The best solution is a shop manual. Although I have one, I have not timed the Iseki, but most small diesels are similar. If a manual is truly not available, the trick is to find what the injection timing is for your engine: for instance, 25 degrees BTDC (before top dead centre). If you don't know, look for timing marks on the flywheel or front pully. Disconnect your fuel pressure lines from the injection pump, move throttle to full position, pull decompressor (if it has one) and slowly turn the engine over the proper direction by hand until you see fuel moving on cyl one at the pump. Look for a timing inspection window for the flywheel or timing marks on the front pully. Timing mark should align when fuel begins moving. If it doesn't, then you need to time the pump. Either add or remove shims from the pump if it is driven by a internal injection camshaft, (add = 1.5 degrees ******, delete = 1.5 degrees advance) or rotate the pump if driven at the back of the pump. Timing is pretty critical on a small diesel. Think back when you disconnected it, did you remove any shims or how is the pump driven?