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DooSPX
11-05-2006, 08:37 PM
my battery reads 12.83 volts on a multimeter, but the volt meter reads 10 volts... do I need a new gauge? or can i fix it? AND, I think my fuel gauge is reading the wrong amount, because when i was testing the battery, I noticed my fuel level was "JUST" below half tank, but my gauge was reading an 1/8th of a tank. Can I test the gauge or the sender? and how do I do it?

thanks guys...

DooSPX
11-06-2006, 10:21 AM
anyone?
please...

dmayer84
11-06-2006, 10:26 AM
my battery reads 12.83 volts on a multimeter, but the volt meter reads 10 volts... do I need a new gauge? or can i fix it? AND, I think my fuel gauge is reading the wrong amount, because when i was testing the battery, I noticed my fuel level was "JUST" below half tank, but my gauge was reading an 1/8th of a tank. Can I test the gauge or the sender? and how do I do it?

thanks guys...

I was told by the dealer that there is an adjustment on the top of the sender to adjust the settings for the tank. One is for full and one is for empty, but I dont know which is which. Mine reads just under 1/2 a tank when it is empty, but I have to have it empty to adjust it, and then fill it up and adjust the other screw, going to have to wait till the spring. Guessing that you should probably need to do the same thing.

Footin
11-06-2006, 10:37 AM
I have the same problem with my volt gauge. The battery reads above 13 volts on a multi meter when running but the gauge reads below 12.

There is a purple wire on the key switch (ignition), I replace the connection and cleaned the area it connects to, and this fixed the problem for a couple weeks but now it reads low again.

I guess I will just have to live with it.

BIGBADBLUE
11-06-2006, 10:48 AM
I have the same issue with my volt gauge. Just use it as a relative gauge ... if it changes and goes down from where it normally runs then you have an issue and need to investigate.

I am no expert but this is what my dealer told me and the "smart" guys in here have said.

JimN
11-06-2006, 11:15 AM
Doo-

Before any adjustments are made to the fuel sender, make sure there isn't any actual grounding or corrosion issue with anything between the battery and dash wiring. Low voltage reading and fuel sender can be related. If the boat is from '99 or after, there is usually a way to make an adjustment but unless you know exactly how to do it properly, don't do it.

If the voltage issue has a physical cause like a loose connection, break in the wire that can flex and provide better/worse connection or broken terminal, the guage will not read the same at all times and there's a very good chance of being stranded because of an erroneously high reading.

The battery terminals, safety switch wiring, ignition switch or boat harness could be the cause. I would start at the battery posts and make sure they're clean & tight. Next, I would check the boat harness (tight and clean). Block grounds are next, then up to the ignition switch (tight and clean). Grounding buss is next and then check the terminals on the guages (tight and clean).

JimN
11-06-2006, 11:18 AM
Footin- are you measuring the voltage at the guage terminals or at the battery? If you're not taking this reading at the guage, it's not a valid test. If you check it at the guage, leave the guage connected.

I have seen some guages bind and in that case, it would need to be replaced.

rspiecha
11-06-2006, 11:51 AM
My 94 Prostar 205 volt guage reads low. Boat came back from dealer with a passing grade on the charging system. So keep an eye on it where it is now, and make that the normal reading.

Rob

JimN
11-06-2006, 12:28 PM
A low guage reading has nothing to do with the charging system if the voltage is correct at the battery. In this case, the low reading is a clear sign that there's a problem in one of the areas I mentioned before. If everything is OK, you won't have a normal reading one place and an abnormal one someplace else.

If the dealer checked the charging system and stopped there, they apparently have no desire to fix the problems their customers come to them with. If there's a low reading at the guage, either there's a problem somewhere before or the guage is faulty. What other guages are acting up?

DooSPX
11-06-2006, 03:16 PM
JimN the boat is a 91.
where is the harness you are speaking of?

helton333
11-06-2006, 03:36 PM
I have and 89 with the same issue. I use a MC certified who knows
more about MC than most MC in house as I live right outside the plant in Tennessee and he use to be an in house techinical mech.

he said it is the gauge and that over time, these for whatever reason bind enough to cause the problem.

He has checked mine every spring and found it consistently, 2 volts low.

