Keep in mind that the OMC logo appeared on some of the first cone clutch Volvo Penta drives.
The flame arrestor cover appears to be the V/P style, yet says OMC.
Your photo does not show an OMC ESA unit, so this may mean Volvo Penta cone clutch drive.
(OMC Cobra requires the ESA [electric shift assist] Volvo Penta cone clutch does not require the ESA)
OMC engines were typically painted gray.... this one is black.
Your photo also does not show enough of the engine to see if there is an engine mounted sea water pump.
Volvo Penta has the engine mounted pump..... OMC Cobra sea water pump is in the out drive.
I'd need more photos of the engine, and in particular photos that would show if there is a sea water pump at the engine!
Back to the flywheel ring gear and starter issue:
The Ford 5.0L and 5.8L engines center the starter motor via the mounting style. So I doubt that misalignment is the issue.
If you suspect a broken ring gear tooth, turn the engine over a few degrees by hand. Now try the starter motor again. If it catches, it may indicate abroken or damage ring gear tooth.
As for the starter itself.... they may have been using the Bendix style starter motor.
No OEM is using the non-gear reduction motors these days.
The Bendix drive starter motor looks like this. These are straight through... no gear reduction and relies on the Bendix drive to engage the pinion gear.
If you end up replacing the starter motor, I'd suggest purchasing a gear reduction motor.... aka HTGR/PMGR .
The HTGR/PMGR motor looks like this. No Bendix drive, uses solenoid lever action, and has a gear reduction from the armature to final drive.
These will outperform the Bendix motor.
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