Sureflo pump problem

[falconhunter]

I'm having trouble with my fresh water pump. It's a sureflo model 4008-101-A65. The only time I have ever used it was to test it when the rig was new in 2010. We full time and are always hooked to a city water connection. The other day the water was shut off in this park for repairs so I filled my tank 3/4 full and turned the pump on and opened the kitchen faucet. The pump ran but would not prime. There are no shut off valves so thats not the problem. I drained the fresh tank and unhooked the line that goes from the tank to the pump inlet.The line is not plugged from the tank to the pump and screw off strainer screen is clean but I cant even blow through the pump. Is it possible that there is a check valve in the pump that keeps city water from filling the tank that is stuck? Would it hurt to blow about 30 psi of air through the line? I am going to call sureflow Monday but was trying to fix it today but I don't want to do damage with the air pressure to the diaphragms.

 

[Frizlefrak]

OK, let me ensure I read this correctly....you checked for an obstruction from the tank to the pump....did you check for an obstruction between the pump and the T fitting that serves the trailer? 

When you opened the faucet, the pump ran....did it shut off when you closed the faucet as it should? 

Stuck check valve is what I'm thinking too....so you're headed in the right direction.  You might remove the pump and open it up....see if anything looks obvious.

 

[falconhunter]

OK, let me ensure I read this correctly....you checked for an obstruction from the tank to the pump....did you check for an obstruction between the pump and the T fitting that serves the trailer? 

When you opened the faucet, the pump ran....did it shut off when you closed the faucet as it should? 

Stuck check valve is what I'm thinking too....so you're headed in the right direction.  You might remove the pump and open it up....see if anything looks obvious.

There was no difference with the faucet open or closed. The pump runs but water never made it through the pump. I took the line off of the fresh tank and unscrewed the filter screen at the pump and can blow air to the pump with no problem but when I put the filter cap back on(faucets open and city water disconnected) I cannot blow air through the pump.  I know there has to be some sort of check valve built into the pump to keep the city water from filling the fresh tank and it's probably stuck. I was wanting to blow a little air pressure through it before trying to pull the pump and was wanting to know if anyone has done this possibly when winterizing. Where my pump is mounted you would have to be a contortionist to get it unhooked and out although not impossible.

 

[Alfa38User]

To prevent the city water from filling the tank (unless you want it to), there is often a manually operated valve located not to far from the tank inlet . (Mine is skillfully hidden (but clearly marked once you find it) under the kitchen counter. There is also often a check valve on the output of the pump to prevent water from flowing back to the tank when the pump shuts off. It may be part of the pump assembly.

 

[Kamper Dave]

I am of no help. If you can locate the fella that thought mounting these pumps where they cannot be accessed then kick him once for me.
Even when connected to city water our pump will run, prime itself and then shut down because it reached pressure. It sounds as though your pump just isn?t priming itself. If you can blow air from the tank through the fill hose to the pump then that air should be pressurizing the hose and the pump. Do you have a hole in the fill line to the pump or a cracked pump housing? I would think that your fresh water tank would be draining from this leak. Is there water in your fresh water tank?

 

[judway]

I added a check valve in line with the city water supply to make it work. It now works most of the time. I am sure there is a failed check valve some where in my system, but it is hard to get to to fix.

 

[bucks2]

Another reason to "run" everything each month. Pump water, run the furnace and AC, slide the slides, run the genset, open the windows, fill the grey tank and dump it like you do the black tank, open all the doors, turn off the inverter, make the refer run on gas, all those little things that can stop working if they aren't used every now and again.

Ken

 

[Ernie n Tara]

Hi,

Thirty PSI in not likely to hurt anything. The pump is a rubber vane type that is quite tough. In most cases , you could blow thru it while its turning (on even not turning) to free up a check valve. These do operate even with city water turned on.

Ernie

 

[Lou Schneider]

There are 4 one-way flapper valves in the pump (one per chamber).  The usual failure mode is a piece of debris gets stuck under the flapper and wedges one or more valves permanently open.

Replacement valve sets are available.  Here's the data sheet for your pump, showing how it's put together.

I wouldn't recommend blowing air through the pump.  You might pop free the obstruction, but you might also drive it through the rubber diaphram.

If you have a check valve it will be external to the pump itself.  Along with possibly a debris screen to keep crud out of the pump.

Too bad you're not going to Quartzsite.  Shurflow usually has a booth in the Big Tent and they'll repair most of their pumps for free except for some very old models.

 

[kjansen]

I did have to prime one of those pumps after I let it sit a long time even tho they are self priming.  I poured some water in the in take line and then put the line in a bucket of water and it pumped water.  Hooked it back to the tank and it has worked ever since.

 

[Frizlefrak]

Too bad you're not going to Quartzsite.  Shurflow usually has a booth in the Big Tent and they'll repair most of their pumps for free except for some very old models.

Now THAT is very cool  8)

Kudos to them for exceptional service. 

 

[muskoka guy]

my coach has a city water bypass valve located where the city water hooks up. it is meant to keep the city water from filling your water tanks via the pump . when i first got the mh the pump would run and a small amount of water would come out of the taps as long as the pump was turned on. after several days of trying different things i was talking to a friend with a simular mh and he told me about the city water bypass valve. once i found it in the water hook up bay i switched it off city water setting and all was well. hope this helps.

 

[falconhunter]

Update after calling Sureflo today regarding my model 4008-101-A65 pump.

First of all thanks for all the info. My rig does not have a manually operated bypass valve. To prevent the city water from filling the fresh tank there is a built in check valve in the pump. It is located behind the 3 screws where the wires hook up to the pump. The tech at Sureflo told me to remove the 3 screws and behind the plate was a check valve that sometimes get stuck in the closed position. I told him my pump was in a tight spot and he said I could blow 30 psi through the intake side of the pump to try to free it up but he said he hadn't had much luck freeing them up with air pressure but said it was a good place to start. He did say to unscrew the screen filter from the pump first and hook another line to the pump because the screen assembly could be damaged by the air pressure.

I will try the air pressure next chance I get. If I have to pull the pump it might be a while and I will relocate it to a better location for future access.

 

[Jofus64]

Same thing happened to my shur-flo on a trip to NASCAR race last fall. Tried everything possible in the campground. Had to hook one of my camping buddies outside faucet to my city water connection so we would have have water. got the tt home and took the pump out and the diaphram was stuck. I just blew through it with the ole pie hole and problem solved. Maybe I just got lucky.