Not firing

[Proline3250]

I have a 1998 pro line 3250 with 7.4 MPI the port engine was not firing replaced the coil and the module inside of the distributor the distributor cap and rotor button started right up no problems three days later no fire again checked both coil and module seem to be fine Took the coil wire off of the starboard engine which runs still no fire at coil wire I have power at both wires with the ignition in the on position at both the distributor and the module inside of the distributor cap disconnected the tack still no fire at the coil wire I am perplexed. Tachometer doesn’t show any movement when cranking the engine.

 

[alldodge]

Motor serial number?

Being a 98 I'm guessing its a MEFI 3 with EST ignition
Have you checked for codes?

 

[Proline3250]

S/N 0L008874 and not yet on the check codes just trying to not get the $110 an hour guy involved until I had to.

 

[alldodge]

Shows L29 and should have the rare MEFI 2

While cranking see if you can see 300 rpm on the Tach. If not disconnect the gray wire off the rear of the Tach

Can see if there are codes with a resistor LED of a digital multimeter with a tone ohm setting. Need to count the flashes of beeps when ignition is turned ON.

 

[Proline3250]

No movement on the tack whatsoever and I did disconnect the gray wire this morning and tried it again no change.

 

[alldodge]

Move the ECM from the motor which will not start to the motor that will start.

 

[Proline3250]

I did that also no change I have left from where the boat is I will be back with the tester tomorrow. It does also have a B&G engine computer hooked to it also.

 

[alldodge]

Don't know what a B&G is

 

[Proline3250]

Basically it’s a electronic gauges shows RPMs engine temperature fuel consumption voltage engine hours total fuel consumption things like that

 

[alldodge]

No spark

Replaced everything in and connected to the distributor. Swapped ECM and troubled motor ECM runs on other motor. Disconnected the Tach and still do not have any spark. Have 12V at the coil and wires between coil and Dizzy are good.

Either the Tach wire wire is shorting out somewhere along the harness, the rotor isn't turning, or the Dizzy module just replaced is bad.

 

[Proline3250]

Rotor is turning and I went back and got a second dizzy and checked it still no spark where does the gray wire connect from the tach to where on the motor??

 

[alldodge]

The Gray wire changes to White at the fuel injector harness and then goes to the coil connector next to the Red wire

 

[Proline3250]

I wound up pulling both distributors I put the distributor out of the motor that would not run in the motor that would run and it fired right up I cut it off and tried to restart it and it would not start must be the small coil inside of the distributor