Fresh Water System Dilemma!!

[sailorboy1]

Originally Posted by jump12k

I thought the water pump did have a pressure shut off valve within...

Where should I look for this "suction check valve back"?...Or the "Pressure switch" you mentioned that is not in the water pump?

They normally are part of the pump

[jump12k]

SAILORBOY 1....Okay...but I just replaced the almost new pump with a brand new one and the new one does the same thing...

[capt.rob]

First I was in plumbing for over 20 years 15 as a service tec.I think you may have more than 1 issue, first If you are getting air bubbles out of system it is most likey caused from a leak in the suction side of the plumbing from tank to to pump. This will also make pump run continuisly besause it's sucking air instead of water. May be leak around hose fittings or valve handle, If it's not a ball valve first check packing nut around valve stem. It's the most common place for a leak like that. Air is far less dence than water and air can be sucked in without water leaking out. A far as the no water coming from tap sounds like a clog in areator, faucet or pipeing to it from pump. If it's hose there is many things they can do from interior desinegration and delaminating or colapsing of interior wall, Also washers in faucets or old valves can come apart and clog it up. If it is easy to disconect and re connect from faucet and pump do it then try blowing through the line from fucet to pump connection ( put pump end in a jar) and see what comes out. same with faucet. If cloged may need to replace supply pipeing, valves or disasemble them to remove cloged particles. Some hoses like the blue ones with white interior are notorious for interior delamination pressure gets on wrong side of thin inner wall and colapses the liner against itself. Good luck!

[sailorboy1]

Originally Posted by jump12k

SAILORBOY 1....Okay...but I just replaced the almost new pump with a brand new one and the new one does the same thing...

yet you don't seem to know anything about it

Was it an automatic pump? What type of pump is it?

Are you sure the water tank is full, the suction valve is open, and that the suction pick-up line is clear?

Is the suction strainer clean? Is the cap on it tight?. Are the suction fittings tight?

To me the pump not cycling off (assuming it is an automatic pump) suggests a pump suction/water tank issue.

[Mike Banks]

It sounds to me as though someone has placed a non-reversing valve in the sink circuit and put it in the wrong way around.

Failing that, you may have a kink in one of your hoses--a copper line crushed somewhere. or if you hear the pump running when the tap is turned on and not much water is coming out---check your bilges for water because that sounds like a leaking pipe.

[jump12k]

Thanks Capt. rob and Mike Banks....
I will look into these issues you suggested... I think I'll try replacing the valve that switches starboard to port tanks....after all I think it is like 37 years old and seems a little worn. It's an old brass valve lever...