Sorry it's so long! Notes below timestamps...

7:00 Overview of what needs to come off
22:37 Press out valve stem AFTER removing bolt from tappet
26:56 Quick overview of tools I made to do this job
51:37 Timing the engine based off valve position only.

Overhaul manual: http://manuals.chudov.com/Continental...

This engine was the Y-112 run on liquid propane. Distributor needle moves counter-clockwise, firing order is cast in top of head. Front of the engine is the end with the fan-pully on it. You can get engine parts from "goodson.com", I am not affiliated with them. If you need bolts/nuts/belts hardware that isn't readily available, https://www.mcmaster.com/ (unaffiliated) has almost everything you need at a good price with fast shipping...it's where I got my grade 9 bolts. It's not too important, but the spring seats with the springs/bearings go to the exhaust valves.

Check your compression. You need compression, fuel, spark, and good timing for the engine to run. If compression is good, then spray carb cleaner in air filter to try to start. If no start, check spark. If spark is good and have fuel/carb cleaner but still no start, then check timing and/or compression. This engine had a BAD head-gasket leak between cylinders, and some worn valve guides, and a few pitted valve seats. Some of these forklifts need to be in neutral to start, and may need the lever pushed forward slightly while still in neutral to activate a finicky safety switch. If your engine uses propane, keep in mind it puts out almost no detectable (or possibly) none detectable pressure at the carb...the engine practically has to suck it out, so IMHO don't spend too much time troubleshooting the propane regulators.