Mariner 60hp big foot shaft end float

[SimonCh]

Just stripped down my mates gearbox and pressure tested (home made pressure tester worked a treat).

Found some leaking shaft seals on the main shaft from the engine and the gear selector also.

The main shaft has a fair bit of end float and when in the ‘downward’ position under its own weight it feels rough to spin as though it is fouling on the gear in the gearbox. When you lift the shaft to take the weight off it spins really smooth. Is this normal!? I wasn’t expecting much end float at all.

Cheers,

Si

[A1an]

I had exactly the same thing in my Bigfoot gearbox, I came to the conclusion that the helical cut gears would “throw” the pinion gear and driveshaft up in to a position it was happy to run in, maybe that was wishful thinking but that gearbox is still running on a fishing boat several years later. The early mariner gearboxes did like to punch extra breather holes in the side of the casing for some reason.