more bubbles release G clamp and spring will push cylinder out and draw BF from reservoir. Fit SC.

 

The last paragraph is my opinion. What I have written above that is what I did and can vouch for.

 

ps to see the back bleed procedure go to You Tube and search " BMW,VW,Porsche Clutch Bleeding" or MY350Z.com and search " whats the easiest way to bleed the clutch"

Edited April 19, 2016 by Jeff E