Motor cranks. Won’t fire unless using starter fluid. Then motor starts/runs for a few seconds.
I bought the boat/motor thinking it was a project…not a disaster. Initially diagnosis was ignition problems (first weak spark, then (no spark). Discovered bad flywheel, stator & timing sensor. Also replaced power pack, coils, plugs/wires (correct OMC replacements) and VR/rectifier, key switch, and link/synch using OMC analyzer tool. Also checked neutral safety switch.
Got engine to fire and would run, but only while applying intermittent cold start at key switch or by manual partial enrichment of cold start switch.. If not enriched, motor would quit. Diagnosed issue as lean condition. Could be fuel restriction or air leak.
Been thru many, many subsequent procedures and replacement parts. Compression good; by-passed onboard fuel tank using new auxiliary tank with fresh gas and new primer bulb and fuel,line; new egr hoses; new intake manifold gaskets; leaf valves looked great; new throttle body seals; carbs rebuilt; rebuilt VRO/fuel enrichment switch; vacuum switch, check valves tested; link/synch again performed with OMC analyzer tool. Although fuel is in carb bowls, now the engine WON’T start except when using starter spray…then runs for a few seconds until spray is combusted.
I am now redirecting my focus to ignition testing, thinking a component may have gone bad during this 2-year process. I checked spark yesterday and thought it may be suspect. Had spark on all cylinders, but color was orange, not blue/white. Could be batteries are down a bit from testing/cranking. So, will recharge battys today AND recheck spark with correct adjustable 7/16" gap spark tester. Last time used a fixed gap tester.
So, I’m starting the diagnosis from beginning AGAIN! Given that I’m EXTREMELY frustrated, and thinking I may have overlooked something, I thought the OMC diagnostic troubleshooting tree diagram might help keep me on track.