PerTronix Coil - Losing spark

[NicksterFL]

Ok. I have a Mercruiser 3.0 that is having some issues after running on plane for awhile then backing down to idle. The engine will start missing and eventually die. I noticed if I opened the engine cover, it sometime won't die and recover then I can take off again.

Just now i was out in the river and ran 3,500 RPMs for about 35 minutes, then backed down to idle/no wake zone and the engine died. I checked for spark and I had no spark.

felt the coil and it was hotter than hell. We sat a bit and tried to start and it sputtered, but still a very weak spark. I poured a little water over the base of the coil and shortly it fired right up and we ran again for another 20 minutes or so.

Maybe I have the wrong coil?
PerTronix 40611 Flame-Thrower 40,000 Volt 3.o ohm Coil
PerTronix 1146A Ignitor for Delco 4 Cylinder

this issue is driving me nuts.

 

[thumpar]

If you are running a full 12v to the coil it should be the correct coil.

 

[NicksterFL]

how would i check that? someone else installed this coil and electronic ignition.

 

[WIMUSKY]

I used a Pertronix Igniter lII in a car with an Accel Super Coil. I had a ballast resistor between the coil and the dizzy that I had to remove and tie the wires together. I removed another wire going to the fuse block, brown I believe. The instructions were thorough. Which Igniter are you using? I think they had issues with the first one....

 

[NicksterFL]

this igniter: http://www.amazon.com/dp/B000JUXGAC/

 

[NicksterFL]

I just put a voltmeter on the + and - of the coil while the engine was running on a hose, and i had about 4volts.
Is that right??

 

[Eric 3.7LX Alpha 1]

Test with the red meter lead on the (+) of the coil and the black meter lead to a good ground not on (-) on the coil

 

[NicksterFL]

ok. I did this and got around 10.5 volts.
this is while running on garden hose/muffs. It always runs fine on hose. it's after I run for 20minutes under a load it seams.

 

[achris]

I just put a voltmeter on the + and - of the coil while the engine was running on a hose, and i had about 4volts.
Is that right??

No. You need to check between the coil + and a good ground. If you're not showing battery voltage (with the engine running that should be around 14v), then run a wire directly from the battery and see how that goes. If you have electric choke on the carb, then run a wire directly from the purple on the carb to the coil +....

Chris.......

 

[NicksterFL]

with the engine running, i'm only getting 10.5v on the + side of coil and grounded to battery.

 

[achris]

Sounds like the resistance wire is still in play. Just run a new wire from the choke to the coil+... (if you have electric choke). If you don't, you are going to need to cut into the wiring harness and run a new wire from fairly close to the main harness plug. As you haven't given a year or serial number I can't tell you what colour wire in the loom to look for.

 

[NicksterFL]

No Title

Thanks achris. She's an oldie. 1971 Mercruiser 3.0. I don't have the serial number (tag is gone).

The wires have faded so the color may be off. Take a look at the attached photo.
Top left nut is +.

question: if i've been running the engine with this coil and resistance wire attached. will this cause the symptoms i've been having? and has it compromised my coil in any way you think?

after watching this video (start it at around 0:55) you'll notice his Resistance wire is almost same color as one of the wires on my coil +.
https://www.youtube.com/watch?v=jxrhgUa11-M