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Chicago190
07-07-2009, 04:50 PM
I took my fuel sender out because my gauge was stuck at the 3/4 mark. Everything moves freely so I want to test it out of the water. 2 things:

1. Where does the little square magnet go? Mine came out when I removed the bottom piece and I want to make sure I put it back in correctly. This is the Isspro sender out of a 1996.

2. Silly question, but can I use a bucket of water to test its function, or does it need to be submerged in fuel?

flipper
07-07-2009, 05:16 PM
There should be a hole in the foam that the magnet came out of IIRC. As far as testing it, just turn it up side down and back to see if it moves the gauge. I'd use a gas can if possible before water. To check the gauge, touch the two wires from the sender together and it should read full.

Chicago190
07-07-2009, 05:26 PM
Thanks, can you confirm the picture is correct?

Also, do the magnet just stick in, or should I use something to hold them in place? I have epoxy, but I don't know if it's safe to use in gasoline. Do I have to worry about what direction the magnets go in? At the moment I am unable to remove the circuit board because the 3 screws holding the top on are a hex size I am missing from my tool box.

flipper
07-07-2009, 05:32 PM
It's been a while, but I think I had to pull the board out to get the foam out, then you'll see where it goes. Not sure about the epoxy, but you have to make sure it's okay for fuel if you do use one. i just stuck the magnet in on mine and it was fine.

JimN
07-07-2009, 05:34 PM
Try Super Glue. That shouldn't be affected by the gas.

Chicago190
07-07-2009, 05:51 PM
Can I pull the board out from the bottom or do I have to remove the 3 screws securing the black plastic top to the metal tube to remove the board and top as 1 piece? I'm worried there are connections at the top of the board that will be damaged if I pull the board out from the bottom.

Thanks again for the assistance.

flipper
07-07-2009, 06:01 PM
Yeah, you need to take out the screws on the top to get it apart. Worst case, Skidim:D

Chicago190
07-07-2009, 06:23 PM
It seemed to work alright when I just dropped the magnet down the tube so hopefully it means I can salvage this one.

mayo93prostar
07-08-2009, 07:10 AM
I sanded my float and superglued the magnet back in mine last year and it worked for a few months but then started sticking again. I bought a new metal tube type unit from skidim and it works much better other than a slight wiring problem. I recommend buying a new one so you do not have to mess with it again.

Chicago190
07-08-2009, 09:48 AM
Thanks for the advice. I've determined my issue wasn't the float sticking, but rather the magnet had come out of the float. It was stuck to the 3/4 mark on the circuit, but the float was still moving freely. I'm going to reassemble it this morning and hope it works again. I've attached a picture of the fuel sending unit disassembled for future reference.

Chicago190
07-08-2009, 12:16 PM
Gauge and sending unit are functioning again.

By the way, getting at the top my of the fuel tank on my generation Prostar 190 is a huge PITA, especially the rear seat bolsters. I had to use a double nut on two studs to remove them, which is not easy given how little room there is around the fuel tank. The port side rear seat bolster had me swearing pretty good. I got a good idea of how well the boats are put together because they do not come apart easily.

hajovrd
09-10-2009, 10:20 PM
Just wondering what you ended up doing to fix your sending unit, I have the exact same problem.

mbeach
11-27-2009, 08:45 PM
i have 2 magnets on my float. do they both go together the grove in the center of the float or one at each end of the float?? not going to reassemble until i know for sure.

mbeach
12-10-2009, 09:34 AM
fixed and working fine now. just be sure the magnets are reassembled one on each end of the float groove with poles repelling each other.

Chicago190
12-10-2009, 12:36 PM
My repair worked for awhile, but it started acting up after awhile. I think the problem was I used old glue that wasn't really fit for the purpose. Haven't decided if I'm going to try to repair it again or just go with the new fuel sending unit from skidim.