JimN
11-06-2006, 03:41 PM
It is possible for the guage to be the cause, as I mentioned and was repeated. If you have access to another of the same kind, I would swap it to see if the problem goes away. That's the main reason I said to check the voltage at the guage. If your DMM shows the same voltage, you need to check further, if it's different, the guage is suspect.

The boat harness is at the driver's side rear of the motor and has 6 - 7 wires in it. Check this only if there's a major discrepancy between the voltage at the battery and at the guage.

DooSPX
11-06-2006, 03:45 PM
got it thanks Jim.
how do I check the fuel guage and/or sender agian?

thanks

DooSPX
11-08-2006, 07:24 PM
well, battery post are perfect, battery connectors are perfect, and tight fit on the cables.
I guess next is to look at the harness...

JimN, any idea's what to look for there?

JimN
11-08-2006, 07:45 PM
"The battery terminals, safety switch wiring, ignition switch or boat harness could be the cause. I would start at the battery posts and make sure they're clean & tight. Next, I would check the boat harness (tight and clean). Block grounds are next, then up to the ignition switch (tight and clean). Grounding buss is next and then check the terminals on the guages (tight and clean)."

I posted this before.

DooSPX
11-08-2006, 07:48 PM
ah, gotcha...
Thank you SOO much Jim

george111
11-08-2006, 09:58 PM
Hi JIm,

I thank you also for I have all the same problems on my 1994 2005 prostar. The advice is well received and appreciated.

Thanks,
George

wesgardner
11-09-2006, 01:57 PM
Just as an aside - wiring may LOOK good but may not BE good (particularly the crimp connectors) - I ended up pulling in a new wire from the battery up to the ignition switch and then back to the solenoid (thru the neutral safety switch) before my starting gremlins were gone...I also used 10 gauge wire...my boat STARTS.... (no more eating up solenoids, etc...I kinda use my panel gauge as a reference...nothing more, a good digital VOM is the ticket for checking voltages)...go 'round the boat with it one time, you might find some "stuff"...

Wes

tomparker
05-10-2009, 11:49 AM
My 87 prostar started reading low voltage at the gauge. Usually about 10.5 with engine off and 12 with engine running. Perfect Pass was not getting 12 volts at idle and cutting off. Found you could disconnect the purple wire and the gauge would read 12 volts with engine off. Purple wire goes to Coil and Alternator. Tried tracing wires and ground connections for two days and still could not find problem. I installed a 40amp relay on the back of the engine near the circuit breaker. Used the purple wire from the switch to turn the relay on to power the Coil and exciter for the Alternator. Then I added a second relay behind the dash for the Perfect Pass and depth finder. Used the ignition switch circuit breaker as a power source and a wire from the switch to turn the relay on. I added a 10 gauge ground wire from the battery to a ground block behind the dash and grounded all my accessories there. Now the gauge reads 12 volts engine off and 13.5 engine running. Perfect Pass works flawlessly.

JimN
05-10-2009, 12:37 PM
My 87 prostar started reading low voltage at the gauge. Usually about 10.5 with engine off and 12 with engine running. Perfect Pass was not getting 12 volts at idle and cutting off. Found you could disconnect the purple wire and the gauge would read 12 volts with engine off. Purple wire goes to Coil and Alternator. Tried tracing wires and ground connections for two days and still could not find problem. I installed a 40amp relay on the back of the engine near the circuit breaker. Used the purple wire from the switch to turn the relay on to power the Coil and exciter for the Alternator. Then I added a second relay behind the dash for the Perfect Pass and depth finder. Used the ignition switch circuit breaker as a power source and a wire from the switch to turn the relay on. I added a 10 gauge ground wire from the battery to a ground block behind the dash and grounded all my accessories there. Now the gauge reads 12 volts engine off and 13.5 engine running. Perfect Pass works flawlessly.

The purple wire goes to the coil and alternator but it comes from the ignition switch and that's where you need to look at some problems. You were trying to feed more accessories than the wire was sized for and that caused voltage drop.

boyd
05-10-2009, 11:27 PM
If you need a new guage let me know. I bought one for 91 prostar 190. It is the newer type.
I bought it about 6 months ago from skidim. I think they cost about $80. We can check the part and price. Let me know and I'll sell it much cheaper. I sold the boat and never replaced it.

boyd