CliffA
Well-Known Member
- Dec 29, 2009
- 4,712
- Boat Info
- 2001 Sea Ray 340DA
Name: 'Happy Place'
4.5kW West. Generator
Purchased Nov. 2014
Fresh Water Use
- Engines
- Twin Merc. 6.2L (MPI)
640 hp (Total)
Raw Water Cooled
V-Drive Transmissions
I hate to keep sending you back to do more testing but lets make sure the coil works. Since it is loose, you can do it off the boat with a car battery. Just put 12 volts to the + side of the coil and connect a ground wire to the - side that you can use as a trigger. Connect the spark gap tester to the - side of the battery and strike the ground wire from the coil to the same ground. When you do that the coil spark gap tester should really light up.
That way you can clearly determine the coil status and visually see spark gap tester light up. Mounting should not make a difference but this test will clearly show you whether or not that is an issue.
It is a good idea to be using six feet of wire or so....throwing sparks around a wet cell battery is never a good idea.
Once we have confidence in the coil and the spark gap tester, we will circle back to the ignition module. In order to trigger the coil, the ignition module "senses" a ground connection via a Hall Effect field. Think of it as a magnet passing close to another magnet. This signal is amplified (that's where the word came from) internally in the ignition module and used to trigger the coil. By intermittently grounding the wht/grn wire, you effectively create the same effect without the distributor pickup in the circuit. The fact that you got a very weak spark when you did the test means we need to eliminate the coil as a problem.
-JD
great minds must think alike.......i actually did this last night....i used the ohm meter to check the primary and secondary windings of the coil....they were in spec....the primary windings showed .6 ohms and the secondary showed 10,500 ohms.....the spark gap tester i had does not have an adjustable gap so yesterday i bought a new tester that does have an adjustable gap....i set the gap to around 1/4".....i checked the coil wire and had around 286 ohms of resistance so i think the coil wire is OK...then i disconnected all wires to the coil and ran a direct wire from the battery + terminal to the coil + terminal......i inserted the new spark tester into the HT coil wire and clamped the tester to a good ground source (one of the exhaust elbow studs)....then i used a jumper wire to ground the - terminal of the coil.....there was always a good, strong spark on the jumper wire when i touched ground....about every 3rd or 4th time i touched ground with the jumper wire i would get spark from the coil on the tester....the spark was long and thin...it was hard to tell the color of the spark but it looked like it was white....definetly not blue and as i said the spark was very thin.....thinking i may have spark now i hooked everything back up and left the coil wire connected to the tester and the ground source....i turned the key to the 'run' position and used a jumper wire at the slave starter solenoid to crank the engine over as i watched for spark on the tester....there was no spark at the tester as the engine was cranking....not even the thin spark i saw with the coil isolation testing....
cliff
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