FW WATER PUMP SURGING

[nornaj]

All
I thought the accumulator was supposed to stop this.
Assumed that there was a build up of air in the accumulator and that there was a relief valve on top.
There may be such a valve, but can't see how it works.
Advice appreciated.
NornaJ

[j]

Jul 6, 2012 1:31:13 GMT nornaj said:

Assumed that there was a build up of air in the accumulator and that there was a relief valve on top.

there is meant to be air in it...

There may be such a valve, but can't see how it works.

If your accumulator is like this red one: www.johnson-pump.com/jpmarine/products/watersystem/accessories.html (bottom of page)

Then the valve is on the top and it is an ordinary car tyre valve (schrader) with a dust cap on it.

specs for the accumulator are on the link above.

I suggest a read of this:
www.ybw.com/forums/showpost.php?s=9644db4728be1d76b737eb27f7c4d578&p=263869&postcount=8

Also, your pumps strainer and tap strainers may be clogged and therefore restricting flow.

[nornaj]

Thank you. 'Tis the red one. Now I see how it is supposed to work.
Strainers are all clear. I guess my next check is to see if there is air remaining in the accumulator bladder.
NornaJ

[cpetku]

The accumumator setup should be similar to components used for a house on a well. As I recall the air pressure in the bladder with no water pressure should be a couple of psi less than the cut in switch pressure. This ensures the pump will start before the accumulator is empty. As mentioned previosly this is adjusted using a simple air pump and guage. If set too high, then the pump wont start untill all of the water is out of the accumulator (0 psig in the water lines).

So to set up the bladder in the accumulator you need to first research the pump to determine the pressure at which it turns on (cut in).

[gdepoerck]

My SO 45DS is 4 years old and I am aware I will have to replace/repair at some point in time the entire salt water pump attached to the front/bottom side of the Yanmar 4JH4TE diesel engine. The pump is attached by 4 bolts, of which one cannot be accessed with a standard wrench as the engine seating block is in the way. Is there an easier way to remove the pump than lift/secure the engine somehow before dismounting the block? My email account is [e-mail] and I am fluent in both French and English. Many thanks to help resolve an issue that must be faced by all 45DS owners.

[nornaj]

The bladder in the Johnson accumulator is ruptured.
Rather than replace the accumulator, it seems that it might be better to replace the Johnson FW pump with a new Variable Speed (VSD) pump that doesn't require an accumulator. Not much extra than a new accumulator, and it appears to have some major advantages (quiet operation for one).
Looking at the Jabsco Sensor Max VSD.
Comments + experience appreciated.
thanks
NornaJ

[ianqv]

If you have the 1ltr Flojet accumulator which does NOT have a valve in the top of it. You can restore the head of air by doing the following - see attached PDF

Hope this helps

Ian

Attachments:

[ianqv]

Hi All.

I would just like to say that because of this thread I fixed the surging problem on my water system!!

Many many thanks

Ian

[ianqv]

still going well!!!

Ian

[Deleted]

Ditto to 'ianqv's post above.
Initially had dificulty getting the accumulator to retain the top up pressure. Exhausting the system pressure then closing the tap before applying pump has fixed the problem.

Re my post 'TAINTED FRESH WATER' - many thanks for all the suggestions.
The filters were clean and pipes thoroughly chemically cleaned three times, no leaks.
Looks like 'davidlym's suggestion to replace the pipes is the next job.

What a very useful website we have; thanks all.
Gerry