Water pump problems--Shurflo 4008

[dr_e_squared]

I've read a lot of forum posts about the problems with Shurflo water pumps, but none exactly like the problem I'm having...hoping someone can chime in with helpful hints! We have a 2013 Georgetown 335 (bought it used with very little miles on it). Since we have had it, whenever I hook up to city water, it doesn't take long until water is running out of the overflow drain. I've read many posts about the siphoning effect and thought maybe that was my problem. But then...

I turned the city water off on the last trip and just pumped from my fresh water tank, since it was full. The pump ran intermittently not only on demand, but about every 2-4 mins when not demanding. Then all of a sudden, the pump got very loud. When I opened the access panel, several screws had backed out of the upper assembly and were laying on the floor. I figured I had found the problem, so I tightened all of the screws, except one that had sheered off. ( I even used a clamp on that corner to see what effect it would have). No matter how tight, when I turn the pump on, the vibration backs the screws out and eventually the upper assembly separates.

From previous posts I read, I am guessing the pump is the source of all my water problems. The check valve that is supposed to keep the city water out of the fresh water tank, the sheered off screw, the separating of the assemblies. My question is this: Is there another solution besides buying another pump? I've read there are some rebuild kits, but for $60 on Amazon, I'm thinking I'll bite the bullet and buy a new one. Any thoughts or comments on what I may be over looking would truly be appreciated!

[4B11T]

You could buy one of these off off Amazon SHURFLO 94-800-00 Model 4008 Complete Housing

[5picker]

Sometimes you can get away fixing things but from what you've described, my advice is replace the pump.

[wvphil]

This is a common problem with the pumps. I had same issue. Quick cheap fix is buy a check valve at lowes or home depot and install on the line going from tank to pump. Ie attach to input or output side of pump then connect your plastic line back to the valve. The valve will have an arrow pointing to the direction water flows so you dont need to be a experienced plumber to hook it up. Use some teflon paste or tape on your threads of fittings to prevent any leaks. The in line check valve keeps water from flowing back to your tank when hooked to city water. I attached mine on input side of pump but can be used on either input or output side. Goal is to keep the water from flowing back to your tank which overfills and causes water to run out of overflow on fresh water tank. The check valve serves same purpose as valve built into the pump and are a very common fail on the surflo pumps. I did this mod around 20 months ago and no problems. Pump still pumps same as it always did with good pressure when not hooked to city water and pumping from fresh water tank.

[dr_e_squared]

Thanks! Since the current housing has sheared off screws, I decided to buy a new pump. But I will definitely invest in the check valve as it sounds like I may be faced with this issue again!

[martyleach]

I have the same pump. It has recently started filling up my on board freshwater tank and overflowing it when connected to external water source. I was told that my pump head was bad as it should act as a check valve. So instead of buying a new pump head I just installed a check valve (get a good one, not the cheapo plastic) on the input hose from the water tank. Check valve $10 and 2 barbed plastic fittings with 2 hose clamps. Works great and I now feel comfortable that I will never mix waters again.

Actually, I am still under warranty but can't get it for service for 2 months and we are leaving with the trailer for 4 weeks beforehand. So I had to make a fix.

[martyleach]

Originally Posted by wvphil

This is a common problem with the pumps. I had same issue. Quick cheap fix is buy a check valve at lowes or home depot and install on the line going from tank to pump. Ie attach to input or output side of pump then connect your plastic line back to the valve. The valve will have an arrow pointing to the direction water flows so you dont need to be a experienced plumber to hook it up. Use some teflon paste or tape on your threads of fittings to prevent any leaks. The in line check valve keeps water from flowing back to your tank when hooked to city water. I attached mine on input side of pump but can be used on either input or output side. Goal is to keep the water from flowing back to your tank which overfills and causes water to run out of overflow on fresh water tank. The check valve serves same purpose as valve built into the pump and are a very common fail on the surflo pumps. I did this mod around 20 months ago and no problems. Pump still pumps same as it always did with good pressure when not hooked to city water and pumping from fresh water tank.

It really must be attached to the input side of the pump. If it is on the output side of the pump, the pump will cycle as the water seeps backwards through the pump. Trust me, I did it because the access was better. Then I did it again....