Battery keeps going dead even after i put new stator on' could it be the power trim

[melissagrawe]

I have trouble with my battey always going dead. I have redid all the wiring on the motor with brand new wire harness. Could it be possible that i don't have the power tilt/trim wiring messed up. I know the battery is good but i can't have the radio, nav system and power trim hooked up or battery will go dead. I have a mercury 115hp 1978 outboard

 

[DamianJP]

Re: Battery keeps going dead even after i put new stator on' could it be the power tr

Hello melissa

Check your Rectifier. Mine was doing the samething and when I replaced the rectifier all was good.

http://1manual.com/Mercury manuals/Service Manual PDFs/TwoStroke/13645_2/2b.pdf
Should be on page 2B-17 for the rectifier test. I think you have the 3 post rectifier.

Mabey J-Martin can chime in, he's awesome with the electrical stuff on outboard(s).
He told me of a replacement that cost alot less than the $30-$40 OEM part. Mabey it can work for you too. Crowley marine shows your OEM replacment as the same as mine of my XR4 89' , P/N 816770T so this might be a good replacement but wait for the experts to give the green light. Don't want you to screw something up because of me.

Check it out $3-$5 too
http://www.mouser.com/ProductDetail...=sGAEpiMZZMtcLAek5QF0i29EdKsLUhPgK25hIs5GSO0=


BTW check here for a specific manual for your engine you can download. It is big though.
http://forums.iboats.com/showthread.php?t=415403

Lemme know what happens,
DamianJP

 

[Silverbullet555]

Re: Battery keeps going dead even after i put new stator on' could it be the power tr

How long does it take to do dead?

One of those systems is drawing the current when off.

I have my battery going through an off switch so when the boat is in the garage, the battery is disconnected.

 

[Silvertip]

Re: Battery keeps going dead even after i put new stator on' could it be the power tr

The radio draws current even when off because the station memory and clock need to be powered. Granted, the current draw is low and should not kill the battery in a short time. If the trim wiring was messed up you would hear the motor trying to run. If it works ok that's not the problem. Don't know what your NAV System consists of but disconnect the feed to those items one at a time to isolate which one is causing the current draw. Have you had the battery load tested? Just because it's charged does not mean it's good. It must be able to actually deliver current iinto a given load. It may measure 12.6 volts but the minute a load is applied it drops significantly which is indication the battery is on its last legs or has already lost one. You might try hooking everything up and then disconnecting the rectifier. If the battery stays up the rectifier is bad.

 

[j_martin]

Re: Battery keeps going dead even after i put new stator on' could it be the power tr

First, take one terminal off the battery (with the engine off, of course) and tough it to the battery post. If it sparks, you have a problem. Find it and fix it.

Then check your battery voltage with a multimeter. It should be between 12 and 12.5 volts with the engine off, and over 13 with the engine running a little over idle.

If the running voltage is low, the rectifier is likely bad. You can remove it and test it with an ohmmeter. There's a sticky on this site for that.

The Mouser rectifier is strong enough to provide forgiveness for sinful acts like not maintaining the battery connections. It's also cheap, but needs some rigging to install.

hope it helps
John