Spinning the oil pump drive with a drill would be of major importance...
Over-rated, in my opinion!
Your engine will have lost no more oil at the crank/cam bearings, cam followers, etc........, than if it had been sitting for only a year. (nothing new here..... engines undergo this often!)
During your initial cranking, oil pressure will build enough to replace this thin film, IMO.
Cam followers may require more. Not a deal breaker!
If up for the task of R & R'ing the ignition distributor, and re-indexing it correctly, it certainly would not hurt to prime the oil system.
Necessary? NOT in my Opinion!
I'd not do not do this if unfamiliar with the procedure!
Quite frankly, I'd be more concerned about the cylinder walls after three years of sitting!
Note: oiling cylinders on V engines may not be effective. Gravity!
Oil followed by a blast of compressed air may be more effective!
I would not worry about spinning the oil pump.
+ 1.
Is this your first boat? If so, I would look into converting the OMC drive to a Mercruiser Drive. There are not too many mechanics , at least here in Jersey, that will work on OMC. You can find someone who will work on it I'm sure, but do they actually understand they procedures involved in setting up the shift adjustments.
Converting to a Mercruiser will make the boat reliable. You will spend more time using it and less time trying to find used parts to fix the drive.
Agree with the limited availability of good OMC mechanics. They do have their issues.
(See Stuart Hasting's web site for many details)
Again, my opinion only....... any of the Volvo Penta SX or DP-S drives (of the correct ratio) will also retrofit the Cobra.
A kit is needed!
With the V/P SX/DP-S, you get completely away from "Dog Clutch" gear engagement, and the ESA can be completely eliminated.
The OMC ESA (interrupt and over-stroke switch) and related shift cable arrangement is one of the OMC Cobra issues in the first place.
Personally, I'd first opt for the V/P conversion............ the Merc or SEI secondly!
However, we're getting off track here with any suggestion like this......, at least until you confirm if the drive is either OK, or not OK!
BTW, much of what may help you with the remaining fuel related question, will depend on the climate where this boat had been stored.
If warm climate, the fuel will have had a lessor chance of surviving.
If cold/cool climate, fuel can occasionally survive.
Best bet..... do as others have suggested, and remove it completely!
Begin fresh! New fuel, new filter, new fuel pump (if you suspect the diaphragm is bad).
Good luck with it!
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