Pressure testing your drive/gearbox

[Matt]

I am currently midway through rebuilding my bravo drive, or sourcing a replacement, after having a seal fail and let some water in.

Anyway, as well as having all the tools to rebuild bravo drives on order, I thought some of the more technical/DIY members might be interested in the drive & gearcase pressure test rig I've now made.

It's a Laser Radiator Pressure Test kit (which I already had), for which I then bought a Laser 7781 adaptor and a 91-850730Q1 pump.

Unscrewed the threaded bit from the laser adaptor and joined it to the hose & thread of the gearcase oil pump with a little silicone to seal the threads.

Will fit all mercury and similar (3/8 UNC thread IIRC) gear oil fill/drain screws, which is most common for the midsize and larger motors. Portables usually use a slightly smaller thread.

[Harry]

I'm currently replacing bearings and seals on my mercury outboard gearbox too.
SEI Marine in the states are a good source for merc gearbox parts and tools.

Could I ask where you ordered the tools from? I need to get the bearing preload tool.

Thanks.

[Matt]

Any mercury dealer can get them for you - but I use https://ribsmarineparts.co.uk/