Also, I don't know if it matters which way the magnets are inside the float. I put mine with the poles attracting each other and it worked fine.

CantRepeat
12-10-2009, 01:29 PM
I got the metal one from skidim as well. I used a tubing cutter for the outter tube and a die grinder with a cut off wheel for the smaller inner tube. The adjustments are pretty easy if you have an empty tank and a friend.

Empty tank, screw the empty screw until friend says the gauge reads empty. Go fill up the tank and turn the full screw until friend says gauge reads full.

captain planet
12-10-2009, 01:56 PM
I got the metal one from skidim as well. I used a tubing cutter for the outter tube and a die grinder with a cut off wheel for the smaller inner tube. The adjustments are pretty easy if you have an empty tank and a friend.

Empty tank, screw the empty screw until friend says the gauge reads empty. Go fill up the tank and turn the full screw until friend says gauge reads full.

I would recommend going with the new unit. My 98 had the one with the float as well and it failed. For what it takes to get yours out to work on, the new style has worked without fail for 8 years now. But that is your call.

Chicago190
12-10-2009, 02:08 PM
I would recommend going with the new unit. My 98 had the one with the float as well and it failed. For what it takes to get yours out to work on, the new style has worked without fail for 8 years now. But that is your call.

I agree, getting the sender out on the 190 is a bit of an ordeal. I may make one more attempt with the current one using better glue, since my float physically moves fine and the sender still reads accurately, just that the magnet won't stay in place. Plus, I have to uninstall the rear pad this spring because the stitching has torn through the vinyl and I need to have it repaired. At that point I'll have half the rear interior out so it won't be THAT much more work.

Sodar
12-10-2009, 02:11 PM
Use foam safe epoxy on the magnet. It worked on my '96 for a few seasons before I sold it.

If you decide to replace... http://www.isspro.com/products.php?cat=99

uncleboo
12-10-2009, 04:08 PM
I just replaced this style float with a new one from ski dim. I had taken the old one apart multiple times only to have it stick after a few weeks. Got fed up and decided to fix the problem once and for all. For the new unit, I had to cut down the outer tube with a tube cutter and then snip the inner tube. It took about 2 minutes to do. Plugged it in, touched the little magnet to the top, and I was all set.

Jesus_Freak
12-11-2009, 12:50 PM
I just replaced this style float with a new one from ski dim. I had taken the old one apart multiple times only to have it stick after a few weeks. Got fed up and decided to fix the problem once and for all. For the new unit, I had to cut down the outer tube with a tube cutter and then snip the inner tube. It took about 2 minutes to do. Plugged it in, touched the little magnet to the top, and I was all set.

What kind did you get?

I got this one and still dont like it...http://www.skidim.com/prodinfo.asp?number=CENT395063.

Jesus_Freak
12-11-2009, 12:52 PM
2. Silly question, but can I use a bucket of water to test its function, or does it need to be submerged in fuel?

The density of water is about 40% higher than that of gasoline at room temperature, but both densities are far higher than that of the float. As long as the latter is true, you are good to go.

Chicago190
12-11-2009, 03:30 PM
So does anyone know definitively if the magnets are supposed to have the poles opposite, or does it not matter? I'm wondering if my problem is that the magnets are not installed properly and they are causing strange readings? Right now my gauge will read the correct level, then drop to totally empty, then it will jump back up to the proper level.

Muttley
12-11-2009, 03:45 PM
So does anyone know definitively if the magnets are supposed to have the poles opposite, or does it not matter? I'm wondering if my problem is that the magnets are not installed properly and they are causing strange readings? Right now my gauge will read the correct level, then drop to totally empty, then it will jump back up to the proper level.


I did the fix on mine (even did a write up with pics) and that's the problem I have. One minute it's reading full, the next it drops to empty. I put the magnets in together because I didn't know. I haven't had the chance, but I'll eventually pull it and set the magnets as mbeach described.

