'90 Mecury 115 Battery Related?

[goodeman]

It will become very obvious to you that I know very little about Outboard engines. I have a '90 Mercury 115 on my Astro F/S. Monday, I was running along about 25 MPH when I lost power and the engine shut off. I was able to re-crank the engine, but it again shut off after about 5 minutes. I looked at the cranking battery and there was some corrosion on the positive side. I cleaned as best I could. I cranked and headed slowly back to marina. Made one more stop to jump in the water. This time, the engine wouldn't crank so I jumped off with TM battery. Other thing, was that the + post of cranking battery was very hot. <br /><br />Does this sound like a battery problem? Or an alternator (does this motor even have one)? I was puzzled why the battery drained while motor was running. Any suggestions would be appreciated.

 

[The Marine Doctor]

Re: '90 Mecury 115 Battery Related?

The Stator is the most suspicious here. It charges the battery and supplies the current for the igntion.<br /><br />TMD

 

[marinegrh]

Re: '90 Mecury 115 Battery Related?

your engine will run even without the battery, its only used for cranking purposes, then once the engine is running, the stator puts out ac voltage to a regulator rectifier that converts it to dc voltage to keep a positive charge on your battery, unless you have a dfi or efi engine, your engne is not relying on that battery but only for startup. your stator also produce ac voltage for the ignition system, sounds like you have a bad stator, and cranked the engine so much you drained the battery down, <br /><br />keep us infoed<br />marinegrh@bellsouth.net

 

[Skinsk]

Re: '90 Mecury 115 Battery Related?

You may or may not have a bad stator. Don't yet jump to conclusions. <br /><br />First make sure you have no water in the fuel. Make sure the kill switch is not pulled halfway. <br />Make sure you do or do not have spark.<br />If no spark, it could be stator, or switchbox (I can't remember when the motors went to CDI ignition). <br />The stator has two different sections, one side produces AC voltage to charge the battery. The other part produces the voltage that fires the spark plugs. These two things just happen to be in the same place, but are independent of one another.<br /><br />Also make sure your battery connections are good and tight. Loose connections increase the resistance at that point, and therefore increase amp drawn, which increases heat and kills the battery faster (also could cause the volage regulator to go bad due to voltage spikes while the motor is running). <br />And don't run your motor without a battery connected or you will blow your voltage regulator.<br /><br />Yowza..My post makes it sound like I'm in a bad mood..<br /><br />Scott.

 

[goodeman]

Re: '90 Mecury 115 Battery Related?

I appreciate the information. Looks like I need to take it in!

 

[greasemonkeyozi]

Re: '90 Mecury 115 Battery Related?

Goodeman, where exactly do you live in alabama? I live in Oneonta, Al. If you live close to me, dont exactly take it to a $55.00 an hour mechanic just yet. Email me at Greasemonkeyozi@yahoo.com and tell me whats up.