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Topic: Shurflow 4008 change to Shurflow 4048 (Read 1009 times) previous topic - next topic

Shurflow 4008 change to Shurflow 4048

I am anticipating changing out my shurflow 4008 to a shurflow 4048 for better water pressure and water flow. The only change I see is the fuse size for the 4008 is 7.5 amp compared to a 15 amp for the 4048.  Can I presume the wiring would be ok for this and I just install a 15 amp fuse in place of the 7.5? Everything else looks the same...Can anyone confirm this?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Shurflow 4008 change to Shurflow 4048

Reply #1 –
We have used both Shurflo 4008 & 4048 and have switched back & forth and like them both and find them similar for our plumbing.

Are you sure you have a 7.5 fuse as you may already have a 15 amp fuse on the water pump latching relay circuit?  We have not had to change fuse size.

Both models operate similar with an internal adjustable pressure-controlled bypass spring valve.  Pumps have a constant speed motor and when pump output volume exceeds faucet demand, pump may stay running with excess water flow bypassed to input side of pump. This design works very well, especially for low water flows, and eliminates the electronic circuits needed for variable speed pumps.

We did find some improvement by adding a small Shurflo plastic accumulator on pump output hose (½" male thread in & out, bought from Amazon).

Re: Shurflow 4008 change to Shurflow 4048

Reply #2 –
Where is the latching relay for the water pump? And to be honest, have never looked at the pump. It may have the accumulator already?
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Shurflow 4008 change to Shurflow 4048

Reply #3 –
Water pump circuit breaker & latching relay on our coach is on rear street side big bay wall under a white fiberglass cover held in place with two wing nuts.

Re: Shurflow 4008 change to Shurflow 4048

Reply #4 –
Thanks..I will check the relay size.
Peter
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Shurflow 4008 change to Shurflow 4048

Reply #5 –
Peter, it is not the relay but the circuit breaker that powers the water pump that you need to check. You white panel might be on the drivers side on the rear of one of the basement section dividers. 

The circuit breakers are on the left behind the panel. Right hand bottom should be for the water pump/fill valve.  Look to see if you have this drawing for your coach.  Things change from year to year but this should be not be one of them.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Shurflow 4008 change to Shurflow 4048

Reply #6 –
Hi Roger,
Yes it is the same, and it is a 15 amp breaker.
Funny when I went to look at the water pump (finally took of the covers to view) the water pump has a 20 amp fuse inline for the power (see photo)  Maybe I should change that out to a 15 amp as well???

 I also was wondering about the accumulator but it already has one.  (see pics)

Looks like an easy swap, but there is no water tank turnoff... Can I turn the lever below the accumulator off to stop the flow? (grey valve)
In looking, the PO has swapped the original out with the 4008. Look closely you will see the line from the tank is an adhoc line that is looped cause the line to the water pump does not match up
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Shurflow 4008 change to Shurflow 4048

Reply #7 –
Peter, I would leave the 15 amp circuit breaker as is unless you have problems with it opening when the pump is running. The wire size FT used is probably OK for a 20 amp CB if you need to change it.

My coach has a valve between the tank and the pump. If you are in there changing stuff that might be a good addition.  Otherwise I guess you need to drain the tank on one side and the cold water lines on the other to swap the pump.

The expansion tank is connected to a T in the cold water side after the pump.  The valve there isolates the accumulator tank so it can be removed and replaced or removed from service.  The pressure in the accumulator tank should be a couple psi below the cut in pressure (pressure when it starts to pump) of the pump.  Turn the pump off an open a cold water valve and let the water run till it stops so there is little or no pressure left in the system then check the tank pressure.  It should say on the pump what the cut in pressure is and it may say what the accumulator tank pressure should be.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Shurflow 4008 change to Shurflow 4048

Reply #8 –
Thanks Roger.
at this time I am not going to install a cutoff valve (another tie project) so I will drain the tank and cold water lines. If I read your post correctly there is nothing more I have to do with the accumulator when I replace the water pump then unless I want to replace the accumulator. yes?
And I think I will replace the fuse with a 15 amp one...
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Shurflow 4008 change to Shurflow 4048

Reply #9 –
Be prepared for water leakage from the accumulator and plumbing ends.  Maybe a few towels, a couple paper towels are likely not enough.

The CB protects everything down stream.  A short will trip the CB.  If the pump suffers an electrical failure the CB will trip before the 20 amp fuse.  If they are both 15 Amp, the fuse will probably go first, depends on fuse and CB types.
Roger Engdahl and Susan Green
2001 U320 3610 #5879 (Home2) - 2014 Jeep Cherokee or 2018 F150
Hastings, MN

Re: Shurflow 4008 change to Shurflow 4048

Reply #10 –
Every coach should have a small ball valve on water pump input and output hose so pump can be easily removed without draining fresh water tank and water manifold.

And flexible long hoses should be used if there is room. In our coach, we do not fasten pump down and if we need to examine pump, we can move it out in the open, even without removing hoses.

Re: Shurflow 4008 change to Shurflow 4048

Reply #11 –
Quote from: Barry & Cindy –
Every coach should have a small ball valve on water pump input and output hose so pump can be easily removed without draining fresh water tank and water manifold.

And flexible long hoses should be used if there is room. In our coach, we do not fasten pump down and if we need to examine pump, we can move it out in the open, even without removing hoses.

You will be well served by following Barry's suggestions.  I have added the shut off's and now I can change out the pump, in a few minutes, with no water loss.
Dave Cobb
Buckhorn Lake Resort The Club, #6202, Kerrville TX
check the map.  I do rent it out when I am traveling!
2001, U320, 36' #5887, in Kerrville, FT Club #17006, (7/23 to present)
2024 Jeep Grand Cherokee L, Summit, white
EX: 98 U295, 36' #5219, (mid door), (4/13-10/23)
EX: 93 U225, 36' (4/11 to 4/13)

Re: Shurflow 4008 change to Shurflow 4048

Reply #12 –
any suggestions for a shut off valve??
Peter
Peter    Alberta Canada
'98 U320 40'  Build 5359 M11 450 HP, Aqua hot, Blu Ox

Re: Shurflow 4008 change to Shurflow 4048

Reply #14 –
Quote from: dicksop –
Any suggestions for a shut off valve??
I used SharkBite 1/2" push-connect quarter turn brass valves.  Work great with the OEM grey plastic water pipe.

https://www.lowes.com/pd/SharkBite-Brass-1-2-in-Push-to-Connect-Ball-Valve/1000182579

I second Barry's recommendation for flex hoses in and out of water pump.

Amazon.com: SHURFLO 94-591-01 Pump Silencing Kit : Automotive

A water filter (strainer) on the pump inlet is also a good idea.

Amazon.com: SHURFLO (255-313) 1/2" Twist-On Pipe Strainer : Tools & Home...

As an Amazon Associate Foretravel Owners' Forum earns from qualifying purchases.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"
 

Re: Shurflow 4008 change to Shurflow 4048

Reply #15 –
Here is another option for the flex hoses ($34 shipped). I'll be happy if it reduces some of the vibration noise.
http://www.etrailer.com/RV-Fresh-Water/Valterra/P23512PB.html
Bruce & Linda
2004 U295, Build # 6268, ISL400 CAPS
2016 Ford Explorer Sport or 1985 Jeep CJ7