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Clutch Problem – No Pedal Pressure, Won’t Select Gear While Running

ardie
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ardie Experienced

ardie

Posted
Posted

Today I was driving my mates 32 and as I took off quickly from a round about and the clutch slipped slightly, then as I drove away the car wouldn’t change gear and the clutch pedal had lost all pressure. The symptoms are:

1) Clutch pedal has no pressure, goes straight to the ground and right back up again with no resistance - rules out pedal box issues

2) Car will idle in neutral but will not go into gear while running - rules out selector fork issues

3) While idling in neutral there is a faint smell of clutch

4) The car will go into gear when not running but as soon as you start it in gear, even with the clutch in, it stalls out

My friend told me that he had previously had the pedal become soft and had to top up the clutch fluid but didn’t bleed it, and then when we popped the bonnet today the reservoir was again low (we topped it up, go REPCO!). Given these things we think that it’s the master cylinder, however I just thought I would check if there were perhaps anything else which could be wrong as when I checked I couldn’t see any leaks from the master, however the car is quite low so I couldn’t get a good view, I will be putting it up on hoist tomorrow.

__PhaseShiftDown Rising Star

__PhaseShiftDown

Posted
Posted (edited)

The container on the firewall is the master, not the slave.

Slave or the clutch operating cylinder is connected to the clutch, you need to look under the car. I believe it is on the driver side, you should be able to see it just by looking under the clutch area. You'll see a rubber hose connected to the slave.

Uploaded some pics 4 ya m8, makes it easier.

ClutchLeak.jpg

Hopefully, there is a leak at either those 2 places. Once you identified the leak, fix it, then bleed the clutch as per instruction on the service manual.

Edited by __PhaseShiftDown
ardie Experienced

ardie

Posted
  • Author
Posted

Haha yeah my bad always mix the 2 names u

Thanks for those diagrams mate, really appreaciate it. Checked all those points for leaks, but didnt have a great view as the car is quite low, as mentioned before I will be throwing it on a hoist tomorrow

So everybody is of the same thought that its one of the two?

Davyboy Enthusiast

Davyboy

Posted
Posted

looks like u got it man

mine did exactly the same thing the other day (after screwing up a burnout lol) except worse

it gripped for a bit and had to change without the clutch and start it in gear. but now it will select gear but has no drive

its buggered lol

ardie Experienced

ardie

Posted
  • Author
Posted (edited)

Ok had a developement, put in a brand new master and still nothing, clutch pedal has more force, but it must have just been a coincidence that it was on its way out. Im pretty sure the system was bled properly, but I doubt that the clutch would have issues becasue there were a few minor air pockets anyway, i definetely know i got rid of most of them, i mean i probably used 1/4 of litre of brake fluid, ill go back and check it today

Im dropping the box today and going to have a look at the clutch as I can still smell it burning as it starts up but it doesnt disenguage when pumped/released. Im thinking that it may be an issue with the pressure plate or thrust bearing, however I really wont know until I get in there. If anybody has any other ideas it would be appreciated.

Edited by ardie
ardie Experienced

ardie

Posted
  • Author
Posted

Ah ok, yeah im not sure if its this, the clutch doesnt come into play at all whent he pedal is pushed and there is plenty of pressure being supplied to the lines

ardie Experienced

ardie

Posted
  • Author
Posted

Problem solved, dropped the box to be showered with a birds nest of clutch plate, basically nothing left on the clutch what so ever, and it had a few bent forks in it too.

bozodos Grand Master

bozodos

Posted
Posted

instead of making a seperate thread, does anyone have a step by step on changing the master cyl? i've got a replacement for mine, just a bit unsure on the process of bleeding and taking the seat out to disconnect the rod from the pedal etc.

ardie Experienced

ardie

Posted
  • Author
Posted (edited)

Final update, new clutch is back in, the world is once again a beautiful place with another tuff 32 back on the road.

Bleeding is very straight forward, but here you go anyway. Have a cruise through SAUs various DIY/tech articles, it’s a great resource for future ref.

In terms of taking the seat out, don’t bother, I am 6ft4 and I have never taken a seat out when doing a master (but hey I’m pretty lazy), just make sure that you adjust the push rod out so its long enough to give full travel on the clutch pedal to save you having to undo all your hard work when you bolt it all in and go to put the rod and pin back in and there isn’t enough carry. As for bleeding, its very easy, just follow the below links and you cant go wrong. Just make sure you don’t get brake fluid on your paint, it is deadly to painwork.

Replacing cylinder

http://www.skylinesaustralia.com/forums/To...amp;hl=bleeding

Bleeding

http://www.skylinesaustralia.com/forums/Bl...amp;hl=bleeding

Edited by ardie
  • 1 month later...
bozodos Grand Master

bozodos

Posted
Posted

just thought I'd update this thread - after getting another master cylinder on ebay which turned out to be stuffed too, and then buying a rebuild kit for the Aussie R31 which didnt fit, I ended up getting a brand new OEM master cylinder for a Y60 Patrol which worked perfectly.

  • 2 weeks later...
heller44 Mentor

heller44

Posted
Posted

Where did you get the new master cyl from and how much was it? After being a very rare event, ie only when other people have driven my car, my clutch pedal is doing the drop to the floor thing now and needs a new master cyl. Everything else is new last thing on the list.

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