Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 12, 2025 ...

pressure regulator/ water pump

October 01, 2015, 08:26:53 am

Good day to everyone.Was outside last night playing with the coach again.Since we have purchased it a short time ago, we have had a problem with the water while dry camping.The water pump runs fine but after approx. 3 to 4 minutes it will start to cavitate loose pressure and the green light in the coach will go on and off without touching it.Bonnie included a brand new water pump with the coach.It only took 15 minutes to change.It made no difference.In with the water punp is what looks to be a pressure regulator.There also looks to be an eye that the water flows by.The filter on the pump is clean and the filter under the sink looks good.(I have a new one to replace it with if need be), any thoughts would help.If I shut off the pump after it starts acting up for about 1 minute, it then seems to reset and work fine again for 3 to 4 minutes. We actually did not notice it until Brenda took a shower.As always thanks Bob

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Re: pressure regulator/ water pump

Reply #1 – October 01, 2015, 09:53:44 am

Green light going on and off could be intermittent power. Might check all 12vdc connections? 

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Re: pressure regulator/ water pump

Reply #2 – October 01, 2015, 10:10:54 am

Lots of stuff going on here.
Filter under the sink is not part of this issue.  "Cavitating" pump is either water starved or getting air in the line.  If you have an acumulator tank the pump should not run continuously or for 3-4 minutes before pressure builds up and the pump shuts off. Make sure there is no obstruction in the incoming water line. Make sure you don't have a broken water line.

Why the switch light goes off is likely something else again.  Any of the pump on/off switches enable/disable a relay that supplies power to the pump and to all of the pump switch green indicator lights.  The pressure switch in the pump turns the pump on when pressure is below a set level and off when the pressure is high enough.  If your green lights are going off then there is no power to the pump.  It might be a relay problem.

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Reply #3 – October 01, 2015, 10:33:07 am

Ok I will check the relay and the power. when I speak of running for 3 or 4 minutes I mean with the kitchen sink handle wide open.
as soon as I shut off the faucet the water pump stops. The system seems to be tight , because the water pump will not run if it is not called for. so I do not seem to have any leaks in the system. The regulator right behind the water pump has a 4 screw type of diaphragm, which has an adjustment with a knob handle as well as a brass screw that seems to turn the pump on and off if I adjust it.I believe that this diaphragm may be an issue. The pump runs fine , but if you leave the water running i.e. the shower on it starts to crap out and pulsate after approx. 3 minutes. Small hand wash ups or dish cleaning not an issue.Bob 

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Re: pressure regulator/ water pump

Reply #4 – October 01, 2015, 10:36:53 am

The pump should put out more water than the faucet flow.  Do you have an acumulator tank?  Might be a problem there.

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Re: pressure regulator/ water pump

Reply #5 – October 01, 2015, 11:23:20 am

Do you have air coming out the faucet when this occurs, or is it just that the flow diminishes?

To test the accumulator:

Shut off water pump.

Open faucet to relieve all pressure.

Remove the cap on the accumulator schrader valve

With a small screwdriver momentarily depress the valve-- if air comes out, all is good-- proceed.  If water comes out, the bladder is ruptured and you need to replace the accumulator.

Check pressure (schrader valve, just like a tire, so you can use your tire pressure gauge)

Proper PSI is 2 PSI less than pump cut in PSI

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Reply #6 – October 01, 2015, 01:16:37 pm

I'm having an issue too.  My pump will run and run but if I turn the switch off and on and off and on I can sometimes get it to stop.  I did this yesterday and left the system pressurized all day and when I turned the switch back on the pump did not come on so I'm sure I have no leak.  Not seeing any water either.  The water pressure when using the pump seems to be lower than what it used to be.  Does this sound like a pump problem or an accumulator problem?  Also, how do I know what the pump cut in pressure should be?  Brett, do you remember what yours was on the 240?  Another stupid question.  Where is the pump and accumulator tank and how do I access it?  Where was yours Brett?

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Re: pressure regulator/ water pump

Reply #7 – October 01, 2015, 01:38:05 pm

Dwayne,

Look under the sofa for both pump and accumulator.

Fresh water accumulator pressure=23PSI (2 PSI less than pump cut in pressure per Shurflo)

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Reply #8 – October 02, 2015, 02:22:29 pm

What are the symptoms of pump failure vs. accumulator failure?

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Reply #9 – October 02, 2015, 03:35:07 pm

Start with the accumulator, as it is easy to diagnose.

Remove the cap to the schraeder valve.  Just touch the center pin with a small screwdriver.  If air comes out, you are good to proceed.  If water comes out, the diaphragm is bad and it will need to be replaced.  Most box stores have them.  If air comes out, with the water pump off and system depressurized (open a faucet), set pressure (bicycle pump works fine) to 23 PSI.

The pump can fail in a number of ways, but they are pretty reliable.  Let us know the symptoms AFTER you check the accumulator.

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Reply #10 – October 02, 2015, 11:04:23 pm

Water comes out. I've never worked on one of these...what's the procedure? 

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Reply #11 – October 03, 2015, 08:56:32 am

Measure the diameter of the accumulator (at least that is my recollection of the attachment method on your coach). You can look on-line or in box stores for replacements that will fit.  You do want one with a diaphragm in it. You may need a reducer as the threads on the plumbing may be smaller than those on the new tank.

Safest to drain water from the tank before replacing. Put a towel under it.  Undo what is securing it to the floor. Unscrew it from the plumbing connection. 

Biggest problem is working under the sofa-- consider removing a couple of bolts and using a board to hold the sofa bottom up out of the way.

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Re: pressure regulator/ water pump

Reply #12 – October 03, 2015, 10:59:56 am

Difficult to see everything but it looks like tank is held by two large hose claps. I see only one water connection on the opposite end from the air valve. I expected two.

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Reply #13 – October 03, 2015, 02:27:18 pm

Nope, just one.  And the large hose clamps I why I said you would be shopping by diameter.

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Reply #14 – October 03, 2015, 02:28:57 pm

The tank only has and needs one connection.  All it is doing is creating a head pressure in the water line, to force water out of any open valve you open somewhere.  The tank is in the system to keep the pump from switching on and off all the time as the pressure drops.  The system will work without the tank, but you will hear the pump going on and off all the time.  Cheaper coaches and lots of trailer and boat systems work without tanks.  Tanks can be added to almost any system to reduce the short cycle pump noise.

If you are only having problems in the shower, check the hose connection at the wall to hose.  Next check the hose to the shower handle connections.  Both have filters or screens that can become clogged.  I have cleaned both end connections and got better water flow.

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