Fuel Sending Unit Repair

[Worthing skier]

Hi all

My Fuel gauge reading was playing around a bit last seat season , normally reading low.
With the track record of the sender units I have today taken it out with a view to find a magnet related fault , however the sender unit I have is a plastic tube and it does appear to have any retainer screws to enable me to get in side it .
By tipping up and down I can see the float move around but it does get stuck , which I am sure the the route cause of the problem .
There is a plastic plate on the bottom of the unit , which I would thin could be prised off and re glued .
Has any one come across the type of sender unit and if so how did you get inside.

thanks


Kevin

1993 prostar 190 285 hp inamr.

[Worthing skier]

Update ,

Pried off the lower plate , sender setup up and design same as pictures, found both magnets stuck together in the middle of the float, cleaned the tube , glued the magnets back in their correct site (poles apart) , sanded down all the faces of the float , rebuilt it . glued back on the base cover.
Tested in and out of tank , now gauge works good as new .
Cost me £3 for the glue and a couple of hrs but saved me £150.00 for the part and I now know exactly how it works and it is done correctly (priceless).

Many thanks to all for this thread.


Kevin

[mrprostar]

Plus one more for this being the problem. Solved now. Thanks.

Just one question. My magnets were stuck together when they fell out. They are supposed to go into the slots on the top and bottom of the float and not in the middle? They need to be put in so they repel each other? I put them in the middle and the gauge was working, so I didn't think much of it until I came back and looked at the pictures again.

[NatesGr8]

I did this same repair on my 94 Prostar about 3 years ago...worked like charm. Excellent write up!

[Barefooter92]

Going to work on my fuel sender this weekend and dug this thread out.

What epoxy shall I use for the magnets submerged in fuel?

[Worthing skier]

I just used super glue

[captkidd]

Originally Posted by Worthing skier

Hi all

My Fuel gauge reading was playing around a bit last seat season , normally reading low.
With the track record of the sender units I have today taken it out with a view to find a magnet related fault , however the sender unit I have is a plastic tube and it does appear to have any retainer screws to enable me to get in side it .
By tipping up and down I can see the float move around but it does get stuck , which I am sure the the route cause of the problem .
There is a plastic plate on the bottom of the unit , which I would thin could be prised off and re glued .
Has any one come across the type of sender unit and if so how did you get inside.

thanks


Kevin

1993 prostar 190 285 hp inamr.

My '94 PS205 also has the plastic sending unit tube. After reading this thread I pulled the sending unit out and sure enough, the magnets were stuck to the back of the circuit board (I had to use a razor knife to cut the bottom plate off the tube). It looked like the magnets had been closer together, possibly one on the end and the other near the middle (based on where it looked like they had been glued), so this is how I reglued them. Now a few questions:

- Should the magnets be at opposite ends of the float, with the poles repelling each other?

- Are the magnets supposed to touch the circuit board as the float slides up and down? Mine appear to be about an 1/8" from the circuit board.

- If I reassemble the unit and reconnect the wires, will the fuel gauge register full if I turn the sender upside down and let the float go to the top, or does the unit have to be submerged in fuel in order to work?

Thanks.

-

[wgtruemper]

Awesome write up, I pulled my sender this weekend and found 1 magnet completely dislodged. Works great now, hopefully it stays that way.

[formosa]

Great write up - thank you. I would only add that I only had one magnet on my float. I confirmed this by only finding one magnet when disassembling, as well as there was only one visible area on the float that anything was attached to. Not having another magnet handy, I tested successfully with one magnet (both ohm meter and fuel gauge). I do not want to confuse anyone off your instructions, just relaying my situation.

Also, how did you manage to get the round/slotted nuts off to remove the circuit board? I ended up using vice grips to loosen although based on the amount of work I put into it --- I'm certain there must be the right/better tool given the slots on each side of the bolt.

Thanks again - this is an awesome write-up!

[jude09]

Did you have to remoce the tank