Input voltage low

[Cool It]

hello ,<br /><br />Yes it is me again ,I know I have alot of question -- but there is always something to fix or improve with all my little things that are not always right my boat is still running nice and looks great to ( if I could figure out how to post the picture I would) but any way my new question is when I have my hummingbird matrix system on and I start the boat the system flashes on the screen INPUT VOLTAGE LOW - now I assume this has something to do with my battery or charging system But it seems to start fine so what is this telling me?????<br /><br />Thanks<br />Cool It

 

[tommays]

Re: Input voltage low

it is doing this because the voltage during starting is droping below a level the hum unit thinks is nessary<br /><br />the only way you can check you boat is with a meter connected to the battery <br /><br />a new battery will hold about a 12.8 volt charge with everything off<br /><br />you need to see how low the voltage drops on the meter when you are cranking the motor<br /><br />my last battery was 8 years old and held a 12.4 volt charge the boat started ok but i felt it was time to go new <br /><br />i have to say that the motor must crank about twice as fast and start much better even thoe the old battery measured ok a 12.4 it was droping much lower when trying to start the motor it just could not pass the amps the starter needed anymore<br /><br />a good chargeing system will measure about 13.8 to 14.4 volts at the battery when the motor is on<br /><br />tommays

 

[Cool It]

Re: Input voltage low

my voltage meter on the dash reads between 12-14 while running but sometimes when I just start the boat it reads about 10 until I give it a quick rev then it sets up in the 12-14 range and stays there-- can this be what the hummingbird is reading and do I need to worry about this.<br /><br />Thanks <br />Cool It

 

[tommays]

Re: Input voltage low

with out a meter pretty cheap at radio shack or home depo for digital readout meter you<br />really dont have good numbers the guage on the dash is not very good for checking if you have a problem<br /><br />tommays

 

[Elk Chaser]

Re: Input voltage low

Fairly normal for a 1 wire alternator to need a jump in RRM's to get the exciter going. If you have a 1 wire altrernator then you are OK, if you have a 2 or 3 wire alternator then the voltage regulator may be going out on you.

 

[Cool It]

Re: Input voltage low

how do I know -- is it just by sight - how many wires lead to the alternator??

 

[Wart T]

Re: Input voltage low

I like to use a stand alone deep cycle battery to run electronics. It gives a good clean power source that isnt used to drive boat stuff. It can serve as a back up to start the boat should it be needed. This way you don't get the voltage drop when starting. <br />I do agree that you may have a problem with the voltage dropping too low when starting. Start with the simple and free stuff first- check all connections including connections on the motor including grounds. Unscrew the bolt that holds the ground cable on the engine and make sure there is no corrosion. Be positive (no pun intended) you have a good clean system. Then you can start looking at the battery or starter as a culprit.

 

[jlinder]

Re: Input voltage low

okdbaldfatguy,<br /><br />I second that. I have seen more problems with corroded terminal wires, loose connections, even battery wires where the wire at the battery terminal was so bad that a big percentage of the strands were broken.<br /><br />Check and clean everything. Make sure it is all tight. Are the terminals making a good connection? This is just good maintenance.<br /><br />To go further, feel the wires near the battery terminal after you start up (if possible to do safely). Are they warm? If so check again. Maybe the wire is going bad.<br /><br />I have also noticed that boats seem to run wiring that is smaller than what I would use. If you are checking voltage when starting, check at both the battery terminals and at the electronics. If there is a significant difference you may want to look into checking the wiring to the electronics.<br /><br />FYI -- I recently replaced my alternator and ARCO, the manufacturer of the alternator, reccomends not using the factory wired voltage sense wire to feed the voltage regulator, but connect the sense wire to the battery, or alternator output. They say their experience is that the sense wire comes from the dash area, and boats after a while develop a resistance in the wiring that makes the charging voltage too high. <br /><br />Hope some of this helps.

 

[Cool It]

Re: Input voltage low

How do I know if I have a 1,2,or 3 wire alternator.<br /><br />Thanks<br />Cool It

 

[Trent]

Re: Input voltage low

Look at the back of the alternator. Count the wires.

 

[Cool It]

Re: Input voltage low

I have a three wire alternator. I do need to rev it when I start to kick it into 12-14 range then it stays there -- is this going to be a problem with the regulator as Elk Chaser said or am I ok. If I need to change regulator is it easily done??? <br /><br />Also a note - my negative battery cable lug/Terminal connector looks like it is slightly cracked -I would like to change the cable but It looks like it runs under the engine where I cant get to it. - can I just change the lug/Terminal Connector and if so do I just do it like any other wire??<br /><br />By the way at this point Im not having any trouble starting the engine!!<br /><br />Thanks <br />Cool It

 

[Dunaruna]

Re: Input voltage low

[How do I know if I have a 1,2,or 3 wire alternator.<br />Thanks<br />Cool It]<br /><br />[Trent: Look at the back of the alternator. Count the wires.]<br /><br /><br />You guys crack me up <br /><br />Aldo

 

[jlshields]

Re: Input voltage low

Cool It, you have a Mando alternator. Your's is acting right. Mine has done that for 7 years now and still running strong.

 

[Cool It]

Re: Input voltage low

Thanks jlshields- and for you dunaruna -I am not a mechanic I am trying to learn what I can as I go --- I thought the wiring might have something to do with an internal thing-- so maybe I will crack you up some more in the future but I am learning quite a bit from this sight and already have done some repairs!!!!!<br /><br />Thanks<br />Cool It

 

[Dunaruna]

Re: Input voltage low

Hey cool It, cool it. No offence intended, Trents reply tickled my funny bone, thats all. I certainly didn't think that your question was unreasonable. Sorry mate.<br /><br />Aldo

 

[Cool It]

Re: Input voltage low

Hey thats all right-- we are all here to learn from each other and enjoy our boating season!!!<br /><br />The name of my boat is Cool It because thats what I always tell my son to cool it -- so he said I should name the boat that! <br /><br />22ft W/A Seamaster 5.0 Merc