mid 80s 150 mercury voltage problem?

Brett j

Recruit
Joined
May 16, 2014
Messages
3
I bought an engine and finally got it on after many mounting and steering adjustment problems but it is now successfully on and cranks right up and purrs like a kitten. When I bought the motor I had to transport it in the back of my truck. Laying it down on the "elections side of the motor with plenty padding supporting the head and a piece of wood under the lower unit. Had to keep it in the back of truck until the lifting ring came in. I broke the starter solenoid while installing it. Went to napa and got a replacement marine solenoid. I have the correct one on the way. Seems to work just fine. Like I said it cranks right up. All cylinders are reading 108-111 compression. Darn good right. I saw all plugs firing. This was all done before I bought the motor. My problem is when you get past idle speed and begin to give it throttle it bogs down. Wants to kill. But never does. One thing I have noticed is that when the motor is running the volt meter is reading less than 12 volts. When you kill the engine the bolt meter reads 12.5. I am frustrated and need some ideas.
 
Joined
Oct 11, 2015
Messages
7
The stator feeds the rectifier witch then charges the battery. You may be having a stator problem. You should check out the two yellow stator wires some of the old Mercury's had bad insulation on those wires and could be bare and shorting. They go from stator to the rectifier
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,146
Yes, likely you have a bad rectifier. Sort that out first. If the bogging is still an issue, clean the carbs.
 
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