61 Engine Update

[Mr Rusty850]

The restoration of my 1961 mini is progressing slowly but surely. As I bought the car in almost completely original condition my aim has always been to restore it, whilst maintaining as much originality as I can. However when it came to the engine and gearbox I wanted to engineer out the cone synchromesh and the oil fed primary gear. I looked at the factory-supplied ways of doing that but parts were either rare as hens teeth or ridiculously expensive, so I’ve pursued a different solution. I bought a cheap engine and gearbox from a 65 model. The gearbox and diff with the help of forum members has now been rebuilt and I’ll be moving onto the engine soon.
It is my plans for the engine that I need thoughts from you guys on whether it will work. To get rid of the wet primary gear I plan to use the crank, flywheel and diaphragm clutch from the 65 engine and use them with the block, rods etc from the original engine to retain the original engine number. It all looks as though it will fit together but before I send everything off to the machine shop is there a glaring problem with this plan that I’ve overlooked?

Thanks,
Barry

[mk1]

As far as I can think this is a perfectly sensible solution to your problem & it should work A OK.

[woodypup59]

Check the main bearing diameters.

IIRC, the oil fed primary gear crank has smaller main journals (1 3/4" dia) than later, dry PG types - hence being called "small tail".

The conversion kit to dry PG involved plugging the oil hole and a modified PG.

Not sure when they went to 2" journals.

[mk1]

The "Small Tail" refers to the taper & diameter if the crank tail where it taper fits to the flywheel. As long as you don't try & mix crank, flywheel & primary gear, you should be OK.

I have just had a good hunt through the parts lists & manuals & can confirm that bearing size in unaltered throughout 850 production.

[CooperTune]

I have stumbled on a mini Super project which has a MG1100 with remote in position. I also want to restore as correct as possible. I try to back track though owners as far as I can get information. It seems the camshaft broke and was discarded. I have picked up a 850 from a 72 Pup. Yes, it has rod with pot joints. If I planned to work an 850 hard I'd line bore and add additional cam bearings. I have not yet stripped the replacement unit. Any chance anyone here know if 850s received all cam bearings later in production? Steve (CTR)

[mk1]

As far as I know the 850 cam ran in the block throughout production.