Surflow pump issues

Hi All, 

I have a surflow pump that sounds and looks like it's working but doesn't draw any water through it. Any ideas what's wrong before I have to buy a new pump ? 

No doubt it will be an airlock, possibly caused by the tank running really low or dry and causing air to get into feed hose disconnect hose from your hose reel and turn flow up to 50% until water starts coming through then whack on full until the water stops make a spluttering sound.

Phil Payne Window Cleaning said:

Hi All, 

I have a surflow pump that sounds and looks like it's working but doesn't draw any water through it. Any ideas what's wrong before I have to buy a new pump ? 

Click to expand...

You really need to give the forum a bit more detail about your system.

For example; where the pump is situated with regard to the tank.

Have you a flat or upright tank? 

Is it a van mount or a trolley system?

What connectors have been used on the pipe from your tank to the pump and what connector are you using at the pump?

Have you got a strainer/filter between the tank and the pump?

Have you tried sucking water through the pump from a hose connected at a van port of similar place? Cn you then blow air the other way?

Is this a problem that has just suddenly happened or is it something you experience often? If its happened before how did you overcome it? When the problem first occurred how much water did you have in your tank?

We were taught to ask questions when trying to trouble shoot a problem. The first presumption is that the system was working prior to the problem without issue. Then the problem started. So what changed when the problem started? 

Lets take @Iron Giant's suggestion that you have an air lock from running your tank low. If there was no problem prior to this then @Iron Gianthas identified the source of the problem and a solution. Now you have found you can suck water into your pump but you can also blow it back the other way as well. So now you know the source of the problem could be inside the pump. If you ran your tank empty you could also have sucked some muck into the pump from the bottom of the tank. Inside the pump is a tiny non return valve with a fine trigger spring. Either the spring has broken or there is a bit of muck on the seat of that valve plate. By sucking water through the pump you might be able to clear it.

In the nearly 14 years we have been wfp we have never had a mechanical problem with a Shurflo pump. We fitted the Shurflo pump above the top of the tank in my son's van. A while back he sucked his system dry. Initially it takes a bit of time to suck the water up the tube to the pump but once it gets to the pump its 'away'.

On each of our pumps we have a Shurflo filter with wingnuts. The seat of the male thread onto the pump and the filter are coned shaped. We found we need to nip that nut up a fractional more with a spanner. Just a tad as we don't want to strip the threads. This ensures the pump doesn't suck in air rather than sucking water from the tank.