Lower Unit Rebuild - Tohatsu 70 HP TLDI

[kb7722]

I am replacing the pinion gear and the prop shaft bearings in the lower unit.

1) Is it necessary to re-shim to set gear clearance and backlash? I have heard some say that re-shimming is only required if the case is replaced.

2) Is it possible to set the clearance and backlash with out Tohatsu specific tooling?


Thanks for your help!

 

[pvanv]

Re: Lower Unit Rebuild - Tohatsu 70 HP TLDI

Verifying/Setting backlash is recommended any time any gear is changed. This is because each gear can vary dimensionally within tolerances. Once you add up all the tolerances of all 3 gears, a minor difference can add up to something significant. You need some tooling to magnify the backlash, and a dial indicator to take the readings. You can make the tools, or buy them ready-made.

Will the LU work OK without checking backlash? Yes. Will it hold up to hours of use? That depends on how lucky you get. Best to check the backlash.