Originally Posted by osprey
It does need priming when in the past it probably didnt. The last but one time I had a problem though it it wouldn't fire no matter what (fortunately I was alongside on Eigg). I checked fuel was getting through, changed tanks, changed plugs (good spark) and turned it over until the battery started to discharge. I then manually gave it throttle on the linkage at the engine and it fired. I convinced myself this had been the problem and thought the linkage was sticking. I had no further issues until after diving off Skye and we were back to square one. This time it wouldn't start at all. After going through the same process I left it for another hour and it started first time. When it is running it is fine. If you have any ideas I would really appreciate them!
i had similar a similar problem with an Evinrude a few years back and after chasing loads of ghosts I eventually found it was down to the battery cables and battery not being up to the job. Make sure all your connections are clean and strong and the battery has plenty of grunt.
Modern engines have a lot of electronics that suck down the juice and without a good battery they wont work properly even though the engine is turning over..
Otherwise if you have tried different fuel tanks then perhaps its worth testing a different fuel line up to the engine and then check the filters etc (if there are any). If you elminate Fuel as a potential issue then coils, wiring faults etc would be my next port of call.