11 replies to this topic

[min ritz ryan]

Hi all. Was driving my mini earlier, everything was fine for 10 minutes, went to drop down to 3rd and couldnt select any gears, only when the engine was off.
It won't start in a gear either without cutting out.
When it ran fine, there was knocking noise on idle until i put the clutch down.

Engine spec is 1293, standard gearbox, pre verto clutch.
Recently had a new slave cylinder installed and arm. Engine has only ran for 1000 miles after build.
Any ideas what it could be?

[cian]

Was primary gear end float done correctly? The tolerance could be on the fine side and once the Componants get warm and expand minutely it will lock up the clutch

[cal844]

Has the clutch arm been adjusted correctly?
Was the clutch retaining bolt lock tab knocked into place?

[min ritz ryan]

Yes the primary gear end float done corretly, was done by MED.
Yes clutch arm has been adjusted properly and the lock tab been knocked into place

[cian]

Go back to Med I imagine you paid i hefty sum for the engine and that should be resolved by them

[min ritz ryan]

Would i have anything to fall back on though, as it's been over a year since i've had it done ?

[pogie]

I had the same symptoms which turned out to be the primary gear locked to the crank by the flywheel on my new MED engine and box.

 

To save me stripping the clutch straight away, MED told me the check first by removing the starter motor and watching through the mounting hole for the backplate moving when the clutch pedal was pressed.  It moved ok so they then told me to try to turn the centre plate with a bar/ long screw driver with the clutch pressed.  The plate was seized which showed that the primary gear was not spinning on the crank which then meant having the flywheel machined to clear the c-washer and thrust bearing.  As your engine had been running before the problem you may have another cause but you can eliminate the primary gear without stripping the clutch by doing the above.

 

A couple of thousand miles later the straight cut primary gear inner bush span and caused the primary seal to leak, but I have heard their s/c primary gear bushes can also spin and seize onto the crank if there is insufficient clearance.

[Cooperman]

I also had a new primary gear seize onto the crankshaft tail. It was when the material of the bushes was changed to manganese bronze. It seems a bit more clearance is needed according to Mini Spares so I allowed an extra 0.001" running clearance and all was then well. That was a few years ago, but if there is insufficient running clearance the bearings could seize onto the crank. Fortunately this did not damage the crank, only the primary gear bushes which are easy to replace.

[min ritz ryan]

Okay, i shall have a look and see what hapoens.

The problem is that i've had this problem since the engine has been fitted, as i've already had to change the flywheel and starter motor because the teeth got chewed up.

[MGMiniman]

It's probaly a clutch problem. Not disengaging.

[Mini-Hazel-Nut]

I have this on my 1380 and as soon as I mentioned it to some of my older friends they suggested the the throw-out arm end is probably bent and not releasing the clutch. I have bought a billet type arm from Minisport but it`s too darn cold to fit at the moment. The annoying thing is that all gears engage lovely with a dead engine.

[tiger99]

I understand why it would be too cold to work with tools and metal parts. But maybe a quick check with a ruler of some sort might be possible? Get someone to press the pedal fully while you measure how far the end of the lever moves. Should only take a few moments.

 

That one test can determine whether the problem is definitely hydraulic, or definitely not, without dismantling anything as yet. And frankly, a hydraulic problem is the best sort because the fix is simplest, even though it may involve the dreaded clevis pin.

 

If the problem lies with the lever, plunger or thrust bearing, diagnosis gets a bit more tedious and involves dismantling.