Chicago190
12-11-2009, 03:51 PM
I did the fix on mine (even did a write up with pics) and that's the problem I have. One minute it's reading full, the next it drops to empty. I put the magnets in together because I didn't know. I haven't had the chance, but I'll eventually pull it and set the magnets as mbeach described.

Interesting. mbeach, let us know if your sender works consistently.

Muttley, if you make the change before next April let me know how it works out for you.

In its current state, I'm not really bothered by the fact that the reading sometimes goes to empty, but if its an easy fix I'll make the change.

mbeach
12-11-2009, 08:01 PM
did fix as recommended by jimN and has lasted 6 weeks with no problems. way i determined correct orientation of magnets was to align with attracting poles at first which produced results described by another poster - gauge drops to empty as float is slid up and down the sending unit circuit board. when i reversed polarity so magnets repel each other, gauge advances smoothly as float is slid up and down circuit board. be sure to smooth the float surfaces (also suggested by jimN) honoring both the curved and flat surfaces using something as a file or in my case sandpaper. lastly, as recommended by jimN, i used superglue to reglue the magnets to the float. hope this helps.

Andyg
12-11-2009, 08:44 PM
I did the same repair on my old 97 190. Instead of using super glue I used JB weld. I repaired it in 2000 and I know it is still working today as my friend now owns the boat.

andyg

Chicago190
12-12-2009, 12:16 PM
Do you force the magnets close to each other in the middle of the float, or do you put one magnet at the top and one at the bottom of the float (if this makes sense)?

mbeach
12-12-2009, 12:58 PM
Do you force the magnets close to each other in the middle of the float, or do you put one magnet at the top and one at the bottom of the float (if this makes sense)?

the float is grooved on one side and rounded on the other. put the magnets on each end of the float in the groove with repelling poles and slide the float up and down the circuit board with power to the board and key on. watch the fuel gauge as you slide the float. you can tape the magnets to the float to test rather than glue them and find they are installed backwards.

uncleboo
12-15-2009, 01:40 AM
Jesus Freak, that is the one I got. It looked much different than the one installed on my 190. I thought they has sent me the wrong unit, but after a conversation with the folks at ski dim I found out it was correct. The previous model with the float is very prone to failure. They said MC switched several fuel sending units over the years until settling on this one. The design is intended as an improvement over the previous models and the inferior float design. I toiled with the float on my sending unit for about a year before I finally bit the bullet. I have been pleased with my new unit thusfar. My old one stopped at 3/4 of a tank, this one reads both full and empty. No more having to guess how much gas is actually in the tank or taking the old unit apart every couple of weeks when it quits working.

JimN
12-15-2009, 10:27 AM
Jesus Freak, that is the one I got. It looked much different than the one installed on my 190. I thought they has sent me the wrong unit, but after a conversation with the folks at ski dim I found out it was correct. The previous model with the float is very prone to failure. They said MC switched several fuel sending units over the years until settling on this one. The design is intended as an improvement over the previous models and the inferior float design. I toiled with the float on my sending unit for about a year before I finally bit the bullet. I have been pleased with my new unit thusfar. My old one stopped at 3/4 of a tank, this one reads both full and empty. No more having to guess how much gas is actually in the tank or taking the old unit apart every couple of weeks when it quits working.

They only switched once in recent years (1999-current)- to the new style with no moving parts. They had several sizes available but for keeping inventory under control and not having the wrong part in stock, it's best to only stock the longest one and cut to length. The first ones that MC used had a three wire sender with an adapter to two wires but that only lasted one year and was a direct replacement for the one with the float which only failed once the ethanol became prevalent in gas. Before that happened, they were trouble-free.

CantRepeat
02-05-2010, 11:18 AM
What kind did you get?

I got this one and still dont like it...http://www.skidim.com/prodinfo.asp?number=CENT395063.

That is the exact one I put in my boat after the factory one stopped working. It has work fine for the last few seasons.

