Water Pressure Dropping Intermittently

[psychfeld]

Hi All!

I have a Aqua Jet Uno (Johnson Pump) version 5.2 on my Lagoon 420. This is my first year on this boat and it's all new to me.

Recently the water pressure in my boat has been dropping off while there is water in the tank. After a delay of a few seconds the pressure returns, however I realize I'm probably on borrowed time before it stops.

The troubleshooting guide in the manual says to clean the valves but I've got no clue what they mean by valves and the part diagram does not indicate any valve on the parts diagram.

I thought the clear plastic strainer should be opened and cleaned however it doesn't want to come off with hand twist and I'm wondering if I should use a mega pliers to twist it off and clean the strainer.

When it's running ok I notice there's some modest heat built up on the electrical connections which I assume is normal but I'm wondering if I should check all the electrical connections and get them lubed and cleaned.

When the unit stops working, it does eventually come back on, on it's own. This has me thinking it's restricted flow that's the problem - but I'm wanting to confirm that checking the strainer should be done, and does anyone have an idea of what the manual refers to as "valves"?

Any ideas would be helpful.

Thanks everyone!

Rob

[DeepFrz]

I'm just guessing because I haven't seen that pump but it looks like there is a clip on item 51 that holds the inlet pipe into the filter housing. That clip should allow you to remove the inlet pipe. Maybe then you can turn the end cap off to clean the filter. If you use pliers use gentle force.

The valves are items 6 on page 40. That whole exploded view is basically of the valve/pump assembly.

I would recommend you contact your local distributor and get their advice. If it is the filter it might be best to install an easily serviced water filter ahead of the pump to prevent problems in the future.

I hope this helps.

[Lepke]

Diaphragm pumps don't last long with heavy use. Both the diaphragms and valves wear quickly, especially water with any sediment in it. I may be fussy, but when I install something I expect it to last many years. I have a shop with about a dozen diaphragm pumps. All with good motors, but no longer make proper pressure. Mine all went bad pumping water that had been thru a 5 micron filter. One pumped 1 micron water.
Rarely debris will build on the valves or diaphragms, but mostly the rubber like items loose their stiffness. They no longer make pressure or bleed off pressure when resting. Also the pressure micro switch commonly fails. It wasn't designed for DC service and is found in microwave door switches. Many people replace the switch with a well pump switch.