Fresh Water Pump

[grewvin1]

Fresh water pump Jabsco, has short run ever 3 min. or so to pressurize. Have checked all connections no water leak or seepage need to know if there is a check valve before the pump to stop water running back into fresh water tank causing drop in pressure at pump?

 

[mr 88]

The check valve is in the pump. You could remove the outlet hose and use a 12" hose that is capped at one end to make sure its the pump and not some tiny leak in the lines . I had a issue with a raw water one and it was a dry rotted bend that was in the bilge area so you never saw the water or miniature leak. I think it was more air than water that escaped.

 

[QBhoy]

Hi there.
Check the intake suction bulb casing where the metal mesh filter sits. If you didn’t drain or open this before winter, they can get a tiny crack there. Hardly noticeable and will still work as normal, but enough to drop the pressure and trigger the pump.

 

[Grub54891]

Do you have a water heater? I serviced one that was doing the same thing. Took awhile to find it, but finally found the water heater heat exchanger had a hole in it, allowing the fresh water to leak down.

 

[QBhoy]

Do you have a water heater? I serviced one that was doing the same thing. Took awhile to find it, but finally found the water heater heat exchanger had a hole in it, allowing the fresh water to leak down.

Excellent point. Another usual suspect. Other side effect of that is the domestic and engine cooling water getting mixed with each other, haha.

 

[Grub54891]

Excellent point. Another usual suspect. Other side effect of that is the domestic and engine cooling water getting mixed with each other, haha.

Yes, that probably happens. After trying to figure it out, I was standing on the aft deck, wondering what was wrong, I had replaced the complete pump already, capped the line and then it would be ok. Hook back up and no leaks, but pump would kick in again. As I was standing there, I saw a small trickle of water coming from the exhaust outlet, inboard boat. Ahah! There it is! Bypass water heater and issue fixed.