Logo
FULL SITE MENU

Mercruiser 3.0L will not start

K

kingbruiser

New member
Cannot prime carb with throttle, and no spark. I have been trouble shooting with no results. What I have done are as follows, drained fuel tank,refill,new gas lines all the way through to fuel pump, new water fuel seperator filter, new fuel pump filter, carb filter, new battery and coil. Pressurized fuel tank and have gas at fuel pump. I did a complete tune up last July new plugs cap, rotor, points, wires, condenser, rebuilt carb, new drive hub, water pump, timed and dyno. Ran out great. Only 40 hrs last summer on motor. I cecked points and they open. Tryed pouring gas in carb- no fire. I took off coil wire from cap and could not get a spark while trying to arc it on block. changed coil again with no luck. Tryed a lead wire from + battery post to + coil with no spark. checked reset button . Turns over slow even with new battery which checked out at 12.6v. Checked coil and it had 10.63 on resistor. I'm wondering if ther might be a problem with the neutral switch on the shifter also or the key switch. The starter is about 3 yrs. old, has no obvious clicking . Checked all connections on wires, cleaned up . If any one has a suggestion as what to do next, it will be much appreciated. Thanks.
 
Ayuh,.... Do the points close,..??

I'd replace the points, 'n try it, they fire the coil,....

Points are also an Annual maintenance item,.... regardless the hours run,....
 
I would suggest looking at the start assist relay it should be back by the breaker switch on the motor its little square thing with like 4-5 wires coming off of it one of the terminals could be bad you can check it with a volt meter.... My friend had a problem on his 3.0L with the same symptoms as described and that was what it was.... Just a thought maybe
 
Thank you. I checked it out and it was ok. I started again from scratch. began with clean empty tank, new fuel, filters, water fuel seperator, points, plugs, cap, rotor fueses, new egnition, a couple of new connections on wires from starter to coil. I now got a hot spark at coil. Still turned over slow. Took out the starter and load tested . It was bad. Put in new starter. Adjusted electric choke, pumped handle,and it started on first try. Double checked the dwell on points which i had preset at .o18 and have 23 degrees. Set the timing. Adjusted the air-fuel to obtain the highest rmp and re checked timimg. The end result is I now have a good rumnning engine. Addinitionaly I want to thank XxstarXx, CHawk and bondo for their replies.
 
Last edited:
Back
Top