Poontoon boat tank sending unit

[jerkputter]

I have a 2005 Harris 24 foot Flotebote that I need a tank sending unit for. I ordered a Moeller universal 4 inch to 28 inch and I cannot get it to work. No matter which I way I turn it the baffles get in the way. The original sending unit had the resistance wire windings at the bottom of sending unit. It went straight down and then turned 90 degrees with float arm not being that long. The tank is 24 inches deep . If I set the Moeller to how the instructions tell me it will be 23.5 inches . I tried turning it 90 degrees and it still hits the baffles in tank. I included a picture of my original and the one I bought and original so anyone can see the problem I am having. I know there has to be one out there that will be similar to the original. Moeller never returned my call as I sort of figured. I am stuck with the new one but don't really care. I just need one that will work in this tank. Thanks for any tips and help. Tom

 

[Silvertip]

Is the float arm the same length as the original? If not, the float should be adjustable up and down the arm. Adjust the float to the same position as the old one and cut off the arm..

 

[Silvertip]

Having the resistance element at the top on the new sender merely means you need to cut the arm or even bend it such that the float is even with the bottom of the sender and can travel upward to the point where it is even with the bottom of the mounting flange. This is a simple float system. Length of the arm is no an issue so long as the float can travel full up and down. You are just making the arc shorter. By the way, when you tighten the nut that secures the sender wire, make sure that stud doesn't turn. Look carefully at how the resistor is connected to the stud and you will see why many senders are assumed to be bad. The short connecting tab can turn and short against the sender frame.

 

[jerkputter]

The original float arm is 12 inches. It sits at bottom of tank straight down from resistance element so therefore it only goes out 12 inches toward back of tank. No baffle to hit that way. The new universal sending unit is set to 23.5 inches and it goes in at an angle all the way to back of tank. Somewhere alone the line it hits the baffle and only will read 1/2 tank. I have moved it 90 degrees both way according to instructions and it will not work as it still hits something. I know it works because I pull it back out and move the arm up and down and the gauge works like its supposed to. The instructions tell me never to bend the arm and if I did it would never touch the bottom of tank. I am a little confused on what you are saying ?? If you look good at the picture I showed you will see what I am referring to. I understand this is a simple float system but the only way I see a universal unit is going to work is have one like the original, meaning it will have to go straight down in tank and then float arm extends out 12 inches or close to that. Of course I could bend it and it would never hit anything but it would also never touch the bottom of tank. I cut it just like the instructions told me to. Measure from bottom of tank which is 24 inches and then cut to where the overall it is 23.5 inches. But because it goes in tank at an angle I see no way it will work.

 

[jerkputter]

I would think I would need one like this to make it work correct but I might be wrong. Somewhere I am missing what you are telling me. I hope I explained what I am telling you ok. I do appreciate your help but I just wanted to be clear that I have tried many ways to make one like I bought work. I ever ordered another one and it was just like the first one. I do believe I have to get one like I showed in this picture in order for it to work correct

 

[gm280]

They do make many sizes of both a floater swing arm type and a reed valve type. So you have to get one that suits your tank depth pretty closely. If the swing arm is a problem, you can buy a reed valve type that goes straight down without any swing arm. But they are pretty expensive too... I would first try to buy one that is made closer to your tank depth and not so much a one size fits all type... JMHO!

 

[jerkputter]

Thanks JMHO. I don't think I need the reed valve type, just one close to the original one that came out. The one I bought just will not work, or at least I cannot get it to work correct and I have tried everything I know. I am not a marine mechanic but I have worked on cars and trucks for 54 years so I know how to rig things. This tank should be no difference than any tank. I have no clue where the baffles are located inside the tank. All I know is I can feel them when I try and install the Moeller I bought online. It is supposed to work on any tank up to 28 inches. I am not in good enough shape to lean over trying to make this one work for too long. If I could locate one that goes straight down with arm swinging at resistance element I know it would work as you can see in my original pictures of the old one. Better yet finding the original one would work even better and I included it in the picture. I have no clue what brand it is. Thanks for the help on this. Tom

 

[jerkputter]

OK, here is the lasts update on the tank unit. I went to the boat this morning and removed the tank unit. I then took an old coat hanger and used it to probe inside the tank. This unit is not going to work because there is not enough room for it to extend out at the top part of tank. The tank goes down at a 45 degree angle all the way around and the most I could probe the hanger is 12 inches without hitting the sides. This is 360 degrees so I would have to use a sending unit like the original one. I finally heard from Moeller and they tell me this one will not work even though it tells me it is universal. This is a 50 gal tank with a tag on it saying Harris Kayot. I put the one back in so it would be sealed up until I can get the right one and being it was not good to me I bent it some to make it at least read 1/2 tank when it is really 3/4. I could only get it even close to reading 1/2 tank by bending the unit arm at about the 4 That will have to work for now but regardless what people saying around universal sending units working it is not always true. There were no baffles as I could feel, just the way the tank was designed meaning the top half had never little room in it. These universal sending units with the resistance element at top will no way work in this tank. The top part of this tank is shaped like a funnel for some reason. Anyway I will order the correct one this winter when I take the boat out. For now being it is reading 1/2 tank when really its 3/4 full I have something to go on. I will just never let it get below the E on the dash unit. Tom

 

[Silvertip]

With an odd shaped tank as yours apparently is, then you are probably correct that this sender won't work. But what is confusing is why is this tank shaped so strangely for use on a pontoon. These tanks are usually just the very generic square or rectangular units. I see no reason for it be shaped so strangely unless it had to fit around obstructions. With an irregular shaped tank, a float type fuel gauge is really not very accurate. Think of a cone shaped paper cup. With a float system on that shape, 1/2 tank of fuel is nowhere near 1/2 the volume of fuel in the tank. Way more than 1/2 of that fuel is in the upper portion of the cone and very little of the fuel is toward the bottom half of the cone. Your tank is apparently not dramatic of an example but the principle still applies.

 

[jerkputter]

I am not sure why it was made this way myself but it is. The gas gauge has always worked in the past correct until it went bad. Just looking at the outside of this tank it looks different than a regular square or rectangular tank. I am sure the engineers had a reason to make it this way, I just wish I know the reason. I am still searching for the original tank unit but so far no luck. Just don't want to buy one and have the same problem I am having now. Open to suggestions though ? Thanks. Tom

 

[gm280]

After rereading and looking closely at the pictures of you original sender unit, you need one that the swing arm is located on the bottom and not the top. And I have seen such replacement types. So look for one that can be adjusted anyplace from top to bottom and that one will work out. Just make the swing arm the exact same length as the original one and install it.

 

[jerkputter]

Thanks gm280. That what I had decided but got to find one that is ok in price and will work being I have wasted money for the one I bought.

First time for everything.

I thought this would be a simple repair but not so. For what reason they made a tank like this is a mystery to me?
Maybe this will help someone else that is planning on installing a tank unit with resistance element at top . Look close at the inside of your tank and inside if possible.
I am sure there was a reason the tank was made the way it is
them.
I like the idea of a large tank which keeps me riding longer. Tom