Livewell loosing suction on plane

[Boosh]

Took the tinny to the bay the other day, I don’t normally use the live well but decided to get some sardines from the bait barge. I noticed there was little water in the livewell when we arrived, no water going in. Turned the pump off then back on and it started filling again. Long story short when I’m on plane I must be loosing suction. It won’t pump water again till I’m stopped, shut off the pump and turn it back on.

Threads are a little jacked where the screen goes. Couldn’t get PVC to screw on even though threads look similar. Screen screws on/off easy so didn’t want to force a PVC fitting on there to try and do a 90 elbow. Anyone else have this issue and a fix?

 

[jojo]

Took the tinny to the bay the other day, I don’t normally use the live well but decided to get some sardines from the bait barge. I noticed there was little water in the livewell when we arrived, no water going in. Turned the pump off then back on and it started filling again. Long story short when I’m on plane I must be loosing suction. It won’t pump water again till I’m stopped, shut off the pump and turn it back on.

Threads are a little jacked where the screen goes. Couldn’t get PVC to screw on even though threads look similar. Screen screws on/off easy so didn’t want to force a PVC fitting on there to try and do a 90 elbow. Anyone else have this issue and a fix?

View attachment 121422

The intake isn't meant to be used when on plane.

 

[MrGiggles]

That's normal, the pump is not going to be able to overcome the inertia of 20+ mph water going the opposite direction.

I have seen scoop deals that you can screw over the pump intake and capture water while underway.

 

[MDCrappie]

I use a piece of PVC as my intake. It goes over the transom (1/2" above transom)and down to the hull till just shy of the boat bottom. It is actually out of the water path while running. The tube will slide in the brackets and the bottom is cut at a 45 degree angle. If I want to intake water when running I push the tube down in the brackets until flush with transom. This puts the tube 1/2" into water flow and with the 45 degree cut facing forward so ti picks up water. I'll take a pic and post to show how it is as kinda hard to explain with just words.

 

[airshot]

That's normal, the pump is not going to be able to overcome the inertia of 20+ mph water.

I have seen scoop deals that you can screw over the pump intake and capture water while underway.

Some years back a friend had this issue and decided to create a scoop to pull or push water into his livewell. Started out working great until he reached 30 mph...at that speed the overflow couldn't keep up and before we knew it, the whole rear of his boat was filling with water. The lid on the live well was lifted up with water coming in everywhere !!! Glad it wasn't my idea........

 

[Still Afloat]

Well, that sucks. Were the fish happy?

 

[KMixson]

That is not a MNPT (Male National Pipe Thread) on that through hull fitting. It is not a tapered thread like a pipe thread. A PVC pipe is not going to fit right. You will damage the thread trying to fit it on there.

The intake for the livewell is on the transom of your boat. While on plane there will be no water there for it to get to the livewell.

 

[MDCrappie]

It's NPSC thread on that fitting.

Anyway here is what I use for my "on plane" water supply for my washdown pump. If I want to use while running I push the pipe down 1/2" which extends the tip of angled pipe to just below transom. As airshot mentioned, it will provide a lot of water at 30mph. That's why I designed it to only move 1/2".

 

[Zum]

I seen this on youtube....I dont own or need one but buddy seems happy....simple install.

 

[Boosh]

All super helpful info, thanks! What are NPSC threads used for? Saw one article saying air tool fittings?

 

[MrGiggles]

All super helpful info, thanks! What are NPSC threads used for? Saw one article saying air tool fittings?

Bulkhead fittings mostly. They don't seal, so they're mostly used to pass and fasten a fitting through a panel.

 

[MDCrappie]

Bulkhead fittings mostly. They don't seal, so they're mostly used to pass and fasten a fitting through a panel.

You seal the fittings just like you do other parallel thread...........................o-ring or dowdy washer

 

[MrGiggles]

You seal the fittings just like you do other parallel thread...........................o-ring or dowdy washer

I guess I should rephrase, the threads won't seal like a tapered pipe thread.

They're also used in household plumbing, showerheads, faucets, and toilets. Typically a rubber donut washer is used to seal them in that application.