In-Line Water Strainer Problem?

[bobk]

Recently the Shurflo Extreem fresh water pump has been erratic, sometimes not building up pressure and not shutting down. In looking for the cause I noticed the water level in the in-line strainer before the pump is much lower than normal (compare water level lower right of strainer to stain that represents previous level). This is a PITA to access, so before I get into it I'd appreciate some thoughts on why the level is down and and if these things can clog. The screen looks clear. Obstruction?

Bobk

 

[MikeP]

The pump could be bad but I'd look first for an air leak on the suction side of the water system.

 

[GJH]

Is that picture with no water running? If so, that could be our old friend the check valve letting drain back into the tank. There should be at least one between that strainer and the pump.

 

[Beckytek]

Ditto to what Mike said about the air leak. If there is a leak on the inlet side, the pump won't build pressure so it won't shut off if it doesn't reach the high pressure set point. Make sure you have a gasket in the strainer and it is on tight. check all connections to pump.

 

[bobk]

Is that picture with no water running? If so, that could be our old friend the check valve letting drain back into the tank. There should be at least one between that strainer and the pump.

The picture is after shutdown (45psi). When pumping there is a swirl of water that appears higher, but it drops immediately to this level when it shuts down. Seems too fast for a drain back due to a slow leak...... but maybe. But it sure seems like air is getting in. That's the easy place to start.

Bobk

 

[Pascal]

Is it the smart sensor pro blaster shurflo?

I just installed one 3 weeks ago and it s been acting up when voltage changes (after engine start or charger varies voltage) I should have know having had issues a few years ago but infigured by now they d have worked out the bugs

Air can stay trapped in the strainer when installed upside down I don't think that s your problem

How old is the pump? When the diaphragm wears and eventuLly gets a hole water will push into the pump motor (thru have no weep holes) giving the symptoms you describe. Believe it or not the motor will keep running for a while with water inside!

 

[bobk]

Is it the smart sensor pro blaster shurflo?

I just installed one 3 weeks ago and it s been acting up when voltage changes (after engine start or charger varies voltage) I should have know having had issues a few years ago but infigured by now they d have worked out the bugs

Air can stay trapped in the strainer when installed upside down I don't think that s your problem

How old is the pump? When the diaphragm wears and eventuLly gets a hole water will push into the pump motor (thru have no weep holes) giving the symptoms you describe. Believe it or not the motor will keep running for a while with water inside!

Pascal.

I remember your earlier posts on the topic. This pump has been in service about four years and has had no issue until this. It still builds pressure and holds it. I don't see a difference with voltage changes. It is a 12 volt pump. It is a Smart Sensor Extreeme Series. I think the Pro Blaster is a wash down pump.

Would you expect it to hold pressure if there were a hole in the diaphragm?

Bobk

 

[Pascal]

You re right the pro blaster is the conventional pump, usable as the house pump too

If you spend a lot of time aboard 4 years is about the life span for these according to specs I got from shurflo obviously those who don't use the boat year round or dont live aboard get much more time...

When the diaph failed on mine, it was holding pressure just taking longer to shut down with lower pressure/flow til it could build enough

The one i replaced leaving new England was 3 1/2 years old and just no longer giving enough flow. Year round use although a head hunter is often used at the dock

Finally if there was a problem with the pump pulling air, you d have air coming out of the faucet and spitting

I bet on the pump...

 

[bobk]

You re right the pro blaster is the conventional pump, usable as the house pump too

If you spend a lot of time aboard 4 years is about the life span for these according to specs I got from shurflo obviously those who don't use the boat year round or dont live aboard get much more time...

When the diaph failed on mine, it was holding pressure just taking longer to shut down with lower pressure/flow til it could build enough

The one i replaced leaving new England was 3 1/2 years old and just no longer giving enough flow. Year round use although a head hunter is often used at the dock

Finally if there was a problem with the pump pulling air, you d have air coming out of the faucet and spitting

I bet on the pump...

We live aboard about 6 months per year and do some southern cruising as well, so it has plenty of use.

I have been getting a bit of spitting recently. When the pump is ready to go, do you replace the valve assembly as well as the diaphram assembly? Any idea of the cost? Worst Marine is quite a way from here.

Bobk

 

[Pascal]

The diaphragm is called Drive Assembly, it s about $75 or so

That should be the only part you need but i hate to throw parts at problem Open it up first to check the motor, valve etc

If you only have one pump, I d buy a new one and then repair this one as a spare

Spitting is usually a sign of air in the system. Btw with those pumps you don't need a check valve

 

[bobk]

This job finally made it to the top of the list. When the tank is full, it works fine, when the tank is at 3/4 I found a bit of air getting into the hose connection at the pick up tube. This may not be original. I pulled the pickup tube and it is a copper pipe soldered to the male end of a street ellbow. That was solid. The female side was fitted with a rough bronze cast hose barb. This was the leak source. I filed it smooth and fitted a new clear reinforced hose and it works great. It was indeed an air leak!

Thanks for the guidance. Now I have to get the Hart Tank Tender to work right on this tank.

Bobk
Chateau de Mer
lying Port St. Lucie