On my own boat I have a drain hose attached to the drain plug....

On customers boats, I used to just put a pump in the dipstick or, in most cases with a Chevy, put my oil pump primer in the distributor hole and put a 1/8" MPT by 1/4" hose barb in the sender hole with a piece of hose to a bucket and let her rip.

This worked great on boats in the water, but you did have to reset the timing when you were done...

GT

i have a ford and theres no other way to get the oil out other then goin through the dipstick hole.. it takes a little bit of time but it works beautifully

I got it at the local speed shop here in Hesperia CA the shop is called Dales speed and marine, their website is www.dalesspeed.com. The pump is called Panther by marine tech. Hopefully this helps you out.

I never had any luck going through the dip stick so this time I bought the drain kit from CP. It cost $30 delivered and it has a hose that extends out through the hull drain plug. It may be slow but it looks to be very easy.

I've had pretty good luck with needing to pull the engine around when the oil is due to be changed 

I've had one of the drain hoses hooked up but couldn't use it before because the hose would not fit through the bilge drain hole because the transom wood covered half of the hole.  I corrected that problem while the jet was out this time.    Now lets see if I can get to the next oil change without having to remove the engine   

I went to NAPA and asked them for a manual pump to suck fluids.  They pointed me to the manual pump and a adapter for the hose and $30.  the job was 5 minutes to suck out the oil.. 

Much better than waiting for hours to have the oil drain out the hose.  Suck away......