Heat exchange raw water pump, pressure unit

[Saltydoc]

Presently having the heat exchange unit on our Marine Trader Europa (In Australia known as Blue Seas 36) overhauled. Boat built in 1981 in Tiawan. Powered by a single Ford Lees 120 hp.
Now fitted with a raw water pressure unit gauge that detects if the raw water pump is not operating. Unit has seen much better days and gives no indication of make. Pressure unit connects to warning light on dash.
Now need to replace the pressure unit fitted to the hose.
Would anyone know where such a unit would be available or even what pressure would dis-alarm the dash light, as several pressure units are available in auto shops.
I imagine our present unit was retro fitted as it does not appear in the Ford Lees manual.
Dennis

 

[psneeld]

Pictures might help.

Aqualarm uses a sensor that isn't pressure but flow and has a red light and horn at the dash. Their sensor is a gray pvc tee that is placed somewhere in the raw water circuit.

Any low pressure contact switch suitable for use in saltwater may work....depends on what you really want it setup like.

 

[Saltydoc]

Thanks Psneeld for your expert guru advice. Exactly what we were chasing.
Bit of web search and a phone call or two and we were able to locate the Aqualarm distributor in Australia.
Ordered the Aqualarm 10333 which should arrive in an 'express post' bag in the next day or so.
Hopefully we are now advised early of any raw water pump mal-functions.
Nothing like peace of mind while cruising in the Great Sandy Straight and Hervey Bay.
The Humpback Whales are just starting to arrive in Hervey Bay on their annual pilgrimage back from the Great Barrier Reef. Hervey Bay is known as ' the whale watch capital of the world'.