What is needed to pressure test Cobra drive?

[Gary H NC]

I have my outdrive off the boat and in the garage for the winter. I drained the gearcase lastnight and noticed just a little milky color in the oil.
I have already purchased an upper gearcase seal kit because i need to replace the water pump adapter plate,new impeller ect.
After i do all the upper seals i would like to pressure test it just to be sure.
What parts do i need and what is the procedure?
Thanks for any input.

 

[WillyBWright]

Re: What is needed to pressure test Cobra drive?

Stevens Instruments makes the tester that most shops use. It's a hand pump with a gauge and a hose with a connector on the end that you screw into a vent or drain screw. They have pressure and vacuum testers. Both should be used. You probably don't want to buy one just for one project. Perhaps you could have a shop do it for you for a small charge. If you buy the parts there, you can probably talk them into doing it for free.

You pressurize or evacuate the drive to a given spec, twist the shafts, and watch the needle. I watch it for a minute or two, then let it sit for an hour or so and look at the gauge again. It might fluctuate a tad over that much time due to temperature changes, so a small change is probably not a big deal. If it zero's out or drops to less than 3/4 of what you put in, there's probably a leak.

Google Stevens Instruments and you can have a look at one.

 

[Gary H NC]

Re: What is needed to pressure test Cobra drive?

Thanks Willy, The only shop near me is not very well thought of..but they may not stick it to me too bad to do a pressure test.
I'm tempted just to re-seal the upper and make my own guage and line to put a few psi in it.
I'm suspect of the water pump shaft being the leak.The pump adapter plate was shot with corrosion so i bet the oring and seal could be gone.
I got the bolts soaking with PB Blaster untill i get time this week to tear it apart..
What started out as a bellows change and ujoint service is getting expensive!
I got seal kits,bellows,impeller,anodes on the way....