Mercruiser 3.7 Starter

[ImperialV184]

Hello, need some help here. Just fishished complete rebuild of my mercruiser 165. I was doing a quick dry run of the engine, no fuel, but using the starter to turn over the engine to verify oil pressure. When I turn the ignition just a bit, it turns then stops. When I give it about 5 seconds and turn off ignition the starter continues to run for a bit. It ieventually stops after about 20 seconds then stops. Seams like relay is sticking but verified hot wire from ignition goes cold when key is off. Something is keeping the relay open and providing power. Checked all working, and two relays. Everything is new, starter, starter relay, ignition switch, coil etc. I did install the after market alternator conversion kit and removed stator and voltage regulator, Everything is new, put the old relay in an got the same response. Have come too far in my own to take it into a shop. Planning on adding fuel and cranking this weekend. Thanks for the asistance.

 

[Bondo]

Ayuh,..... Meter or test light the key switch to see if it's doin' what it's supposed to do,....

Then the slave solenoid, then the starter solenoid,.....

 

[ImperialV184]

Got it, tested the ignition. switch from ignition(yellow red wire). Voltage dropped when key was off. Swapped out the slave solenoid as well, no change. Will check starter solenoid as well. Bummer all are new, starter, slave solenoid, ignition switch. I guess I could have got a bad starter solenoid. I did put a little perfect seal around the starter end where it comes in contact with the block because my old one was fused to it and I was trying to prevent this. Wonder if that is giving me a bad ground, I did verify ground using ohm meter but did not check voltage during cranking.

 

[ImperialV184]

Just an update. We traced it to the starter solenoid. We tapped it with the wooden handle on the handle and it never happened again, must have been some debris in the solenoid that was causing it to hang, will keep my eye on it.