Electronic Ignition Conversion

Reming870

Petty Officer 2nd Class
Joined
Jul 15, 2010
Messages
191
Any recommendations?

There seems to be quite a few different types, price levels and manufacturers for these kits.
 

kilowatts

Petty Officer 1st Class
Joined
Apr 3, 2009
Messages
299
Re: Electronic Ignition Conversion

Hi Guys:

I'm on the fifth Mercruiser 165 inline 6 rebuild in 2 years. I've put Pertronix electronic conversions in each engine with zero problems. I've looked at the Hot Spark and they seem to be the equal and much cheaper than Pertronix, but that's only an opinion.

kilowatts
 

jcupo6

Chief Petty Officer
Joined
Jul 13, 2009
Messages
512
Re: Electronic Ignition Conversion

Hi Guys:

I'm on the fifth Mercruiser 165 inline 6 rebuild in 2 years. I've put Pertronix electronic conversions in each engine with zero problems. I've looked at the Hot Spark and they seem to be the equal and much cheaper than Pertronix, but that's only an opinion.

kilowatts

I'm about to install Pertronix in my Merc 120hp. I don't have an experience with thses, but have done a ton of research and it seems pretty much everyone is happy with their results.
 

essveedub

Cadet
Joined
Jul 6, 2010
Messages
9
Re: Electronic Ignition Conversion

I have the pertronix unit in my '76 MCM 140. Install was easy - hardest part was that I had to notch the dist. cap for the wiring. The engine seems to start easier and run a little smoother, but that's most likely from not knowing how to set up the old points and condensor system. The concensus here seems to be that you will get no performance gains from electronic ignition conversion over points with properly set gap and dwell.

I'm sure other conversion kit makers will give you similar results. If you're thinking about a pertronix unit, check out this site: http://www.vintageperformance.com/retrorockets/marine.htm for the type for your motor.
 

PiratePast40

Lieutenant Commander
Joined
Mar 21, 2009
Messages
1,734
Re: Electronic Ignition Conversion

I'm using the Hot Spark kit and their resistance coil wiith no problems.
 

Reming870

Petty Officer 2nd Class
Joined
Jul 15, 2010
Messages
191
Re: Electronic Ignition Conversion

I have the pertronix unit in my '76 MCM 140. Install was easy - hardest part was that I had to notch the dist. cap for the wiring. The engine seems to start easier and run a little smoother, but that's most likely from not knowing how to set up the old points and condensor system. The concensus here seems to be that you will get no performance gains from electronic ignition conversion over points with properly set gap and dwell.

I'm sure other conversion kit makers will give you similar results. If you're thinking about a pertronix unit, check out this site: http://www.vintageperformance.com/retrorockets/marine.htm for the type for your motor.

Just ordered through this site. They are cheaper than Pertronix direct and very helpful with email questions. Thanks for the link!!! Hopefully this will work out well. I'll repost after the install for anyone interested in results.
 

sethjon

Senior Chief Petty Officer
Joined
Jun 8, 2010
Messages
692
Re: Electronic Ignition Conversion

Why are you doing a conversion? Points are great when adjusted properly.
 

haulnazz15

Captain
Joined
Mar 9, 2009
Messages
3,720
Re: Electronic Ignition Conversion

Why are you doing a conversion? Points are great when adjusted properly.

Well points are great when they are adjusted and new, but as the engine turns, it wears down the points and causes a loss in ignition performance due to the nature of the design. This takes time, but you can pretty much state that performance will not be as great in one or two years as it was when the points/gap/dwell was new. Electronic ignition allows for optimum performance indefinitely as there are no points to wear down.

The main upside to points-style ignition is that even when they start to go out, you can usually get back into shore or replace the quickly on the water with a spare set of points. Electronic ignitions tend to go out with little/no notice and aren't likely to let you get back to shore. But like points, a spare electronic unit can be kept on board and swapped out with relative ease.
 

essveedub

Cadet
Joined
Jul 6, 2010
Messages
9
Re: Electronic Ignition Conversion

They are cheaper than Pertronix direct and very helpful with email questions. Thanks for the link!!!

Yeah no prob - I paid less for a pertronix ignitor kit and a coil thru that site than I did for the ignitor kit alone at a marine dealer here. The shipping was fairly quick - considering it was cross-border.

On that note - let me point out that the reason I had to buy a new one was because I wrecked the original ignitor kit. I had not properly adjusted the gap between the sensor and the magnet wheel, which resulted in the wheel rubbing on the sensor, and killed it! Took off the cap and found a bunch of plastic shavings. Luckily I was at the dock when the boat just quit.

The kit I just put in has a little clear plastic strip and instructions used to set the gap between the magnet wheel and the sensor. Make sure to use it! I made sure not to repeat my costly dumb**s mistake again.

Oh yeah - I've heard that these kits don't like to have the igniton switch on without the engine running for more than 30 seconds, or you could damage the sensor... So basically with either points or electronic ignition you don't want to leave the key on.

Hope this helps! Good luck and let us know how the install goes.
 

Reming870

Petty Officer 2nd Class
Joined
Jul 15, 2010
Messages
191
Re: Electronic Ignition Conversion

Got it done last night. REAL EASY. Pertronix has a new plate for the distributor so its as easy as taking the points plate off, putting the new sensor plate on, gap the spacer, connect the wires and go.

Also changed the coil as well to the recommended Pertronix one.

