same old 90 hp merc

[ocean_sport]

When engine is running at 1500rpm, I am getting a reading of 12.8, 12.7 volts at the posts on a brand new battery.<br /><br />Shouldn't the readings be higher? 14, 14.5???<br /><br />could that have anything to do with why it starts so poorly? no hot spark.

 

[corm]

Re: same old 90 hp merc

Hi,<br />Your rectifier may have one side burnt out.<br />This wont effect the starting unless your battery is low on charge.<br />What does it read at 4000 RPM. You will have max charge by then.<br />...have fun...corm

 

[Walter]

Re: same old 90 hp merc

I'm no expert on Merc's outboard charging systems...but it sure seems to me that you should be seeing a much higher battery voltage at 1500 RPM than 12.8 volts. <br /><br />I don't know what you mean by "starts poorly"...but if your battery isn't charged properly...you certainly won't get the cranking RPM you'd should expect with a fully charged battery.<br /><br />Walt