Flapper valve on bilge pump?

[newbiedmv]

Anyone know if any place makes one. I can jerry rig a plumbing one in but it will take A LOT OF WORK. Have to remove the full back deck  and live wells to get in there. Right know I have rubber plug stuffed inside the outlet. I get about 2.5 inches of water coming in from it and the engine mount on a very very steep ramp. It's enough weight to give the 50 hp some undue effort. Also no, for some reason the manufacture mounted the pump about 3 inches high on a plate( 2005 19' Crestliner) and again full deck removal to correct. I'm too lazy for that.

[Way north bass guy]

If it’s just while launching at the ramp, could you just get the correct size rubber plug to fit in the outlet hole while you launch, as long as you remember to remove it once your tied to the dock before you head out?

[K1500]

Your bilge discharge is below the waterline?

[newbiedmv]

Dink , no it's right below the top rim, gunwale maybe, I'm not very nautical. But where I was launching is very very steep and drops off into mud fast so it's a delicate matter getting it in and the boat floating ( it floats up a foot when it releases).  It took 4L to get the trailer back up once. Also I had considerable bunk board trouble last year and I siliconed them down. It's so slick you can't get any slack on the bow line now. It's a little scary when you get the winch catch setting just right and that handle fly's around at 100 mph ??. Thank god I have a 40' safety line tied to the truck

 I have a tapered plug in it now with a line attaching it to the deck.  FYI: in case your around MD it's the Big Slackwater ramp on the upper Potomac. Oh 17' crest liner, and very heavy.

[newbiedmv]

Fixed this year. Yep 90% coming in on bilge pump exit. A rubber stopper helped a lot. But main fix is I'm ditching that ramp. Found a much better one 10 miles downstream.

Learning all the little things on this boat has been kinda of a pain but I hope I'm almost at the end. Just maybe an angle adjustment on my outboard, might be pulling to the left a little to much. Not sure yet waiting on a calm day.

Thanks for all the input, got me head working again.