1995 Johnson 40 hp

[Rick.]

Hello all. I want to pressure test the above motor gear case. I noticed a tiny bit of milky oil when l resently was getting it ready for winter storage. I drained it completely and found the initial drainage was contaminated but only a very little. The rest of the oil (probably 95%) looked normal. I want to do a pressure/vacuum test but my manual doesn't say anything about it. Would anyone know the correct numbers I should pump it up/down to? Also I'd like to hear comments as to why such a small amount of the oil was contaminated. The motor had not been used in the previous two weeks but I thought once it was contaminated it would make all the oil milky.
Thanks, Rick.

 

[racerone]

I consider those gearcases to be less than robust.-----Tear it apart.----Inspect gears.---Replace pinion bearing.------Install a seal kit.-------Pressure test at 5 to 10 PSI.

 

[Rick.]

Thanks. Is a vacuum test also recommended?

 

[Crosbyman]

10-15 lbs either way (pressure and vacum will show up leaks )

it coud have been just bad / reused nylon washers on the oil plugs

give it a try with new washers and proper torque and if the water does get in well you know you ahave a reseal job to do. look for mono filament pieces on the prop shaft...:-(

I purchased the red pump shown ... works ok
Got the screw adapter for the gearcase from those oiler pump kits used to refill the gearcase.

 

[racerone]

If seals have 25 seasons on them, then put a seal kit in.