12 replies to this topic

[allpaw4]

Hey all, ran into some clutch issues yesterday. The new dump pipe has been sitting next to the unprotected clutch master for ages now, pretty much since the conversion. It only ever was an issue after the car was at temperature, and I left it idling for about 5 min. Clutch pedal would disappear due to heating of the fluid.
Now a new issue has developed. I got home from work and parked her up, no dramas with the clutch. Was left sitting for about an hour before I needed to take her out again. Usual fun of spongy clutch due to temp after sitting at running temp with no airflow. However this time I managed to put it into reverse and drive out the driveway, but the clutch went to the floor and stayed there trying for first. It was sitting on the spring if you know what I mean. Held the pedal down. But if you push down you get another few mm worth of pedal and the sound of moving fluid. Release and it comes back to the usual pedal down spot. If I curl my toes over the top of the pedal I can pull it back to normal position, but it didn't pull fluid back with it. Push down again and I have no resistance up until the point where the last few mm of travel is.

Is the master just passing fluid (or some other issue with the master) or is it the slave cylinder doing something odd?

Master cylinder is worth 110, slave worth 145. So I'm kind of keen to fix the issue rather than spend the money and replace both unnecessarily.

Any help would be appreciated.
Cheers, Ben

[migoreng]

I get this problem sometimes....usually after sitting/crawling in summer peak hour for ages...like 20mins or more.

Stepping on the clutch has no resistance til it is almost to the floor...when it's down there i can feel the friction point. I can still manage to take off...sometimes ill have to put my foot under the pedal to flick it up...

The moment you notce the clutch starting to act weird, try turning the heater to full blast and take off and change gears as much as possible. It you should gradually feel the clutch get back to normal.

[Robbks]

Question,

Why does the Secondary dump really affect the clutch,?
there's no exhaust going through it until 4000rpm..?

I realise it'll act as a heat-sink, but every single turbo with un-shielded dump would have it but worse.

[Robbks]

Convert to single,
that should fix it..

[duncanm]

I'm with Kong.

 

Its either air in the system or a leak.

 

I had a tiny pinhole in the rubber hose years ago. Clutch would work fine until driving for some time with lots of clutch action (like traffic), then it'd start getting floppy and eventually drop to the floor and stay there.

 

If your slave is old, replace both it and the hose.

 

If you want to save money - get pressure in the system (pedal depressed when working) and have a very very close look all over the hose and see if fluid is weeping out of it anywhere.

[Matt]

Try kongs clamping the pin method of bleeding and flush some fresh fluid through it

That method worked everytime ive had issues with the clutch bleed

[Matt]

Helps to unbolt the slave aswell and lift it up as high as possible above the master to let the air rise to the slave nipple

Ive even left it like this over night after bleeding...then bled it some more in the morning and got a couple more bubbles out

[allpaw4]

Sorry fellas, I'm currently running an 04 spec C engine. So really is a single. Has an unprotected 3" dump, hence the small distance to the master. Just put it into the twins forum due to being a B4 chassis, clutch system and drivetrain.
Ok, will try a decent bleed with the vice grips on the pin of the slave. Suspect the 4 years or so being next to the dump may have cooked the fluid. Time for replacement me thinks. See how it goes. Will whip the IC off on Monday and have a squiz.

[natho]

i had this problem on my b4 until i replaced the slave cylinder spring and hose with updated parts. i'd need to look at FAST again to get the part numbers. I can't remember where i found out about the spring as it's not mentioned in the TSB.

 

http://forums.nasioc...d.php?t=1065466

[natho]

OK. i think the updated spring was actually part of the updated slave cylinder - 30620aa013. I think I took it apart to compare to the original and noticed the only difference was a bigger spring.

[allpaw4]

Ok, pretty sure its just cooked fluid at this stage. Started nights tonight, too busy sorting stuff at home to get a chance to pull the IC off today - I knock off friday morning though - will have a go with it then. I'll replace the fluid and see what changes. Its started to go a dark orange rather than the standard light yellow... Failling that I'll have a good look at the flex hose and see if something bad has happened. Then its onto the master, as its the cheaper part, and again, is right next to the heat source.

 

Cheers,

Ben