80's Bayliner fuel gauge/sender ohm range?

[62Scout]

'85 Bayliner bass boat..fuel gauge reads half when the tank is full...I get that fuel gauges are just simple ohm meters that say fuel on them instead, but what I don't know is what ohm range they're supposed to be?

Are these things pretty standard in the marine world, or are they like cars where different OEMs have their own different full/empty ohm readings and flange fittings?

I figure it's _probably_ just a bad sender, but I've never been one to just "throw parts at the problem" before doing diagnostics.

 

[QBhoy]

There are two variations. Eu range and us range. Each are almost the opposite scale from each other. But if it’s reading halfway when full..it’s more likely I’d be thinking about the condition of the wiring and its continuity ability or its terminals. Or perhaps also likely that the actual mechanics of the sender suffer corrosion to the actuator arm…or the float itself has become a little porous

 

[62Scout]

Yes, could be a number of reasons...which is exactly why I prefer the "diagnose, then replace" method. But if I don't know what ohms the sender & gauge are supposed to be seeing, I'm still taking a wild guess on that part.

I would assume that it's set up for US market, as I'm in the USA.

 

[QBhoy]

Yes, could be a number of reasons...which is exactly why I prefer the "diagnose, then replace" method. But if I don't know what ohms the sender & gauge are supposed to be seeing, I'm still taking a wild guess on that part.

I would assume that it's set up for US market, as I'm in the USA.

Can’t remember just precisely. But the US spec is something like 230ish ohms empty and all the way down to 30 or 40 ohms full. EU is about 0-190/200 ohms empty to full. Double check the exact figures if you need to..but it’s about that anyway, I’m sure. Check the continuity between the wire ends (disconnected) at the sender end, to gauge end too perhaps. Check the other wires for compromises at the gauge too. But ideally just take the sender unit right out the tank and test it, as you likely plan to anyway. Keeping the associated wiring still connected of course. If it’s had this issue since you’ve known the boat and perhaps an unknown…it could even be that the sender unit ladder or adjustable range setting is wrong.

 

[04fxdwgi25]

 

[Scott Danforth]

clean the connections at the sender and the gauge

 

[brodmann]

When I had problems with my gas gauge, I went to test the sender and it had the ohms range stamped on the flange.