Salt water wash down

[Yannis]

My salt wash is shot. It engages, it works for a few seconds (approx 10-20) and then it stops by dropping the switch on the main board.
You lift the switch, it works again and it stops the same way. My electrician says that if he tries to unscrew the screws on the body of the pump they will brake because they're alu on some other metal and they've corroded ....together!

Bottom line : Do I buy a 60 -70 euro one and probably change it every year OR do I buy an expensive one for say 150-200 euros to keep; salt can't guarantee you anything though... Or do I open and fix the existing one. What is there to fix inside? Lubricate? Change any o rings ? D@mn !!

[Charlie J]

yannis
I use the jabsco super pro blaster putting out 5.5 gpm
i use it for wash down and live well with a y valve
i normally get about 5 years out of them, cost appox $ 200 us
dosent pay to pull them apart

[Yannis]

Charlie,

What do you do to them to last 5 years? Do you rinse them after every season? Even rinsing is a problem, because each time you want to rinse you probably have to disconnect the through hull feed and temporarily attach a fresh water bucket, work it for a few liters and reattach... Is this what one has to do?

[Charlie J]

yannis
I don't do anything as far as flushing is concerned
only run anti freeze thru it for winterizing when layed up
I find the cheap units don't last to long
have had a good run with theses pro blaster

[Charlie J]

http://www.defender.com/product.jsp?pat ... id=2127613

correction shurflow

[Yannis]

Thank you Charlie.
Do you know if they're the rotating (impeller) or the pulsating(?) type ?
Thanks.

[Charlie J]

don't know

[CaptPatrick]

These types of pumps operate by pumping water through 4 small round valves. Each valve increases the pressure from the previous valve ending up with the final discharge pressure. They are quiet and very dependable. Basically a type of pulsating pump that will need a small pressure tank to smooth out the water flow if a pulsating flow is not wanted...

[Tony Meola]

Yannis

For a salt water wash down I use a Jabsco vane pump. If you mount it so that the head points down, it may last longer. I have actually had pretty good luck with them. Pushed 7 to 8 years. What usually makes them go bad is if you have any leaks and the head points up, then the salt water runs down the pump and kills it.

[Yannis]

Thank you Captain.

Tony, interesting to know.
Not sure tho what a vane pump is ! Looked it up but became no smarter...

[Navatech]

Not sure tho what a vane pump is ! Looked it up but became no smarter...

There are different types of pumps... They can be classified primarily into two classes:

1. Variable volume (sometimes also called positive suction pumps) such as:
   • Piston
   • Screw (I won't mention these any further but think Archimedes)
   • Membrane
   • Impeller
   • Vane
2. Centrifugal (sometimes also called flow pumps)

Piston and membrane pumps are pretty similar in that they have variable volumes (reciprocating piston or membrane going up and down) and they require check valves on the inlet and outlet to function properly...

Impeler and vane pumps are somewhat similar to centrifugal pumps in that their main pumping element rotates but they differ from the centrifugal pumps in that their main pumping element actually does create a variable volume... The impeller (a.k.a. Jabsco) pump has a rubber impeller which due to the housing in which it rotates bends the rubber vanes thereby creating the variable volume... Vane pumps are similar in concept but their vanes telescope instead of bend thereby creating the variable volume... Due to their construction impeller and vane pumps do not require check valves on the inlet and outlet...

Variable volume pumps create a positive suction (vacuum) and are self priming...

Piston and membrane pumps do not require internal lubrication (in the form of the liquid pumped) and can therefore run "dry" for extended periods... Impeller and vane pumps (the first more so then the latter) require internal lubrication and can NOT run dry for any length of time...

Centrifugal pumps basically pump liquid by putting it in motion (hence flow pumps) and do not create a positive suction... They are therefore considered non self priming... They do not require internal lubrication and can therefore run "dry" for extended periods...

[lobsta1]

Yannis,
Don't know about this particular set up, but I have used Johnson domestic water pumps for 25 years with excellent results.
Al

http://www.marinepartssource.com/newdet ... n+Pump+Kit

[Tony Meola]

I usually consider a vane and impellar pump one in the same.

[Charlie J]

lobsta
that's a good price

[Rawleigh]

I mount all of my pumps head down to protect the motor. I also set up a three way manifold at the inlet of mine so I have hot and cold salt water as well as cold freshwater washdown. Hot saltwater is drawn off the heat exchanger discharge hose. It really helps cleaning up fish guts, etc.

[Yannis]

Nav, one could perhaps assume that you're a ....mechanic of some sort !!

Thank you all for your input.

[Yannis]

Lobsta,

That's the one I have and has gone bad on me.
However I have no idea how long its been there already; when I bought the boat it was there, so I assume more than 4-5 years anyway.

[Navatech]

Nav, one could perhaps assume that you're a ....mechanic of some sort !!

My original training was as a marine engineer... A.k.a. grease monkey...

Thank you all for your input.

Always welcome...

[Yannis]

Rawleigh,

What do you mean you install the pump upside down?
I just bought a shurflo from amazon and thought to clear this up before I install it . Thanks.

[Rawleigh]

Pump part down, electric motor up. Sorry I wasn't more clear.

[Yannis]

Thanks.

Why did I have the impression that this is the right way and not the upside down one !

[Tony Meola]

Thanks.

Why did I have the impression that this is the right way and not the upside down one !

Probably because you do not follow the logic of most people who are not real good mechanics or boaters. They would put the motor on the bottom and the dam thing is rusted in a year.