So, it sounds to me like it would be just as good as muffs to go ahead and install a "T" before the seawater pump. That way, when the fresh water from the hose is turned on (at first), it will run out thru the drive, thereby "flushing the drive". Then, turn on motor to have the rest flushed out. But, when you turn off the motor and the hose is still running, you'll get a quick second flush of the drive. What material would be the most effective for the T to be constructed? Anyone know what diameter hose I'll have to cut into so I know what size "T" to get?

Merc. sells a kit that works really well. I just had them put on my early model 525's when they were out for freshening last winter. I am sure they will work for your 502's. Comes with a quick connect for the garden hose and a bracket that mounts to the water separator housing. I believe they were standard on the later model 525's. Makes flushing pretty easy. I was in the same situation as you with a lift and no access to the lower unit water pick-ups.

I believe the inlet hose is 1 1/4", so you would need a 1 1/4 tee with a 5/8" or 3/4" take off. I forget what I had, been awhile. I actually made my tee's from SS. I think you can buy just the tee from CP


Added, you can use this tee and simply install a hose barb to connect your flush hose too. Ive seen some use the heavy gray PVC tees from Menards. Pump housing is plastic, so this shouldnt be any different??
http://www.cpperformance.com/p-977-1...se-12-npt.aspx

Absolutely. Thats the beauty of this setup. When I winterized, I would have a 5 gal bucket filled with AF with a hose, and one of those garden hose tee adapters that I would screw onto the hose connector mounted in my boat. The 5 gal bucket connected to 1 side of the tee, garden hose connected to the other. Id run the motor on the hose to warm it up, then after I felt the thermostat was open and oil was hot for changing, Id simply close the garden hose valve off and open the antfreeze valve at same time, and run the motor till I got a full undiluted mix of AF out teh exhaust. Then kill the motor, unhook the hose tee, change oil/filter, tuck it away for the winter

Would this work on a Volvo D6 diesel? I'm about to move my boat to a lift and need to do something like this...

If you have a 1" inch inlet hose it will.

I like this method.
I saw the T you recommended.
Where do you get a garden hose fitting with a plug and/or an inline valve to close off the garden hose leg when not in use?
Thanks,
Tom

https://www.diamondperformanceparts....roducts/295-50