Jabsco pump pulsation dampener

[Icarus]

Hi,
I have this ongoing annoying problem with my 12V Jabsco belt driven fresh water pressure pump 36800 series.


Pump works fine for about 6 to 8 month or so then it starts cycling, generally runs uneven.
Taking the thing apart I noticed the large pulsation dampener got severely distorted and torn.
I buy a replacement and all is fine for another 8 month or so, same problem, the dampener is deformed and partly torn again, pump runs like crap again.

One would think the dampener would last at least 2 years or so.
Its getting rather expensive to service the pump every 6 to 8 month.


Pressure is 35 to 40 psi, there is an accumulator fitted as well.


Has anyone anyone who has a belt driven Jabsco pump, or is familiar with it, come across this issue ?


I guess the only remedy is to chuck the thing and buy a different pump (quad diaphragm), reduce pressure setting?


Cheers

[stormalong]

I have a Jabsco 36950, probably very similar to yours. This is a common issue but my dampers last for years. Two suggestions.

1) Get a 20 psi switch. You do not need 40 psi unless your boat is multi story.

2) Turn off the pump and release the pressure when you are away from the boat for a while.

I know a lot of people curse these pumps but newer pumps seem to be even worse. I have two of these pumps, one standing by as a spare. I can't remember how long ago I had to do a swap. I also have a large supply of rebuild parts given to me by someone that went to a more modern pump.

One additional suggestion. Get an automotive headlight relay and socket. Wire the pressure switch to control the relay and the relay to run the motor. The automotive relays are much cheaper than the pressure switches and the socket makes changing the relay easy. Carry a spare relay.

[Icarus]

Originally Posted by stormalong

I have a Jabsco 36950, probably very similar to yours. This is a common issue but my dampers last for years. Two suggestions.

1) Get a 20 psi switch. You do not need 40 psi unless your boat is multi story.

2) Turn off the pump and release the pressure when you are away from the boat for a while.

I know a lot of people curse these pumps but newer pumps seem to be even worse. I have two of these pumps, one standing by as a spare. I can't remember how long ago I had to do a swap. I also have a large supply of rebuild parts given to me by someone that went to a more modern pump.

One additional suggestion. Get an automotive headlight relay and socket. Wire the pressure switch to control the relay and the relay to run the motor. The automotive relays are much cheaper than the pressure switches and the socket makes changing the relay easy. Carry a spare relay.

Thanks for your input.
Yeah, I was thinking about reducing the pressure and see how it goes, fitting a relay makes sense.
Cbeers