2800 SCR 4.3 V6 ignition problem

[marcucho]

I am copying this post from my post on Mercrusier FB.. looking for help

First part
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Working 4.3 v6 vortec just stop ..turning no running…
My faithful (port side) engine just stopped working at the ramp. It started for 3 or 5 second and then died. Could not get to start again.
Let me start saying that I replaced coil, distributor cap, rotor, ignition sensor (distributor), spark plug cables. It actually ran fine with the water hose on the trailer .. no problem at all.. it was just when it got to the real deal on the water

1) Plenty of Gas. I can even see gas getting to the carburetor .. even used starting fluid.. turning but not running.
2) Checked the following

1. Kill safety switch (I replaced with a new one .. I had a spare one)
2. I checked on current at the key switch, then following to the kill safety switch and check at the ignition coil. 12V all the way
3. Tried the ignition module from my starboard engine … no luck.
4. Tried another ignition coil. no luck
5. changed the ignition sensor in the distributor to the old one .. no luck
   
6. I checked on the grey cable (for the tachometer) it is connected .. so, it is not grounded
7. I check on the green/white cable from the ignition module (12V) no problem from there... Like I said before I even tried with a known working ignition module.
8. What I cannot find is the Neutral Safety switch that supposes to be at the gear linkage This is a Bravo 2 I think that the switch is on the level control itself

I also checked on the 50 Amp breaker if it was triggered.. nothing there either
Getting a tester to connect to the spark plug to check if I have spark .. if I have spark .. well that it’s something … but I believe that I will not have spark…

suggestion…?


PS. Plenty of Gas, no gas problem. fuel filter clogged, fresh gas. Fuel/ water filter new .. The problem is electric

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PART 2 (updated from last weekend)
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Ok last Sunday results.

1 All connection from the ignition key switch to the coil were rechecked. 12 Vol all the way to the Coil
2) Checked the spark from the coil to distributor = Strong spark
3) Checked the spark from distributor to the sparkplugs = Strong spark.
4) Checked all connection cables from distributors to ignition module = Everything is plugged right and the correct sparkplugs.
5) Checked pressure cylinder #1 and set TDC = Pressure 120 and made sure that Cylinder 1 was TDC
6) Opened NEW distributor cap to check were the NEW rotor is pointing at TDC. It was pointing to cylinder 6
7) How the time got moved just because replacing new sensors, distributor cap and spark plugs cables … Do not know …
8) This engine was the faithful one never had problem with it, actually started fine after I put the new parts (rotator, distributor cap, ignition sensor and cables) , problem started after it hit the water
9) Set the time back to 1 when TDC .. I can tell the bolt at the distributor was tight as hell so it did not move ..
10) tried to start the engine and just turn over, gasoline getting to the carburetor (actually sparkplug was gasoline wet when I pull the spark plug for Setting TDC ).

Going to turn the engine few times to check if at TDC the rotor still set at location #1 at the distributor .. if not we may assume the timing chain jumped?
Crazy thing is that this engine only have 248 hours.. for a timing chain to jump.. any other suggestion ?

I checked on the 50 AMP breaker, but I think that if the breaker is triggered nothing would work on the engine .. meaning I would not be able to get spark on any sparkplugs ..

For a engine to work just need spark and gasoline and I have both .. I also checked on the oil sensor unit that may shut down the fuel pump .. but I do get gasoline so oil sensor unit theory out the door..

I do not have the neutral switch like alfa1 , I have it on the helm level unit ..and I assume that if the neutral safety switch is bad I would not be able to get spark at the coil and sparkplugs …

Any Idea that is not kill switch (tested), ignition module (tested), coil (tested), sparkplug cables(tested), ignition sensor at distributor (tested) ? Does the mercrusier 4.3 v6 have any other fuses of switch that may create this situation .. ? I am open for any suggestion at this moment ..

Thank you guys