One side note: The new coil can take 12 volt to it. I am getting 8.5 volts. I am making the assumption there is a resistor somewhere OR the ignition wire is a resistance wire??? Any ideas???

Fired right up. Getting it in the water tonight and will see if my problems will go away with this change.

Did I mention I ordered it on Wednesday AM and it was at my house on Thursday afternoon. Thanks for the link to Vintage Performance eesveedub.
 

jimbo3123

Seaman Apprentice
Joined
May 17, 2009
Messages
35
Re: Electronic Ignition Conversion

Got it done last night. REAL EASY. Pertronix has a new plate for the distributor so its as easy as taking the points plate off, putting the new sensor plate on, gap the spacer, connect the wires and go.

Also changed the coil as well to the recommended Pertronix one.

One side note: The new coil can take 12 volt to it. I am getting 8.5 volts. I am making the assumption there is a resistor somewhere OR the ignition wire is a resistance wire??? Any ideas???

Fired right up. Getting it in the water tonight and will see if my problems will go away with this change.

Did I mention I ordered it on Wednesday AM and it was at my house on Thursday afternoon. Thanks for the link to Vintage Performance eesveedub.

If you are getting 8.5v at the coil, the resistor is still installed. You must remove that resistor and connect the switched +12v directly to the positive side of the coil, or the electronic ignition will die very quickly (I had one last a few hours).

Another advantage of an advanced electronic ignition such as the Pertronics Ignitor 2 is that it will sense a "Key left on" condition and shut down power to the coil.
If you leave the key on with the engine stopped with a points setup, and the points are closed, the coil is left energized and will get very hot and eventually burn out.
 

Reming870

Petty Officer 2nd Class
Joined
Jul 15, 2010
Messages
191
Re: Electronic Ignition Conversion

I cannot find a resistor.

Where is it?

Is it possible the ignition wire is a resistance wire?
 

essveedub

Cadet
Joined
Jul 6, 2010
Messages
9
Re: Electronic Ignition Conversion

It is a resistor wire. If you bought the 3 ohm coil, then you should remove it. and replace with a regular piece of wire. This is assuming you're doing a 4 cyl 140hp engine?

I unwrapped my harness from the coil back far enough to expose it. It was longer than the other wiring and therefore doubled back in the sheath. The resistor wire joined the tan wire from the starter solenoid at the coil "+" post connector, and was soldered at the other end to a white wire from the harness plug. I simply cut it out and soldered in a normal wire (can't remember the gauge, but was similar to the other harness wires).

I left the tan wire from the starter solenoid attached to the coil as well, although may not need it. I believe its supposed to bypass the old resistor wire and supply +12 volts to the coil for start up only.

If you've got a copy of the service manuals youi can refer to the wiring diagram in the Service Manual #2 - page 3E-10 for the 120,140, and 165 Mercs.

I know - quick shipping and there was no shipping charges - even to Canada!
 

jimbo3123

Seaman Apprentice
Joined
May 17, 2009
Messages
35
Re: Electronic Ignition Conversion

I cannot find a resistor.

Where is it?

Is it possible the ignition wire is a resistance wire?

I couldn't find mine either. It's probably safe to say that it's buried out of reach somewhere, so I just jumpered around it and installed a switched + 12v wire to the + side of the coil (leaving the resistor installed as well). The added bonus is that I can switch back to points if needed by just swapping the parts and removing the jumper wire to the coil.

If you're reading 8.5V at the coil with the key on, the resistor is definitely there, even if you can't find it.
 

Reming870

Petty Officer 2nd Class
Joined
Jul 15, 2010
Messages
191
Re: Electronic Ignition Conversion

What is the purpose of the second wire on the coil going to the starter solenoid?

If I redo this resistance wire it will have 12 volt instead of 8.5 volt and I want to make sure it doesn't destroy anything.
 

essveedub

Cadet
Joined
Jul 6, 2010
Messages
9
Re: Electronic Ignition Conversion

The purpose of the resistor bypass wire is to deliver full 12 volts to the coil at start up. This gives the coil maximum energy for a hotter spark at startup = easier starting. Once running the resistor wire takes over, and reduces the voltage to the coil, as the original spec coil (1.5 - 1.8 ohms internal resistance). Those coils will burn out if run at full 12 volts for a long period. But can handle it for starting purposes

The coil I bought with the Ignitor kit (Flamethrower 40611 - 3.0 ohm - epoxy filled) can run with full 12 volts due to it's higher internal resistance, and doesn't require the resistor wire. The instructions that came with the coil said to connect it without the resistor wire for my application.

If you were to keep your original coil, they recommend that you leave the resistor wire on the coil, and connect the red Ignitor lead to a switched full 12 volt lead. However, I ran the my previous Ignitor kit with original coil, and the Ignitor worked fine with the reduced voltage.
 

Reming870

Petty Officer 2nd Class
Joined
Jul 15, 2010
Messages
191
Re: Electronic Ignition Conversion

My problems appear to be solved. I ran a new wire to the 12 volt connection where the resistor wire is connected in the harness. If anyone is ever looking for this it is very close to the harness connection point that is bolted in. The resistor wire goes down the harness towards the alternator and then doubles back to the coil. I left it in place (Just in case) and ran a new wire. Solved my "sputtering" problem at WOT.

Now, onto the prop problem. A post in another direction.

Thanks for the help everyone!!!
 
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