ORIGINAL: Diesel Die-hard
Some of them had a manufacturing flaw which prevented the bypass from opening. These are definite non -runners! But there weren't too many of them. Chances are that yours won't be one. To check, turn it over slowly and listen for the crack as the transfer port opens when the piston descends. If it cracks open, you're fine. But even if it's no go, this is fixable if you have the equipment and skill.
Be carefully to make the transfer port higher with a dremel + small diameter grinding stone and a wood stick or aluminium rod inside the cylinder to make a right height of the transfer port. When the job is done, remove the grade away from edge of transfer port with a balsa knife and lap the edges smooth with copper lapping rod + chrome polishing paste in some few rotations, not more. Do not lap too far into the cylinder, until top of transfer port only! Wash all parts free for all dirty job and oil and assembly the engine ready to run.
The transfer height is 7.1 mm or use the 15mm aluminium rod with 6,4 mm diameter and length 12,4 mm and put into the sleeve from top of the cylinder as a stopper against the grinding stone in right height. Use smaller than 3 mm grinding stone.