Home › Forum › Ask A Member › 1957 Evinrude Big Twin 35 Skeg interferes with gears. › Reply To: 1957 Evinrude Big Twin 35 Skeg interferes with gears.
Well, your explanation makes sense. So, just reversing the positioning could affect pinion height/depth? Do the thrust washers have chamfers on them as well.
I know on newer engines, the upper washer is chamfered on its OD at the top to ensure it seats completely in the aluminum housing. The lower washer is chamfered on its ID to make sure if sits squarely/completely on the pinion gear.
I suppose it is also possible that something is causing the forward and/or reverse gear to not be positioned properly as well. This would have the effect of wanting to push the pinion upwards causing the binding. I’m concerned about the first picture here that shows the reverse gear. Something looks strange there, like it doesn’t belong/not right, perhaps it is just my eyes… In any event, if either of the gears is not properly positioned, this will try to force the pinion upwards creating a binding… But now that I think about it, inward gear positioning is limited by the clutch dog splines, so maybe it is impossible to have either gear in too far… Guess I would have to look at it.
In any event, one further test could be conducted. Reinstall the pinion, but remove the forward gear and assemble. Repeat this test but leave out just the reverse gear. If the pinion height is an issue, then the gearcase will jam with just one of the gears installed, but will jam on both tests. If the gearcase jams with one gear installed, but not the other, then gear positioning is suspect.