Electronic ignition

[Buttanic]

I am considering converting my 120 Mercruiser to Petronix electronic ignition. Any pros or cons to this. My main concern is reliablity, I can change points, condenser and coil at sea but if the electronics go south I'm dead in the water.<br /><br />Buttanic

 

[1965MT]

Re: Electronic ignition

I changed mine in a 150hp I6. I also kept the old parts for a while just in case. You will like the change.

 

[JasonB]

Re: Electronic ignition

I put a pertroniix in my 302 last year and installed a Pertronix coil. Much better idle and throttle response. Highly recommended. I also keep the points and stuff in a ziplock just in case. I actually keep two sets of points since the original coil was 15k volts and the new one is 40k, a set of points might not last long. Since my wires were 1976 issue, I upgraded them to some Magstar marine wires. Great set-up. Al three were about $180. I used the more expensive Ignitor 2 at $100, the coil was about $40 and I have about $40 in the wires. <br /><br />The vendors here at Iboats likely have what you need. If not, I got mine at vintageperformance.com.

 

[merc 140 pontoon]

Re: Electronic ignition

I like the Pertronix Ignitor conversion on my 1974 Mercruiser 140. I recommend you go with the Ignitor II, so you don't have to worry if you leave the ignition on too long without the engine running. Also, before you invest in this, I strongly recommend that you check the voltage at the coil positive post (CPP). Your 120 most likely have an externally-resisted coil. The external resistance is either in one or two ballast resistors, or more likely in a resistance cable in the wiring harness. My harness resistance cable was deteriorating, and as the engine compartment got hot, the resistance would increase. It got to the point where the CPP voltage would drop below 7.5V, and the Pertronix unit would shut down. Except you don't know that--all you know is the engine quits running. Very frustrating to troubleshoot. I eventually corrected that problem, but a huge problem was that the mechanic who installed the Ignitor didn't follow the directions. They say that, if you have external resistance, then do NOT attach the Ignitor positive lead to the CPP. Instead, attach it to a switchable 12V source. I tapped into the harness before the big plug. So, again, I would check the CPP voltage at various RPMs, and make sure the Ignitor gets wired right.<br /><br />Steve

 

[Boatist]

Re: Electronic ignition

Buttanic<br />I have a 1980 140 hp and in 23 years changed the points one time. Even then only did it because it seemed way over due. I keep the old set plus two new sets and the tools to change on board. To me it is just not a problem that needs fixed. I have installed electronics ingitions on my car and truck. The one on the car failed after about 5 years and I had to walk but I could get out and walk. The one on the truck is fine and also has a switch to switch back to standard at any time.<br /><br />Both units claimed to increase mileage, increase Horsepower, Start faaster. I always check mileage in all my vehicles and the boat for every tank and they made no difference.<br /><br />If you do go for it at least get the one that does not burn up if you leave the key on for two minutes. It can be a long swim.<br /><br />In general I support electonics like the new computer run EFI systems. These actually do make the boat start faster and not need to warm up. They improve Fuel mileage and get better preformance.

 

[Badger99]

Re: Electronic ignition

You can pick up a spare points distributor for $10.00-$25.00 on ebay and have a complete spare in your boat in case you need one. When offshore we allways carry a complete spare ignition because 95% of the time the ignition is why your boat will break down.