Batteries won't stay charged

Joined
Mar 5, 2014
Messages
8
I have a 1983 90hp evinrude M#90TLCOS. I am constantly having to charge my batteries every time I use my boat. Where or what should I check first. Thanx
 

Will Bark

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Aug 1, 2010
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1,470
Re: Batteries won't stay charged

Using a multimeter check your voltage at the battery without the engine running, then check it again with it running; voltage should read higher than before. If not, then suspect you rectifier/regulator. But first make sure all connections are clean tight and shiny bright. Others will probably chime in with more thoughts. Good luck
 

Bosunsmate

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Apr 7, 2012
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Re: Batteries won't stay charged

Check whether your tach/rpm is working or not, if its not suspect the rectifier as mentioned by Will.
Ive found the stators are pretty tough on these so its normally something other than that.
The battery will slowly climb up while running, ive forgotten what it peaks at.
 

tblshur

Senior Chief Petty Officer
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Aug 24, 2011
Messages
688
Re: Batteries won't stay charged

Knot , welcome aboard! if you have a 12 volt test light, you can disconnect the positive battery terminal then connect one end of test light to positive battery terminal . the other end of test light to the positive wire you just took off battery, if the light burns you have a current draw from battery, then disconnect the positive (red) wire from rectifier, if light goes out rectifier is bad. good luck:joyous:
 

boobie

Supreme Mariner
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Nov 5, 2009
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Re: Batteries won't stay charged

Have you had the batteries load tested lately ?? Chance they could just be bad but the load test will tell.
 

Vic.S

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May 4, 2004
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Re: Batteries won't stay charged

I have a 1983 90hp evinrude M#90TLCOS. I am constantly having to charge my batteries every time I use my boat. Where or what should I check first. Thanx

Thats a model number for 1985!

Use a multimeter as Will Bark suggests. With the engine running and some revs on the volts should rise eventually to a bit more than 14 volts if there is a rectifier regulator fitted. If just the plain round rectifier then they will rise even higher.

But if they dont it may be a defective rectifier or a defective battery.

Best plan is to take the battery off the boat and charge it fully with a good automatic charger. Aim to charge until the volts are 12.7-12.8 12 hours after stopping the charge. If you cannot get to 12.7 ( rested for 12 hours) the battery is probably defective. Then monitor the volts for as long as possible. They will fall fairly quickly at first but a good battery will take several weeks to fall below 12.6 volts.

However only a proper battery test will really tell you if the battery is truly good or not.
 

Vic.S

Rear Admiral
Joined
May 4, 2004
Messages
4,690
Re: Batteries won't stay charged

Knot , welcome aboard! if you have a 12 volt test light, you can disconnect the positive battery terminal then connect one end of test light to positive battery terminal . the other end of test light to the positive wire you just took off battery, if the light burns you have a current draw from battery, then disconnect the positive (red) wire from rectifier, if light goes out rectifier is bad. good luck:joyous:

It is not a good idea to disconnect the battery while the engine is running. It could cause a voltage surge which will blow the rectifier
 

tblshur

Senior Chief Petty Officer
Joined
Aug 24, 2011
Messages
688
Re: Batteries won't stay charged

Knotquilty954, Vic.s is exactly right you never want to disconnect battery with enjine running. i didnt make that clear in my post. you can also use the amp selection on multimeter to do the same thing.thanks Vic.s.:)
 
Joined
Mar 5, 2014
Messages
8
Re: Batteries won't stay charged

You guy's are awesome!!! In regards to my battery issue. I installed a $4 dollar full wave rectifier from RadioShack rather than the $100 dollar factory part. Was this a good choice or should I just spend the extra money? So I have the engine running ,decide to put it in gear and notice my prop. didn't spin. Wtf!! I just replaced the tilt tube, helm,&steering cables. What do I do now gentleman? Where or what do I check first? Thanks for your input
 

coolbri70

Lieutenant Commander
Joined
Oct 6, 2011
Messages
1,554
Re: Batteries won't stay charged

I would start a different thread for those issues, as different people who know more about that subject may respond:eek:hwell:
 

emdsapmgr

Supreme Mariner
Joined
Dec 9, 2005
Messages
11,551
Re: Batteries won't stay charged

Regarding the shifting problem: disconnect the shift cable at the engine. Start the engine and try to shift the lever by hand. If it shifts ok by doing it manually, it's just a cable adjustment problem. To adjust, put the engine manually in forward, then shift the control box to forward. Look to see how close the eye of the cable end matches/aligns to the shift lever bolt. Turn the turnwheel on the engine end of the shift cable to make sure the cable end eye perfectly aligns to the shift lever bolt-then bolt it in place.
 

boobie

Supreme Mariner
Joined
Nov 5, 2009
Messages
20,826
Re: Batteries won't stay charged

Agree with the above. Start a new thread for the shifting problem. You'll get better answers.
 
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