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3.0 litre Merc no start/no spark...HELP !!

taperk600

New member
Well, we are getting our "old" boat ready for sale since we bought a newer and bigger boat 2 summers ago...... and I have no spark from the coil. Any ideas ???? What to test ?????

A little back story.........The old boat is a 1989 Wellcraft 170 classic with a Merc 3.0/alpha 1 set up. We bought it in the fall of 2009 and it had ethanol fuel related issues when we got it. It ran, but not the greatest. So for the 2010 season, we did a complete tune-up, flushed the fuel system, & had the carb rebuilt. We used it for about an hour, maybe 2, after the work was done and the boat ran 100%. Then we bought our 24 ft Chaparral since it was obvious the 170 was too small for what we wanted it for --- diving off from. So we put it to bed that fall (2010) --- winterized, shrink wrapped, etc. with the intent of selling in the spring (of 2011). Well, we never got around to getting the boat unwrapped and ready for sale last season due to too many other things and a busy work season. So, I made myself get to it early this season before I got too busy again......

NOW..... we got the boat unwrapped, cleaned up, and the battery charged up. It turns over, is getting fuel, but I have no spark from the coil. I am not experienced with points/condensers ignition system, but like I said above, all was new with about an hour or 2 of use. To confirm -- new cap, rotor, wires, plugs, condenser, and points.
Points are not fused shut and are not corroded.
No corrosion inside the cap either and rotor looks new.
I do have 12v at positive of the coil with key on.

Appreciate any and all suggestions and help !!!
 
Is there a kill switch? Make sure it is on and not in the off position. Where are you checking for spark? The coil HV output to the dist. cap can fail easily. Install another one or take a plug wire and install it in place of the coil wire to see if it will spark. Try disconnecting the condenser...they can short out easily and kill the ignition. If it starts install a new the condenser. Also make sure the shifter is in neutral and check that the shift/ignition kill switch is working. Get back with the solution.
 
Is there a kill switch? Make sure it is on and not in the off position. Where are you checking for spark? The coil HV output to the dist. cap can fail easily. Install another one or take a plug wire and install it in place of the coil wire to see if it will spark. Try disconnecting the condenser...they can short out easily and kill the ignition. If it starts install a new the condenser. Also make sure the shifter is in neutral and check that the shift/ignition kill switch is working. Get back with the solution.

Checking for spark first at the plugs and then directly off the coil lead. All wires are brand new, but did check resistance to make sure something strange hadn't happened...tested ok. No tether type kill switch and neutral safety switch is functioning.

Will try the condenser idea...haven't done that yet.

the points are glazed over, can clean with sandpaper of file for testing

No... they are clean. Checked for that already.
 
Checking for spark first at the plugs and then directly off the coil lead. All wires are brand new, but did check resistance to make sure something strange hadn't happened...tested ok. No tether type kill switch and neutral safety switch is functioning.

Will try the condenser idea...haven't done that yet.



No... they are clean. Checked for that already.

Ayuh,.... Put a multimeter on 'em,...

I'm with BD, ya need a New set.... Time kills 'em more so than hours of run time...
 
Fastest test, is to use a jumper wire from battery positive to the positive of the coil and try to start. If it starts then the ignition system is not the problem. If it starts you have to remove the jumper wire to shut it down.
 
Bad condenser.....THANKS GUYJG for the suggestion. Wire was pinched very slightly in cap, but obviously enough to short it out.

All set now.....thanks to all !!!
 
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Bad condenser.....THANKS GUYJG for the suggestion. Wire was pinched very slightly in cap, but obviously enough to short it out.

All set now.....thanks to all !!!

Glad you go it working, I had a problem very similar to this. Had to sand every connection down and check every wire before I found the culprit.
 
YeeeeeHaaaaa I win!

Yes you do !!

I new the points were good !!!!

Thanks again to all that aided and gave suggestions !!! I stumbled on this site by accident, but think I will stick around and see what else I can learn.....or possibly, maybe even I can lend a helping hand to someone too sometime.....
 
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