Electrical problem ?

[crgross1]

This is a real "duzzy"<br />A 1997 Mercury OB 150HP Model# 1150422TD <br />Serial # 0G530666<br />This engine cold starts fine and warm starts fine most of the time but sometimes:<br />After it warms up and is turned off, then you attempt to restart it there is no reaction when the key is turned to the start position. It reacts like the battery is totally dead - which it's not. <br />Other pertinent info when this occurs:<br />1- You can try starting it again and sometimes it will start and sometimes not.Eventually it will restart.<br />2- Gauges all fall to zero when the key is turned to start.<br />3- All guages go crazy after restart.<br />4- Ignition switch, kill switch, engine control, including neutral safety switch and battery are all new.<br />Please help with this gremlin - we are at our wits end trying to solve this problem.

 

[chuckz]

Re: Electrical problem ?

You have a loose wire or corroded connection between the battery and the engine. Remove, clean and reconnect the hot and ground wires, at both ends, interconnecting the motor and the engine.

 

[crgross1]

Re: Electrical problem ?

AND<br />If cleaning all the connections between the battery and the motor as well as all the other connections on the motor doesn't solve this problem what is the next most likely culprit ?

 

[chuckz]

Re: Electrical problem ?

Replace the cables between the battery and the engine. When you turn the key and everything goes to zero, all the voltage is dropping between the battery and the engine instead of supplying the gauges. Put a DVM at the battery side of the starter solenoid and measure the voltage while cranking. If it goes to zero, you have a bad cable.<br /><br />OR <br /><br />You have a dead short to ground on the starter side of the starter solenoid. I would think you would see smoke if that was the case. If you can find an automotive clamp on amp meter so you can tell if the current is flowing through the starter. If it is, you have a bad starter, if it isn't you have a bad cable. If you're not sure, the cable is cheaper to replace than the starter.

 

[crgross1]

Re: Electrical problem ?

Thanks for all the good advice.<br />I'm curious why you never mentioned the voltage regulator or the starter solonoid as possible culprits.

 

[crgross1]

Re: Electrical problem ?

LI Chuck<br />I'm curious why you never mentioned the voltage regulator or the starter solonoid as possible culprits.