Internal water tank sensor?

[Bongi]

Has anyone added a fresh water tank level sensor to the metal tank in a 1980’s era GB42C?

I am fitting a ribbon-type SCAD holding tank sensor and have in mind to add a fresh water tank sensor as well.

I bought a vertical rod-type sensor for the fresh water tank, but am now wondering if there will be a way to thread it past the baffles in one of these tanks to meet the sensor requirements to be a few inches away from internal tank components or walls.

 

[Bongi]

Clarification: the ribbon sensor is for the fiberglass holding tank.

The question is about the “rod with float” sensor for the metal fresh water tank.

 

[Mike GB32]

I'm in the process of installing what sounds like same system on my GB32.
I've already installed a Scad TM2 monitor and use it for my black water tank.
For the fresh water, I drilled the tank and added a Uniseal 1 1/2" rubber adapter and a 1 1/2" PVC female pipe adapter (per Headmistress Peggy's advice) and plan on adding a KUS S5U sender.
https://kus-usa.com/product/s5u-sender/
Just waiting on the factory to start accepting orders in September.

 

[Bongi]

Hey Mike, that’s exactly the sensor I got for the fresh water tank. Possibly the baffles on the GB32 tank are such that you can more easily locate the sensor so it is free of interference.

The GB42 tank on ours seems “more baffled” such that I can barely get the stick measuring rod down the filler pipe without hitting one.

I guess I need a blueprint of how the baffles are arranged in the fresh water tanks of 1986 GB42 models (#968) to get a workable place to mount the sensor.

 

[Mike GB32]

Yeah, on my old (1974) tank I have a small square inspection port on the side that I opened up to find the baffle locations. I was able to create an access panel in the bottom of the starboard settee to drill the top of the tank. Sorry I can't be of any real help.

 

[firstbase]

Hey Mike, that’s exactly the sensor I got for the fresh water tank. Possibly the baffles on the GB32 tank are such that you can more easily locate the sensor so it is free of interference.

The GB42 tank on ours seems “more baffled” such that I can barely get the stick measuring rod down the filler pipe without hitting one.

I guess I need a blueprint of how the baffles are arranged in the fresh water tanks of 1986 GB42 models (#968) to get a workable place to mount the sensor.

Would like those blueprints as well for my 1987 42Cl, #996.

 

[Bongi]

Completely fortuitously, while at the Seattle Boats Afloat show, I had an opportunity to talk to Tony Fleming about this issue. He noted that all the modern boats use external water sensors to measure water level in a tank.

This of course simplifies the issue since you just add that at the bottom of the tank and don’t have to stress threading a rod sensor through an array of baffles.

I’ve done a little poking around and it seems there are few types… pressure and ultrasonic types. The sensors can output voltage or current fluctuations as level measurements.

Here is an example from Safiery for their senders of various favors which use this mounting arrangement - in this case when paired with a Victron GX140. They can be paired with the SCAD monitor display unit too.

https://university.safiery.com/view/733081500/