I knew there were good people on this list, any Land Rover Series truck owner has to be.
Starting a diesel does not have the kick back problems of a gasoline engine. A handcrankable diesel will have a big flywheel and compression releases. You engage the compression releases on a diesel and then get the engine spinning as fast as you can with the crank. When the engine is up to speed, you quit cranking and simultaneously drop the compression release on one cylinder at a time. A good engine will start on one cylinder on the first try and give you time to drop the other cylinder compression releases at your leasure. Hand cranked my Volvo MD2b for nearly 10 years without a problem though it was always in warm weather. The 3 cylinder MD3b Volvo could be hand cranked but it took a lot more effort and was just about as large a diesel as I'd attempt. The single cylinder MD1 was a piece of cake. FYI, without compression releases, you are not going to be even able to turn over a Diesel, let alone start it. So if you don't have one of the Volvo's, Yanmar's, SABB or other engines with compression releases, forget it. I don't know it if was this list but someone had furniture in the way of the crank on their boat. My W32 had to have the crank handle extended by about a foot to clear the furniture and steadying block added to the cabinet. In our case, the steadying block was just a 1 1/2 thick piece of teak with a slot for the crank to slip into.
A gas engine is fired by an electronic spark that fires before TDC so you have to be very careful that the engine doesn't kick back. The crank has a one way design so the crank disengages when the engine fires. Unfortunately, if the engine spins back, the crank will spin back and can do serious damage like a broken thumb. On my Series truck, I roll the engine over till it's just coming up on the compression stroke with the ignition off. Turn on the ignition and then put everything into a 1/2 rotation of the crank. My Series would normally fire on the first try. Never had the strength to actually get the engine spinning, without firing. My MGA had a higher comlpression engine but 600cc less displacement. I could get that engine spinning with the crank. Used to have to hand crank it in the winter till there was thaw as the starter Bendix would ice up. It didn't like to start on the first revolution when it was 20 degrees so the ability to get it spinning was critical.