Hi Nightback,

Sorry, I don't know anyone (or anything!) in North Carolina... I'm in Ottawa, Ontario Canada. You might check this website to see if any garages are listed - the website was just upgraded, so I don't know where to look for garages, clubs etc.

Re your idling problem - you should start a new thread with idling problem in the subject line - this thread is an old one about transmissions. You would get much better responses than I could give on this problem. That being said, my Mini's idle speed tends to vary with engine temperature too. It is just the way it is - different engine and configuration than yours, so not directly comparable.

I would check that your carb oil is filled (probably not directly affecting, but you never know), that the throttle shaft moves freely when cold and hot, that your throttle cable moves freely and has a tiny bit of slack in the idle position, both cold and hot, that the choke mechanism also operates freely cold and hot. In other words, check anything that might "adjust" idle speed as it heats up.

I'm guessing you have a SU HS type carb (since you said you inspected the fuel bowl). Check that the main jet is properly centred. It may be sticking a little and frees up as the engine and carb warm up.

Dan my 69 MKII idles ok until i take it out for a 4 mile fast drive then when it sits at idle after about 3 minutes starts to do 1 or 2 short sputters bringing down idle like a semi stalling then back to normal idle, it does this about every 4-5 seconds, if I pull choke a little and raise the ide to 12K it fixes but if i try bring idl to 800 it goes back to symptoms as explained, i have new fuel pump, new distributor/wires/coil/sparkplugs/airfilter,tried spraying wd40 around carb still same, i tried running without vauum adv. still same, i tried lifting off the float chamber and cleaning, still same, tried slight timing adjustments, still same, cleaned inline fuel filter, checked for cracked fuel line, still same, tried adjusting air/fuel mix , still same, i use 93 octane fuel...any ideas? 

Dan do you know of anyone who works on classic minis in and around Raleigh North Carolina?

Coopertune (Steve Gibbs) has not posted her in about 2 years. Click on his profile and try the email address listed.

Steve where are you located? i may need to have mine rebuilt

And you can eliminate the throw out bearing. It works the other way. No noise when the clutch pedal is up. Noise when the pedal is pressed down.

Yes, when you press the clutch, EVERYTHING "downstream" of the crankshaft stops turning, so going quiet is a good indication of a bearing or gear failure. When the engine is running in neutral, the drop gears are spinning, as are all the gears on the trans main shaft.  It's not too intuitive for people, but no matter what gear you are in, ALL the gears are still turning in constant mesh...

If you have a loud whine while driving or in neutral,  I would suspect the idler gear bearings. If a rattle or grinding noise, that seems worse under load in a particular gear, it's likely inside the box. if an irregular "crunching" your 3 synchro box may have chunked up 1st gear. I'd only keep driving it if you are willing to sacrifice the gearbox case, the flywheel housing, and the drop gears! If it is just a 3-synchro, keep driving and let us know what ultimately happens!

It's probably the idler gear bearing if the noise is really obvious and the gearbox is operating normally otherwise. Any metal or other odds and ends in the oil? If not then bearing failure in the gearbox is very unlikely, but not impossible. Often the advice for minor idler gear bearing noise is keep driving it until it gets really bad.

Kelley

Throwout bearing perhaps.

Watch the crank pulley when you push in the clutch. If it moves out the thrust washers are toast. Unlikely to be the source of the noise either way. The transmission does whir some which does go away when you push in the clutch.

You must think there is some kin of magic here. She's not new for sure and when you push the clutch you stop the gears and tranny bearing. I have seen plenty idler bearings fail, first motion ball and inner and outer support bearings go. Third motion spigot worn and double ball bearing spacers fail. I'll be glad to rebuild yours or replace with 4 synchro AA remote and rebuild that if you like. If the idler bearings are gone the tranny case and clutch housing will be in question. Steve (CTR)

I've got a '64 MG 1100 in the shop for a gearbox noise. It has the sound of  a bad bearing, and only goes away when the clutch is depressed.

Is the 1st motion shaft bearing the likely culprit?

How about crankshaft thrust washers?

Any thoughts?

Thanks