No spark after spark plug wires wrongly placed… mercruiser 3.0

IselaLuv

Cadet
Joined
Jul 5, 2022
Messages
27
I couldn’t get the darn thing to start, didn’t realize my spark plug wires had been placed in the wrong sequence by mistake I cleaned the carb, did compression test… only to retrace back and find my blunder. I changed wires, cap n rotor and sparks again. I get no spark now. Has this ever happened to anyone and would placing the wires out of sequence on the cap could have messed up something else? If so what do I check? When I first replaced it all I turned the key and my spark detector had light but as I tried again it went to just a blink here and there. I have a 2002 sea ray wih a 3.0 mercruiser.
I have the service manual now, and thanks to that I realized my wiring order was wrong. I had it on 1432 when it’s 1342…
I really appreciate all of you guys, thanks in advance for your replies.
 

airshot

Rear Admiral
Joined
Jul 22, 2008
Messages
4,975
When I had my 3.0, first thing I did was using a felt tip marker, wrote the cylinder number on each boot and the cylinder number on each cap post. When I replaced them just copy the numbers onto the new cap and wires. Saves a lot of headache like you are experiencing
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,421
only to retrace back and find my blunder. I changed wires, cap n rotor and sparks again. I get no spark now.
It sparked again, then you say it doesn't. Gets confusing
What else did you do to any of the wires to the Distributor?
 

jimmbo

Supreme Mariner
Joined
May 24, 2004
Messages
13,421
Something is preventing the Ignition System from producing sparks, or sending the sparks to the plugs. Remove the High Tension wire coming from the Coil to the distributor, and check for spark. It needs to be good enough to jump a 3/8" gap. If it does, make sure all the Wires are secure in the cap, and that the wires are going to the correct cylinder, not just in the correct order. Being an I/O I would recommend that the Spark Tester be of a type that is sealed to prevent any chance of an explosion from gas vapour in the engine compartment. However, don't you those useless Neon type spark testers.
 

alldodge

Moderator
Staff member
Joined
Mar 8, 2009
Messages
41,870
Don't know the serial number but motor probably has a EST Dizzy

Have you checked for 12V at the coil and Dizzy?
Have you done the test on the Dizzy parts as listed in the manual?

Checked the rotor to make sure the electrical tip has not come loose or broke?
 

airshot

Rear Admiral
Joined
Jul 22, 2008
Messages
4,975
Some years back had a neighbor that ran into a similiar issue. Motor was working but needed a tuneup. Replaced all plugs, wires cap, rotor etc. After all was back together he had no spark. After hours of taking apart and putting back together, testing and lots of cussing, he finally realized he forgot to install the new rotor in the distributor !!!!
 
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