Hey guys, sorry for the stupid question but when changing oil in your boat does the filler cap need to be on or off? We are using an electric drill powered pump and cant seem to get much of the oil pumped out.

I'm not sure I understood this but unless it's a trick question, it needs to be off...

I never really got much oil out buy using a pump through the dip stick hole. It's better to drain it out. But if you can't then be sure to run the boat first, so the oil will warm up and you can suck it up easier!!

Good Luck!

Thanks, its not a trick question. We have been trying it with the cap on and off and cant seem to grt much out. We ran the motor for 15 mins to get it warm.

Basically the drill pumps suck, oops-I mean they don't suck to well. You need to get one of the pro type pumps or a vacuum canister type if you are gonna do it through the dipstick hole. Or install drain hoses in the oil pan and drain them from the bottom.

That's what I tought: best drain it from the bottom, I never attempted to do it through the dipstick hole...

I have one of those quick drain hoses out the bottom of the oil pan, i stick the oil sucker down the hose, gets to the oil in the bottom of the pan. We use the big blue vacuum pump like bought a west marine.

I also have a hose running from my drain plug hole. I have the blue canister vacuum pump... works great as long as the oil is warm. Though lately, I seem to yank the motor out every time it's due for an oil change.

I've had really good luck with the electric pump
that clips to your battery. I goes thru the dipstick
tube. Just get your engine good & warm first.

Those take forever. Lot better off to get a turkey pan and drain from the bottom.