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Stag Stag clutch: broken pin-bolt or short pushrod?

Mike7777777

Freshman Member
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Hi

The clutch slave pushrod and piston disappeared from my car whilst driving. The "U" link and pin was left on the operating arm. I've fitted a new slave cylinder and slave pushrod (reputable UK supplier), I've connected the "U" link to the middle hole on the operating arm. The piston pops out of the cylinder before the clutch releases. I now realise that the original pushrod had been modified, there is evidence of poor welding on the "U" link where it attaches to the rod, in fact I can't see any clean metal at the break!

The replacement pushrod overall length is 152mm / 6".

The operating arm has 15mm / 5/8" of free play, the distance from the centre of the centre hole on the operating arm to the opening of the slave cylinder is approx 130mm / 5 1/8" minimum and approx 145mm / 5 11/16" maximum.

Receipts show that the previous owner fitted a new clutch from Rimmers approx 12 000 miles ago. The clutch was working OK before the pushrod and piston went missing, although selecting reverse was bit crunchy if rushed.

Either:

a) the modified pushrod was longer than the standard pushrod, the modified pushrod has broken and all I need do is fit another modified pushrod (hopefully!)

or

b) the operating mechanism for the clutch has broken within the bellhousing, perhaps the pin-bolt for the clutch release fork, the operating arm has then travelled beyond full extension and allowed the pushrod to fall out of the slave cylinder and hit the ground, closely followed by the piston .... which means gearbox out for repair.

I'd appreciate any comments, particularly regarding the length of the pushrod and the positioning/freeplay of the operating arm.

I think the Stag clutch is similar to the TR6, in which case the 5/8" free movement of the operating arm means it's probably the pin-bolt /ubbthreads/images/graemlins/frown.gif /ubbthreads/images/graemlins/frown.gif

Thanks

Mike.
 
Hello Mike,

a quick check to see if the clutch release mechanism is Ok within the gearbox, push the lever by hand (as you have done to get the 5\8" play) until it touches the release bearing. If all is well the bottom of the lever should be ahead of an imaginary vertical line from the cross shaft to the lever end, i.e. less than 90 degrees. If the bottom of the lever is behind the cross shaft, almost certainly the pin has sheared.
Even with a modified push rod, you will not get good release if the pin has broken (and usually jams so the clutch works after a fashion)

Alec
 
The bottom of the lever can be pushed behind the cross shaft with no resistance /ubbthreads/images/graemlins/frown.gif , still, at least I'm not missing any driving time with the salt on the road, although I'm not looking forward to laying on the cold garage floor while my Stag drips oil on me /ubbthreads/images/graemlins/frown.gif
 
Just to close this, the pin-bolt was sheared, so I replaced it. Refitted the gearbox and fitted the slave pushrod. Tested the clutch ..... and the pushrod fell out again /ubbthreads/images/graemlins/shocked.gif

I used an adjustable pushrod and attached it to the top hole on the operating arm. The clutch was heavy and the action was at the bottom of the pedal but it worked.

I drove the Stag for a couple of weeks like this and then changed the master cylinder. Success! The action is about halfway down the pedal using the middle hole on the operating arm and the clutch operation is very smooth. So hopefully that's it for a few more 000 miles /ubbthreads/images/graemlins/cool.gif
 
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