Section : Clutch

Clutch repair for utter beginners

Posted By : Ben Taylor, 20-Mar-2007, 12:13pm

I'm brand new to all of this. First time owning a classic car, and only limited mechanical experience to date. One of the most pressing issues with the new car is the clutch which seems to be rather erratic, seizing up frequently, and even when the pedal is fully depressed, the engine is sometimes engaged.

I don't know where to start with troubleshooting/ fixing it. The other postings in this section seem to address specific parts such as master cylinders etc. I don't know where to begin

Can anyone tell me where to start on diagnostics?

Cheers,
Ben

Followups :

Clutch repair for utter beginners

Posted By : Ian Mulford, 20-Mar-2007, 12:24pm

First thing to check is you actually have the clutch fluid topped up to its proper level.
Clutch repair for utter beginners

Posted By : Alan Fulbrook, 20-Mar-2007, 01:56pm

Have you tried bleeding the clutch system, you can do it with out any fancy tools if their are two of you.
I had a similar problem, bleeding it fixed it for a while but the slave cylinder turned out to have a very small leak which must have been leting air in. I bought a replacement slave cylinder.
Another thought check the pin at the top of the peddle where it pushes on the master cylinder, I also found my pin to be very worn and casing the clutch not to disengage every time.
- Clutch repair for utter beginners
  
  Posted By : Peter & Mick Lewis, 20-Mar-2007, 08:39pm
  
  as you say topic is covered in a number of threads
  is bleed screw at top of slave and feed in bottom hole
  a short rubber tube into a jar with screw open a little a good squirt of fluid should eject
  when pedal pressed. clear tube will show if bubbles are leaving. keep pipe and jar above the slave/higher up.
  to reduce volume in slave open bleed & pull slave push rod to get piston @ end of bore.
  when bled hold pedal down while nipping the bleed screw up, pump pedal to reposition the slave.
  
  pull boot from pedal box renew worn clevis pin and weld washer on pedal if hole is worn,
  you could go up a size on pin to the reclaim worn holes if possible
  the free play between pedal /push rod and master cyl is not adjustable, this must be a small amount, no play and cylinder will not recuperate(refill) when pressing pedal.
  to get get ours right we modified the m/cly support bracket and slotted the holes to the baulhead which allows some movement to minimise free play ... some thoughts peter
  - Bollocks!!!!
    
    Posted By : Ben Taylor, 21-Mar-2007, 07:03pm
    
    Clutch has got dramatically worse suddenly and car is now pretty much undrivable (clutch won't disengage at all, and the tachometer's broken). I tried bleeding it (which proved to be a right ballache- taking the seats out and all!) which did nowt. There were only a tiny amount of bubbles in the line. I did it pretty much as directed in the Haynes manual with no obvious problems at the time- however it still doesn't bloody work!
    
    The Haynes manual suggests another cause of this is "Rusted Splines on driven wheel". What does this mean, and is it likely? Is there anything else I should be thinking of doing? In addition the gearbox tunnel cover in my car seems to be made entirely of cheap cardboard held together with silver masking tape!
    - Bother!!!!
      
      Posted By : Mark Astley, 21-Mar-2007, 08:26pm
      
      Hope that the crank thrust washers haven't fallen out.
      Without the engine running, get someone to depress the clutch pedal. If you can see the front pulley moving out from the engine front then it's likely they have. Doesn't take much engine running with them out to destroy the block face either. I'm sure there's been other threads on this before.
      
      Other things,
      The clutch arm pivot pin might have dropped out or worn the hole oval, you can see it from above at the drivers side of the bellhousing.
      The clutch operating arm might have cracked or broken inside the bellhousing.
      The slave cylinder might have slipped backwards in its pinch mounting.
      The clutch bearing might be completely worn out.
      
      The "rusted splines on driven plate" suggests that the clutch plate isn't sliding along the gearbox input shaft splines and stays in contact with either the flywheel or the clutch cover. Probably unlikey as the clutch would probably become stiff rather than failing suddenly.
      
      The tunnel cover is probably the original factory one. They were a pressed fibre thing. Not the most robust .
      
      Yours
      mark
      - Bother!!!!
        
        Posted By : Ben Taylor, 22-Mar-2007, 11:26am
        
        Thanks for the helpful advice. I've had to step away from the car for now as it was getting dark, and I probably won't get another chance to seriously play with it until the weekend due to work.
        
        I'll check the crank thrust washers at the first available opporunity. Where do I look for the clutch arm pivot pin? (haven't fully got my head around the anatomy of my spit yet!)
        
