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I'm having a heck of a time trying to separate the crankcases on my '76 3 /12 Sport. The front & rear dowels have been removed, and "yes", so have the two "hidden" cap head screws. I have a few mm gap all around, but the blessed thing seems to be sticking at the crank. Any suggestions?

Heat carefully applied?

Yes, around the casing for the crank.

After searching YouTube I decided to buy a crank case splitter/separator tool. Yet another tool required for this bloody bike!

Is yours like mine with the ball/roller bearing main on the flywheel side? If so it sounds like that inner race may be tight on the crank axle. Heating the case won't help as the bearing is retained by a plate inside. Your new puller may do the trick but it's a bit unlucky for you-I've never needed one for of those for a Morini.
Still, the new tool will come in handy for other projects eh?

I'm not sure what sort of bearing is on the flywheel side, but the crank aint moving! Spins nicely though. After I split the cases, the tool will actually come in very handy for pushing the crank through the (disintegrating) bearing on the oil pump side. I don't think it will push out that side very easily either!

The early engines have a ball race on the timing side. When this was replaced by the plain bearing, Morini added three small cap head screws to the crankcase to pull in and retain the plain bearing housing.

If you don't have these screws, then you have a plain bearing engine. The crank should be a sliding fit in the bearing and simply pull out, but this is not always the case. If you heat the case around the bearing to around 100-120C, then the bearing should slide out of the case and can be removed from the crankshaft afterwards.

EVguru wrote: ↑16 Sep 2021 19:11 If you don't have these screws, then you have a plain bearing engine.

Of course, Paul means if you don’t have the screws it’s a ball bearing engine. But he knows that. Just thought I’d correct the typo to avoid confusion

1976 model.

You have the bosses for the bearing housing screws, but they've haven't been drilled and no screws are fitted. I've only ever seen that on 250 2C cases, which retained the ball race on the timing side. I would have to guess that they were made during the changeover to the plain bearing crankshaft.

Thanks! I wonder if my bike is a bit of a factory "bitza", because the timing marks on the flywheel are not where they should be!

Or replacement engine cases/engine , is it stamped A, K or J (250-2C) lower left side, or nothing at all.
The boss for where a never fitted nuetral light switch would go on later machines is different too.

That’s an impressively clean tool board by the way. My crank had a roller bearing conversion so the three screw points have some sort of weld blobbed on them. Insufficient data to determine if this was a good idea - after 9 years.
John

That’s an impressively clean tool board by the way.

Thanks! I retired almost 2 years ago and we finally moved into our very own home in the countryside. After years of renting, it's nice to set up a permanent garage! I decided I wanted a really big peg board. I joined two small benches together, built a wooden frame behind, and attached a full sized peg board. This has been placed in front of a useless glass sliding door. This photo was taken a while ago - there are a few more Morini specific tools on the board now!

is it stamped A, K or J (250-2C) lower left side, or nothing at all.

This is the only thing stamped on the cases (other than the "S" under the front cylinder).

I also solved the mystery of the flywheel markings not aligning. I was reading through "The Blue Book", and discovered the marks align with the mark at the 9 o'clock position on the case. D'oh!