bait pump problem

[Danthefishman]

thanks for all the feedback. I had an extra bait pump for a spare so I put that in and I put a ball valve at the t that feeds the wash down that way I can isolate it. theres about 10 feet of hose leading to the washdown nozzle off of the t, so its a definite possibility that there was air trapped in there and was having a hard time keeping prime. taking it out saturday to chase some tuna, I will post if the problem is solved. thanks,
Dan

[Bullshipper]

Airlock caused by airbubles getting in the intake would be my guess too, as centrifugal bait pumps will not self prime or evacuate the air from themselves under their own power.

When you run, air bubbles are created by splash at the bow and move back to the pump between the hull strakes, if you can mentally picture that. These bubbles get into the pump and can move up the hose line, accumulating in the hose line untill there is no more room for water to get in the impeller case and she loses prime, even when under the water line. Opening the sprayer from time to time might help it burp air on this trip, but like I said, fixing the intake will push it out constantly through the live well with water if there is enough force to push that water column up through the livewell sprayer that alsways stays open.

Thats why a thru hull clam pickup is used under the hull surface to constantly force air out of the impeller zone with the force of the incoming water.

If your pickup is installed right, or you just have a screened intake, it will force the water to your live well even with the motor turned off while cruising at 20 mph or faster. But screens can plug up, so its also important that the top water drains back down backflushing the screen to help clear it when turned off.

If you have a picture or can describe how it is mounted, it would help.

[CENCOASTFISH]

its an airlock, mine does that exact same thing,
if your intake has a scoop effect it shouldnt be a problem when moving above plane unless your hull has air under it at/near intake section.
At shutoff, water in system will push air out on way down, restart all fine now.
to avoid you need to make sure there is no place for air to enter the system, like from strainer gasket, clamps, washdown side etc. if it comes from under hull you may need to try different pump or hose routing or a cycling switch.

[Ghost Chaser]

Originally Posted by IN2DEEP

I think this may be the problem
Sounds like your system cannot overcome an air lock when you loose prime.
Did you say that it happens more often when it's rough?
I'm thinking that your pick-up is sucking up air during rough weather and causing the air lock (similar to backing down at the bait barge)
When you open the washdown spigot, you allow the air bubble to move in the line and the pump re-primes itself and continues to pump.
I've heard Mark Wisch recommend to make sure that the bait tank inlet hose is routed to always run down hill to the pump(non-self-priming type) to prevent airlocks.


...or you can run one of these on your transom.
Not real pretty but these will never loose prime

Have both set ups on my boat. The transom mounted pump seems to pick up water 24/7 but with slight water bubbles from traveling and picking up moving water it does not preserve bait as well as the thru hull setup. Bubbles get trapped in fin bait gills and over time suffocate the bait. Check for foamy bubbles. The thru hull set up I have also loses prime sometimes and is a rule 800gph thru hull with the "T" fitting to the washdown. I am starting to wonder if this happens when the washdown is used or airllock from the washdown pickup. Will have to observe and get back to you guys. I also have to turn off and turn on to re-prime.

FYI if this helps anyone.

[IN2DEEP]

Ghost Chaser,
I've installed the transom mount pump on two different boats and haven't had the "bubbles in the water" issue with either one.
A couple of things come to mind with yours; There's a chance that it isn't mounted low enough on the transom and the pick-up isn't in clean water or there is something ahead of the pump creating bubbles that the pump is sucking up.
These theories apply when you are under way. If you are getting bubbles while at rest, I don't know

[?? fisherman]

Airlock is your problem for sure.

They use to sell what was called a Black Box, which would automatically shut down and restart your pump when airlock occurred, but they have since done away with the Black Box and now have a pump with a so called built in Black Box.....here is your solution

ANTI-AIRLOCK 500GPH LW/BW PUMP 29-201FAA

Shurflow has these as well.


The unknown fisherman

[skipjack-20]

I've been through like five of those rule pumps, the shaft always spins in the impeller hub and stops working, crud gets accumulated, fishing line, etc. I use shureflo for my bait now, on third season, no probs. still rule bilges, 1500gph main, 3000 seccondary, they last because you can take off the strainer and access the impeller to clean it out, the smaller ones are just throw aways.