SOLID CLUTCH

Mini Magazine - - Tech -

Q I have a Mini May­fair with a re­built 1310 en­gine. Ev­ery­thing seemed well with the MoT test this week, but af­ter driv­ing the car around the drive the clutch pedal is now im­pos­si­ble to press. The clutch was work­ing 10 sec­onds be­fore, but I tried to press the clutch and the pedal had gone solid. It’s a Verto clutch we know the hy­draulic sys­tem is fine as we have tested this. It’s the arm with two nuts that won’t move - it will move out­wards and is not seized but when it gets to the 6.5mm it is rock solid. Any ideas of what it might be? Paul Dyke A The most typ­i­cal rea­son for the pedal mech­a­nism to go solid when the pedal and hy­draulics are in per­fect work­ing or­der is the fly­wheel ei­ther com­ing off be­cause the fly­wheel re­tain­ing bolt has come un­done, or the end of the crank­shaft has snapped off at the pri­mary gear re­tain­ing C-clip groove. The lat­ter is not that com­mon, but we have cer­tainly seen way more Verto-clutch equipped en­gines suf­fer this fate than any pre-Verto en­gines. The break­age tends to be caused by the for­mer – the fly­wheel bolt com­ing un­done. Maybe it is some­thing to do with folks not get­ting the lo­cat­ing key plate cor­rectly po­si­tioned, as this is much harder to do than on the pre-Verto setup be­cause of the raised wall sec­tion around the bolt head that lo­cates the thrust cup. That said, this fail­ure has been ev­i­dent on en­gines that that have not been touched since they left the fac­tory. Check­ing this prob­lem out is straight­for­ward – sim­ply re­move the starter mo­tor and ob­serve the fly­wheel as­sem­bly. It should be ob­vi­ous if there’s an is­sue.

There’s not too much else it could be by your de­scrip­tion. It may be that the re­lease bear­ing has col­lapsed, with the outer race fall­ing down and be­ing trapped be­tween the plunger/ re­mains of the race and the thrust cup. It could also be the thrust ball on the end of the clutch arm has bro­ken off. The rea­son the mech­a­nism goes solid in this case is be­cause

“The fac­tory deemed to fit the cle­vis pin re­tain­ing split pin at the back of the cas­ing, mak­ing ac­cess awk­ward”

the ta­pered sec­tion the ball is ma­chined on to sub­se­quently jams in the hole in the re­lease bear­ing. To check this, re­move the clutch arm by re­mov­ing the cle­vis pin it piv­ots on in the cas­ing, then pulling the arm free. This can be a bit of a pain to do as the fac­tory, for some rea­son, deemed to fit the cle­vis pin re­tain­ing split pin at the back of the cas­ing, mak­ing ac­cess and sight very awk­ward.

Verto clutch con­ver­sions are now wide­spread.

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