What do you know like about it?

Andyg
02-05-2010, 02:13 PM
Do you force the magnets close to each other in the middle of the float, or do you put one magnet at the top and one at the bottom of the float (if this makes sense)?


I never checked the polarity and just JB welded each magnet into the groove as far a part as possible. Like I said it has been about 10 yrs since I fixed it and I know it still works.

TEAL98
02-14-2010, 08:48 PM
This thread should be made into a sticky, I'm having similar gauge problems with my '98 as well. Getting ready to tear into it in the next 2 weekends. I keep putting it off, but it's damn cold inside that friggin' garage:mad:

ski/hunt
02-23-2010, 10:40 AM
What kind did you get?

I got this one and still dont like it...http://www.skidim.com/prodinfo.asp?number=CENT395063.

What don't you like about it? I'm replacing or might try the fix on ps205, and only want to do job once.

tomwilli2025
02-25-2010, 01:18 PM
I’ve got a 1996 190 Prostar and need to replace the sending unit. How many hour job is this and the difficultly on a scale of one to ten? Any pointers would be greatly appreciated!

mbeach
02-25-2010, 01:21 PM
Iíve got a 1996 190 Prostar and need to replace the sending unit. How many hour job is this and the difficultly on a scale of one to ten? Any pointers would be greatly appreciated!
i repaired mine and is working like a champ. i have a 98 sportstar so i assume we have the same sending unit. look at posts in this thread and search sending unit for some good posts with pics. getting tank in proper position so unit can be removed is most difficult part.

mayo93prostar
02-25-2010, 01:29 PM
I replaced the sending unit in my 93 prostar while doing some other work. You should be able to do it in under 2 hours. I had to remove the back seat and the rear panel, remove the gas tank hold down brackets, slide it forward, replace sending unit and reverse the process. not very difficult. Some newer models such as 96 may be a little more difficult to access the tank.

MariStar-Man
05-25-2010, 10:01 AM
Great thread. I'm going to attempt to repair the Sending Unit on my 1999 Maristar, using JB weld today. I'm assuming that the magnet fell out or off.

Was any of your magnets found at the bottom of the tank or just stcuk on the unit somewhere?

jimmer2880
06-08-2010, 05:17 PM
When I replaced mine, in my '95 PS190 last year, I ended up removing the rear tow eye, then made up a wooden block, which matched the 4 holes that the tow eye bolted to. I then drilled a 1/4" hole through the exact center of that hole. I then, used a hole saw, exactly 1/4" larger (1/8" on each side) than the existing hole, to slightly enlarge the hole through the fiberglass. That allowed me to remove and replace the sending unit from the tow eye hole.

All of that was much easier than pulling the tank.

Now, for the bad news. I had a 2-wire plug, with a separate ground wire. The unit I got from skidim, had the plug reversed. Couldn't figure out why it didn't work at first, but then saw that the manufacturer muffed it up. The manufacturer was useless. Skidim said they hate to use them, but they are the only option.

Now, for what makes me mad. I used to fill my tank with the ignition key on. That way, I could watch the gas guage and stop before gas started coming out my vent pipe. If you do that with this model, it will re-set itself to "full", regardless of how much gas is actually in the tank. Ohh well - better than running out of gas on the river.

Table Rocker
03-05-2012, 01:05 PM
This is a great thread on a repair I just completed. I put the magnets in the foam block in the outer sections of the foam and glued them in with Permatex Threadlocker Blue since I knew it resisted gas very well and I had it on hand. I installed them where they were pushing away from each other as instructed in the thread and I just tested it. It worked great!

I tested without the aluminum tube installed because I wondered if there could be an upside down for the float based on the polarity of the magnets. There was not. I slid the float up and down the circuit board and watched the gas gauge go up and down 1/8 at a time.

Many thanks to all on this board for saving me close to $100 by the time I paid to get a new sending unit to my door.