02 340AJ fuel tank specs

[LadyLauraIV]

Would anyone happen to know the measurements on the 340 aj fuel tanks?
more specifically the depth, i would go to my boat to measure but im very far away at this time and wont be back for a couple of months. wife wants tube style sending units(me too),
and wants to get them and other things together so i wont be bored when i return.

 

[Jimmy Buoy]

Tank depth is 19.5" but how do I know that? Years ago I ordered SSI Technologies Ultrasonic tank level sensors that are very accurate and need to be ordered to a specific depth - I ordered a pair of 18" ones so when the sensor knew the fuel was 18" below it read "zero" on my analogue fuel gauge but I'd still have 1.5" of fuel remaining as a buffer. Sadly, one of the sensors crapped out after 7-8yrs and when I went to order another they no longer stocked the 18" but would do a run of 10 or 20 if I'd like. Nope. Too bad...

 

[LadyLauraIV]

Tank depth is 19.5" but how do I know that? Years ago I ordered SSI Technologies Ultrasonic tank level sensors that are very accurate and need to be ordered to a specific depth - I ordered a pair of 18" ones so when the sensor knew the fuel was 18" below it read "zero" on my analogue fuel gauge but I'd still have 1.5" of fuel remaining as a buffer. Sadly, one of the sensors crapped out after 7-8yrs and when I went to order another they no longer stocked the 18" but would do a run of 10 or 20 if I'd like. Nope. Too bad...

What did you end up replacing it with?

 

[Jimmy Buoy]

When it failed I still had the old manual "arm" tank sender so reinstalled it for a while. It was so inaccurate compared to the ultrasonic (not registering any fuel use for the first part of the full tank being used, the tank readings would drop much faster for the lower half of the tank, and it would register almost empty when a fill-up proved the tank still had between 1/4 and 1/8 tank of fuel remaining.
I called the company and found things had changed since first ordering. I'd actually need to buy 30 to get the right size but they did have a 17" gas sensor in stock so I bought that. I just know that while it indicates full down to 1/8 tank, it is actually reading from full to 1/4 tank. There is also that buffer of fuel below that so about 3/16 tank remains even when reading empty. Not the best solution, but usable.