        Assuming that's ok, I might quickly try peters suggestion of reducing the volume of the slave cylinder to see if that improves things.
        
        I've ordered a shiny new moulded plastic gearbox tunnel and given the (filthy) underseat floor a good clean out. It looks like things under there have never been looked at since the car was new! No rust thankfully and the slave cylinder and hydraulics seem in good nick- no signs of corroded paintwork or leakage.
        
        Of course the undriveability thing is annoying (it's my only car- but that's no disaster as I don't really NEED one), but I'm actually quite enjoying the guddling under the bonnet.
        
        Unfortunately the list of projects is growing every time I get in the car!
        
        Bother!!!!
        
        Posted By : Calvin Andrew, 22-Mar-2007, 11:55am
        
        "Unfortunately the list of projects is growing every time I get in the car!"
        
        Ben, welcome to the wonderful world of classic motoring.
        cheers Calvin
        
        Bother!!!!
        
        Posted By : Peter & Mick Lewis, 22-Mar-2007, 08:33pm
        
        think of the time it takes and double it then look at the cost and treble it then when youve done it twice instead of once ,,, spent the pension fund and the crown jewels you start to correct 40 odd years of cock ups and mis appropriated repairs that you unravel whilst convincing the brain this is a realy good hobby ....Love it....
        
        Ben....On the clutch front does the pedal have any resistance or load for all its travel ... how does it feel ? ???...
        
        another thread not mentioned (but ulikely )is diaphragm finger fracture gives serious drag followed by being unable to disengage but but if ones broken off you get some serious expensive clattering as all the bits thrash round in the bell housing
        .....happy motoring peter
        
        Bother!!!!
        
        Posted By : Ben Taylor, 22-Mar-2007, 10:43pm
        
        Hi Peter,
        Clutch feels marginally heavier than my old Ford Focus- there was a wee bit of travel on it, and before the problem got acute I felt the clutch disengaging slightly.
        
        I've decided to do something rather drastic... I'm going to replace the hydralics and the clutch assembly completely. For four reasons:
        1) it looks like it (at least the gearbox/ slave cylinder) haven't been touched since 1978, so it's likely to be worn and buggered
        2) I'll be able to have a good poke around the old cylinders/ clutch to see what actually caused it (a bit like a post-mortem)
        3) I'll be able to have a wee play with them all, take the old ones to bits, repair them and play around with them to fully understand how a clutch works (a bit like dissection/ prosection back at medical school)- for future reference
        4) they'll be shiny new bits in without any gunge in the hydraulics, and with new flywheels, driven plates etc.
        
        The whole lot is costing me Â£160 new from various shops. One of the partners I work with has had his modern eurobox Merc in for repairs recently - some steering wheel sensor has failed which is costing him Â£400.
        
        All hail king Ludd!!!!
Good Stuff!

Posted By : Ben Taylor, 22-Mar-2007, 11:04pm

I must say though, in the last few days, with a bit of getting stuck into things I'm beginning to get my head around it all! On Wednesday if you'd said "look at the pin which connects the pin and the master cylinder..." (as somebody did) I would have looked at you as if you were from mars (and did, in fact. No offence intended!). Now I know exactly where to look, and what to do (unfortuneately it's not as simple as that, that pin's fine- bugger!)

Thanks a lot for your help everybody!!! Although my car's not as reliable as the old focus, and not under warranty either (!), this is exactly why I got it. When I press the (soon to be rebuilt) clutch, I won't think "ho, hum- changing gear again", I will think "yay! I rebuilt this bit, I know how it works and it's my own handicraft I'm pressing on!")

Sad I know, but hey, ho!
- Good Stuff!
  
  Posted By : Ben Taylor, 23-Mar-2007, 00:39am
  
  Really enjoying owning a classic car!
  - Good Stuff!
    
    Posted By : Peter & Mick Lewis, 23-Mar-2007, 08:30am
    
    hope you looked at the NEW clutches canley list at Â£47... recons are a whole new ball game of poor compromise and specifications often by nature of how you recon a pressure plate are lost in the mortuary ...peter vit6
    - Good Stuff!
      
      Posted By : Ben Taylor, 29-Mar-2007, 07:30pm
      
      Chickened out in the end. Didn't have the courage to remove the gearbox by myself (and cruicially, to put it back together again afterwards!). Therefore I took it into a local garage. Clutch itself is fine, but the bores of the master/ slave cylinder are knackered, so they've replaced the hydraulics, and now the thing's going like a dream.
      
      Next project: replace the tatty hood