Fuel Sending Unit Repair

[Skipper]

Originally Posted by jude09

Did you have to remoce the tank

You must at least disconnect the straps and pull it out to clear the sending unit. Really not that big of a job. Have to first remove the combing pads in the back corners. Then the carpeted back filler board. There are just clamps that lock onto the tank. Unscrew the clamps and the only thing left holding the tank in place is the filler hose.

[monsoon]

Just did this repair on my '98 Prostar 190 a couple weeks ago after reading this thread. After disassembling the unit, I found only a single loose magnet inside the cylinder. I figured I had dropped the other one when taking it apart. Looked around nervously on the floor for a while, then inspected the float and saw only one end of the slot showed signs of old glue where only the single magnet would have been mounted. I carefully sanded the outside radius of the float to reduce its size and allow it to move freely up and down inside the cylinder, remounted the magnet with super glue, reassembled the unit, and it's been working fine for two weeks now.

[jeverett]

It was a heck of a lot easier just to buy a new one from Skidim.

[ricford]

But a heck of a lot cheaper and satisfying to do it yourself. Just completed this fix using this thread two weeks ago on my 96 prostar. Worked like a charm, and I borrowed the super glue so it didn't cost me a cent. Thanks very much!!!

[monsoon]

"Easier to buy a new one"... Maybe... I'm not knocking Skidim here, I love the place and how helpful they are, but they haven't built a very good database on what model sending unit fits what year and make MasterCraft yet. After asking me if i had a 2 or 3 wire unit, and after having to get back to them the following week (boat and lake house is an hour away from where I live) they then asked me how deep my tank was. Seems there are 3 or 4 different length units to choose from. I told them I'd have to get back to them again the following week. I took a tube of super glue with me and while i had the unit out to see how long it was, I opened it up and did the repair.

If you're going to by a new unit, you'll need to know these two things.

[725mastercraft]

I have a 1993 PS190 and my fuel level sender did not look exactly like the one in the OP picture. In fact, the bottom of the unit was sealed with no way to disassemble it without tearing it apart. So, I ended up buying an brand new MasterCraft fuel level sending unit for 70$. The new one looks more sophisticated in the fact that it is a much narrower aluminum tube. Apparently there is no float inside the new one. Worked very well. Price for a brand new Mastercraft fuel sending unit, 70 bucks. Price for a brand new prostar190, 60 some K. Fixing a 20 year old boat myself, priceless!

[mbeach]

magnets must repel each other and are placed at ends of float. easy fix as long as the polarity of the magnets is oriented correctly.

[FrankSchwab]

After seven years, mine broke again. Rather than take it apart and fix it again, I ordered a unit from Wema that seems nicer. Everything is protected inside the stainless steel tube, except the float (and presumably magnets), which have a bit more clearance on the shaft than the float on the last one did inside so should be less likely to hang up.

Worked fine so far on the one trip we've done.