Tsunami pump problem

[KevinWI]

Have a Tsunami 500gph thru hull pump to pump water to the livewell in the center of the boat. It is mounted on the transom next to the drain plug for the boat.
Anyway, it won't pump water into the livewell consistently. it is well below the water line, so that is not an issue.
The pump runs fine....the impeller turns fine...almost seems like it's sucking air. ....if I take out the cartridge and allow water to flow into the boat and quickly snap it back, it will start pumping water into the livewell....I can turn it off and on and it pumps water...but if I move the boat to a new location, I have to go through the same procedure again which is a PITA!

Anyone have suggestions or run into anything like this before? Have the exact same pump as the aerator and it pumps fine.

 

[PSG-1]

My Triton has the exact same pump, running to the livewell. I notice that if I go faster than an idle, it will suck air. Once I stop, it takes a few seconds to catch prime and start pumping again.

Check the strainer screen on the outside of the transom, as well as the inlet pipe to the pump, and make sure it's not obstructed by anything, such as weeds, coarse sand, etc.

Here in the salt water, the most common problem is barnacles growing inside the inlet pipe. Using a spray can of anti-fouling paint, and giving a good shot into this pipe prevents slime, barnacles, etc, from forming in there.

 

[KevinWI]

There is no screen on it, no debris...I mean I launch and sit at the launch and nothing

 

[Bob Landry]

Check your installation particularly the hoses for dips and air traps. These are nothing more than bilge pumps with different connections and normally they are strong enough to overcome air traps, but you never know. You could have a weak pump. Also take the case apart on the pump and make sure you don't have any kind of gunk wrapped around the pump impellar. It almost sounds like you have a piece of trash that's being flipped up in the water flow. Disconnect the hoses and blow air through them from both directions. Man, there's just not that much to go wrong with these pump. If all else fails, get another pump. Even if that's not the problem, you'll have a spare and sooner or later, you are going to need it.

 

[KevinWI]

yeah....none of that....everything is clean...new installation.

 

[RiverBottomOutdoors]

What if you test it while at the house?

If you cover the inlet with your hand, effectively sealing it off and causing a vacuum in the hose, does the pitch (whine...noise) of the pump change?

 

[KevinWI]

I'll let you know...it's at the marina right now...they are trying to figure out the problem...my guess is they won't be able to figure it out.

 

[KevinWI]

I've been reading some reviews...some have said they had to back up the boat to get the pump to start pumping water making them switch pumps to a Mayfair pump and it solved the problem.....sounds a lot like the issue I'm having.

 

[KevinWI]

so spoke to marina...of course it worked fine for them, so they invited me to go for a ride....I got in and indeed it worked...which of course perplexed me...and then we drove a bit, stopped and lo and behold, it didn't work....with them to witness it....we still don't know why??? They asked me what I wanted to do and I said I was just going to replace the pump. anyway, they ordered a Johnson Mayfair model to replace it to make me happy....I just want it to work without screwing around with it anymore and they just want it out of their hair as it's busy season for them working on motors, etc...not livewell winter fill in crap.

 

[novaman]

Johnson has a set of wedge washers to make a pump lay flat like they want it to be. The papers with mine said the pump should lay parallel to the water surface to avoid cavitation, caused by an air pocket. #-o If the pump is lower than the livewell, (aren't they all?)it may not be able to overcome the amount of air trapped in the line. The one I bought is a 1000 gph unit, but I switched the motor cartridges with the bilge pump, so it's now only a 500 gph rating. Apparently just having the pump intake completely submerged does'nt provide enough water pressure to overcome an airlock situation, in the pump housing , especially if the outlet points any way but straight up. Just my .02 worth.

 

[KevinWI]

Johnson has a set of wedge washers to make a pump lay flat like they want it to be. The papers with mine said the pump should lay parallel to the water surface to avoid cavitation, caused by an air pocket. #-o If the pump is lower than the livewell, (aren't they all?)it may not be able to overcome the amount of air trapped in the line. The one I bought is a 1000 gph unit, but I switched the motor cartridges with the bilge pump, so it's now only a 500 gph rating. Apparently just having the pump intake completely submerged does'nt provide enough water pressure to overcome an airlock situation, in the pump housing , especially if the outlet points any way but straight up. Just my .02 worth.

I'm afraid you lost me....are you saying you had a problem with a Johnson? or a Tsunami?.....points anyway but strait up? ... are you saying that the outlet hose needs to point strait up? Mine didn't come with instructions as the marina installed it.

 

[KevinWI]

went online and found the instructions...sure enough the outlet is supposed to be strait up.....mine lays on the side....also says it should have a strait shot up to the livewell...well it has to go down under the seats first...hmmm...this is a conundrum.....but at least I have a place to start and a probable answer to the problem. Thanks!

 

[KevinWI]

Consider this problem solved....downloaded the instrutions online and sure enough, outlet needs to be pointing up....did that, adjusted my hose and viola! I have water in my tank every time! Thanks for the suggestion. The marina had it on its side so I never questioned whether or not that was wrong. Thanks again.