No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

[Rockslide]

I just bought a 1986 Eclipse Mach I bowrider with the Mercury 3.0 140. This boat has less the 200 hrs and was winterized and garage kept for the last 12 years. By that I mean it was left in the garage at the lake house for 12 years without being started. I serviced the outdrive, oil change, thermostate, hoses,and plugs and put fresh fuel in it. The engine turns over with no problem, good and strong. But I'm not getting any spark. I checked if there was spark coming from the coil but no spark. Being this old I bought a new one and still nothing. I traced the wires using the diagram and all connections look good. No cuts, nicks or crimps anywhere. I have 12v to the terminal on the coil but thats where it ends and my hair pulling begins. I'm not a mechanic but have a pretty good grasp on basic electrical.I'm at a loss and running out of season. Any help is much appreciated.

 

[888]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Points replaced?

 

[Rockslide]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

yep. Just did the points and rotor. I put an inline spark tester and now I have spark to the coil and out of the coil. I put the tester inline on the no.1 spark plug but have nothing. Whats next? I fell like I'm running out of season!

 

[888]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

replaced the cap

 

[Rockslide]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

The cap has very little wear. No damage or moisture. I cleaned the carbon off the cap contacts with a dry qtip and it came clean as well as the rotor contact on the cap.

 

[generator12]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

What lies between the coil hi-voltage output line and the number 1 spark plug?

The cap, rotor, and the hi-voltage line from the cap to the plug.

Take your choice.

 

[skyking897]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

I put an inline spark tester and now I have spark to the coil and out of the coil.


What exactly do you mean by you have spark to the coil. There should only be power to the positive side of the coil and spark from the secondary (coil tower) side.
The negative side of the coil is connected in series with the points and condenser, either of which could cause no spark.


I put the tester inline on the no.1 spark plug but have nothing. Whats next? I fell like I'm running out of season!

If you do indeed have spark from the coil tower but not at the spark plugs you either need a new rotor, dist. cap or ignition wires, or E all of the above.

 

[Eric 3.7LX Alpha 1]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Did you pull the rotor out and not put it back in?

 

[superbenk]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

What about the condenser? You said points, but did you do the rest? For the price of a cap, condenser, plugs & wires I'd just finish the tuneup and make it all new.

 

[Rockslide]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

I cant for the life of me find the rest of what I need. I am having a hell of a time trying to find the right cap. just about everywhere I've looked so far says the part is obsolete but apparently GM used the unstroked and bored version which is the 2.3 in vehicles like the vega (talk about obsolete) and the cavalier and baretta. Can I use the same parts from those. That is where I was able to find the points and rotor and have been trying not to have to go to using auto parts instead of marine grade parts. Does it matter with the particular parts? Does anyone have a lead on where I can get the correct part in a hurry. I am sick of see my boat in my driveway all clean and not so ready to go....

 

[Rockslide]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

I put an inline spark tester and now I have spark to the coil and out of the coil.


What exactly do you mean by you have spark to the coil. There should only be power to the positive side of the coil and spark from the secondary (coil tower) side.
The negative side of the coil is connected in series with the points and condenser, either of which could cause no spark.


I put the tester inline on the no.1 spark plug but have nothing. Whats next? I fell like I'm running out of season!

If you do indeed have spark from the coil tower but not at the spark plugs you either need a new rotor, dist. cap or ignition wires, or E all of the above.

What I meant is that I have 12v to the pos terminal on the coil. I replaced the rotor and points and I have indication of spark coming into the high tension wire. I slid the boot back on the distributor end of the high tension wire and laid the contact across the center opening on the cap. Cranked the engine and no arc. When I used the spark tester I but it before the wire coming out of the coil and got indication. I then put the tester on the end of the wire to eliminate the possibility of a bad wire and I got indication there too. Yet I get no arc?

 

[Maclin]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Sounds like missing or incorrect or broken rotor, or bad/missing spring loaded contact in center of distributor cap, or mismatched cap+rotor.

 

[Rockslide]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Engine is model number MCM140 #A677691

 

[888]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Your motor is a 3.0L and was never used in any vehicles on the road. Was used in forklifts and boats. Heres the cap u need. Order from here or local napa sierra parts#18-5835
http://www.iboats.com/mall/partfind...&gd_poid=111715&gd_row=3&session_id=978271849

 

[Eric 3.7LX Alpha 1]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Here is the link for the complete tune up kit for your engine.
http://www.iboats.com/mall/partfind...&gd_poid=111653&gd_row=3&session_id=036288686

Cap, rotor, points, condenser. The works.......... for a grand total of $26.99 right here at Iboats.

 

[Rockslide]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Your motor is a 3.0L and was never used in any vehicles on the road. Was used in forklifts and boats. Heres the cap u need. Order from here or local napa sierra parts#18-5835
http://www.iboats.com/mall/partfind...&gd_poid=111715&gd_row=3&session_id=978271849

Thanks for the hook up. The 3.0 was built by GM as a 2.3L used in the vega, cavaleir, baretta, and a few mail jeeps. GM took the "OLD DUKE" block and bored and stroked it to the 3.0 sold for forklifts and marine applications. Just FYI.

 

[888]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Thanks for the hook up. The 3.0 was built by GM as a 2.3L used in the vega, cavaleir, baretta, and a few mail jeeps. GM took the "OLD DUKE" block and bored and stroked it to the 3.0 sold for forklifts and marine applications. Just FYI.

GM made a dohc 2.3 in the 90's but nvr used in marine applications. . The "Old Iron Duke" was a 2.5 and is a complete different animal.

 

[Rockslide]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Thanks for all the tips. Got it up and running and now there is a fuel issue. I'll address this in a separate thread. The Old Duke is the block GM modded for Merc. This block and the one in my boat is not a DOHC as this boat is a 1986, which tells me the engine was built before that. From the 70s to the 80s there was only one 2.3L made by GM.

 

[888]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

The Old Duke is the block GM modded for Merc. .

They only did the mod for merc? Wow merc sure is special. Google "Gm Iron Duke 2.5" Note "2.5" Not 2.3. There was a Ford 2.3 used in marine applications,is that what u have? Maybe a ford?

 

[Bondo]

Re: No Spark from Coil on 1986 Mercury 3.0 140 Help!!!

Thanks for all the tips. Got it up and running and now there is a fuel issue. I'll address this in a separate thread. The Old Duke is the block GM modded for Merc. This block and the one in my boat is not a DOHC as this boat is a 1986, which tells me the engine was built before that. From the 70s to the 80s there was only one 2.3L made by GM.

Ayuh,... Yer quite Wrong on that,.... The Iron Duke is the GM corporate/ Pontiac motor used in Cars...

The 2.5l Chevy motor used in boats was used for a short time in Chevy IIs, of the 60s,....

The 3.0l version, which is a bigger Bore motor, is marine/ industrial, 'n Never been in a car...