How do you get your non self priming pumps going

[jeff356]

Every spring there is a battle that I wage with 2 non self priming pumps to get them up and running. On the air conditioning and generator AC pumps they do not self prime and although I try squeezing the hoses to induce suction to get the water flowing I end up taking off the hoses at the sea cock and pouring water in to get them primed.

Just wondering if there is a safe and reliable way to install a T connector in the supply hose from the sea cock to the pumps to fit on a hose making quick work of getting water to the pumps. Also could use for winterization I would think making it a win/win.

Any ideas that might work better, always looking for a better mouse trap.

Jeff

 

[justsomeguy]

Any ideas that might work better

Re-locate these non-self-priming pumps to a spot that's below the waterline? And try to route the inlet hoses so there is no fall, all rise to the pumps, to eliminate possible air-gapping.

I know, what a friggin' hassle.

 

[Don S/V ILLusion]

It's usually pretty simple to just unscrew the filter allowing air to escape and water to enter.

 

[All U Get]

Garden hose and back feed it through overboard through hull.

All UGet

 

[Jackdaw]

Install an inline T with a small flexible line running off it, with a valve on it. Open the value to 'burp' the line.

 

[jeff356]

Install an inline T with a small flexible line running off it, with a valve on it. Open the value to 'burp' the line.

Is the T made out of plastic or rubber? As a side note I ALWAYS close my sea cocks on leaving the boat.
This is actually what I was looking for.

Thanks

 

[Jackdaw]

Is the T made out of plastic or rubber? As a side note I ALWAYS close my sea cocks on leaving the boat.
This is actually what I was looking for.
Thanks

I've seen this on dozens of boats. Typically the fitting is hard, and made of the same material the rest of the fittings are. In general you want to make the burp line as small as possible. That way even if it broke or the valve was left open, the amount of water coming in would be very small. Some people (JIC) will run the burping line up the side of the hull and above the waterline.

 

[Gunni]

The air purge is the small valve just after the March A/C pump, it purges air above the pump convulute. The two white lines run to my two A/C units and the blue intake line connects to the seawater strainer. Per ABYC there should be a drop from your A/C units back to the pump, down to the strainer and finally the thru-hull. Everything shown here is below the waterline so I rarely need to prime the pump, but if I do it is a 10 second job.

 

[Marc14857]

I have a plastic tee fitting on the discharge side of my AC pump with a small 1/2 turn valve off of the tee. When I line up the system i.e. open the seacock I can open the bleed valve and most of the air bleeds off. I start the system up and get a steady stream of water from the bleed valve and then close it. After that I rarely lose the prime. I always close the seacock when we leave the boat unless we are in dehumidify mode.

 

[jeff356]

View attachment 136246
The air purge is the small valve just after the March A/C pump, it purges air above the pump convulute. The two white lines run to my two A/C units and the blue intake line connects to the seawater strainer. Per ABYC there should be a drop from your A/C units back to the pump, down to the strainer and finally the thru-hull. Everything shown here is below the waterline so I rarely need to prime the pump, but if I do it is a 10 second job.

Thanks for the picture and explanation as I was thinking the value or T would be on the input side of the pump, not that output side like shown.

 

[Terry Cox]

Hmm. Our boat has three through hulls that bring sea water in; one that feeds both heat pumps and one each for the main propulsion engine and one for the generator. All three use a sea water strainer to protect the pump impellers from debris. The Little Giant sea water pump for the heat pumps is below the water line and has always self primed. The main engine sea water pump is below the waterline, but the strainer is above, but it has always self primed. The generator sea water pump and strainer are above the water line and it has always self primed, except one time when, after cleaning the strainer, I failed to place the cover back on properly and air leaking past the cover seal prevented it from self priming. Once I found the problem, it was fixed.

 

[thinwater]

Reinstall them correctly, below the waterline with a steady upwards flow (no loops) so that air can clear. Someone did NOT follow the instructions. Strainers should also be below the waterline, with a valve on each side so that they can be easily cleaned and so air can easily be displaced. This is proper design.

Even if you prime the line once, who's to say you won't get air in the line again when pounding into heavy weather?

Fix it correctly. I promise, my bilge is shallower than yours.

 

[sailcapt340]

I also have a T Valve between my strainer and the pump. Simply open the thru hull, then the T Valve for a short time and the system is primed. Should be an easy enough install. Here's a picture, look to the bottom left an you'll see the red handled T Valve, it just empties into the bilge. Hope this helps you out.