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torbmi
06-01-2005, 05:23 PM
'89 Tristar 190. Ran great this past weekend, but unless I'm getting the best mileage of all time, my fuel gauge is pegged to full and won't budge. When I turn the ignition off, it goes to empty, but as soon as I turn the key it stays on full. I had the sending unit in the tank replaced at the end of last season, and the gauge worked fine during the first couple of outings this year.

Any thoughts? Thanks.

Hunterb
06-02-2005, 06:14 PM
I think you need to look at your wiring. Usually a pegged guage means a short between the power supply (pink wire I think) and the ground. Make sure everything is connected properly. If it is then I would look at the sending unit to see if something is stuck and not allowing the float to lower down out of the full position.

Just a couple thoughts. I just replaced my sending unit because my guage red empty all the time. New sending unit and I'm good to go.



Bruce

stevo137
06-04-2005, 11:02 PM
My fuel gauge is not working properly either.
It jumped around for awhile, now it just shows about an 1/8 of a tank even after I filled it with 15 gallons. :huh:

Laurel_Lake_Skier
06-04-2005, 11:20 PM
Both of these problems sound like the float in the sender is stuck in the tube or magnets have come loose. There are quite a few posts somewhere here on disassembling the sender, sanding the float/ regluing the magnets. Do a search for the topic. I did this diy fix last summer and it took care of the problem. I suppose at some point I'll be looking at getting a new sender but after the fix, everything seems be working as it should.

r69mastercraft
06-07-2005, 12:21 AM
I tried doing the Fix about glueing the Magnets on, but i only had 1 Magnet and my replacement Mag must not be strong enough. Has anyone tried the cheaper fuel sending untis ? Does anyone know these won't work ? The replacement for the Tube one is $100+ I can grab the cheaper replacements for $20 bucks !!

Leroy
06-07-2005, 01:47 AM
More fuel gauge problems? Boats and Jeremy's truck!

teddy
06-21-2005, 10:48 PM
My 90 Pro Star had a similar problem. I hadn't tightened the screws holding the guage into the tank enough and the guage stuck on the top of the tank. It would read out of the tank so I knew it wasn't the sending unit. It could be lots of things but this fix was quick cheap and effective.

Good Luck

Hunterb
06-21-2005, 11:25 PM
I replace mine with one of the $20.00 teleflex sending units. It seems to work fine. I just did it recently so I can't comment on the longevity.

Good luck

Bruce

lakes Rick
06-22-2005, 01:18 AM
I replaced mine with the expensive one and after I dialed it in correctly my gauge works great....

erkoehler
06-22-2005, 01:35 AM
Here is a weird problem for you:

When I turn on my navigational lights, my fuel gauge pegs itself all the way to full and my tach stays at the last RPM before turning on the lights!
Any other time, the fuel gauge functions normally w/ lights off.
Anybody have a solution for that one?

Leroy
06-22-2005, 02:06 AM
Leave the lights off.... Hard for me to imagine how this is happening, but...

Get a voltmeter and start tracing the 12 volts. Likely a weak connection, either ground or +12. With one connector problem already, you might just go in wiggle each connector you can find. Get someone to look while you do that so you can find the culprit if it shows up. You can also just switch on/off the lights and find out where the voltage changes.

Here is a weird problem for you:

When I turn on my navigational lights, my fuel gauge pegs itself all the way to full and my tach stays at the last RPM before turning on the lights!
Any other time, the fuel gauge functions normally w/ lights off.
Anybody have a solution for that one?

Hunterb
06-22-2005, 02:37 PM
Erkhoeler,

That's almost certainly a ground problem. Check the ground connections on your lights. I just had a similar problem with the ground on my blower. If I had the blower on the temp guage and the oil pressure guage would read high (not pegged but the temp would read over 200 when the motor felt barely warm). If I turned the blower off everything went to normal. I fixed it by installing a new ground for the blower. I also ran a separate ground from the main connection block (at the back of the motor on mine) directly to the main ground wire where it bolts to the block. An electrician friend of mine explained that current will search for a ground and will often end up running through other guages etc. to find it. That messes up the guages it runs through.

Hope that helps.

Bruce

erkoehler
06-22-2005, 03:06 PM
So, would I need to ground the switch, or the actual lights? The boat is in Northern WI right now, and I am in Chicago, so it will have to wait till the 4th.

Hunterb
06-29-2005, 04:19 PM
I'm not an electrical expert, but I would check the ground for the lights really carefully. If it is when you turn the lights on that the problem starts then I would start with that. You may be able to test it by simply hooking up a jumper wire from the light ground wire to a known good ground (like the battery negative post) to see if that fixes the problem. I would suggest not using a multimeter as they can produce confusing results. You may want to try running the jumper from several different locations.

Hope that helps.

Bruce