1971 Evinrude 60 HP intermittent loss of spark problem

[eddy62]

I have a 1971 60 HP Truimph . It starts well runs great. What happens is every so often the engine just quits. This happens at various RPM . Once it stops it restarts easily immediatly. What we found is its losing spark at that moment( checked in a tank and in the water ). Last year we put a new coil and rectifier on it also a new dist cap and rotor and the carbs were rebuilt.The CDI is about 5 years old . It ran great last year with no problems. This year this has developed. Can someone give me an Idea of where to start and what to test and how. I do have a complete set of manuals but they are a little overwhelming.<br /><br />Thanks for any Help you can give me<br /><br />Ed J

 

[Joe Reeves]

Re: 1971 Evinrude 60 HP intermittent loss of spark problem

Eddy.... Other than loose wires somewhere, I'd suspect a intermitent pulsepack. See the following.<br /><br />(Battery Capacitance Dischage Powerpack Test)<br />Various OMC Engines - 1968 to 1972)<br />(J. Reeves)<br /><br />Purchase a small 12v bulb at your local automotive parts store (the 12v bulb is to look like a flashlight bulb, not a headlight bulb). Solder two wires to that bulb, one to the side of the bulb (ground), and the other to the positive point. <br /><br />Remove the spark plugs. With the key in the on position, make sure that you have 12v going to the pack at the terminal block (purple wire). Now, connect the ground wire from the bulb to any powerhead ground. Connect the wire from the positive point of that bulb to the powerpack wire that is connected to the coil wire on the terminal board (blue wire). <br /><br />Crank the engine and observe that bulb closely (CLOSELY!). If that bulb glows even the slightest bit, the powerpack is okay. It may be a very dim glow... just so it glows! If it doesn't glow, the pack has failed. <br /><br />Keep in mind, that type powerpack (Battery Capacitance Discharge) demands a top notch battery of at least 70 amp hours. Any less will, in time, cause powerpack failure.

 

[eddy62]

Re: 1971 Evinrude 60 HP intermittent loss of spark problem

Thanks Joe<br /> I'll check it out and let you know what I find.<br />Its great to know that someone is able to help with these old motors. All the repair shops I called in Buffalo NY and the outlying areas wont even touch one of these because of the problem with getting parts. It makes it very hard when you know there is still alot of life left in these ole girls.<br /><br />Thanks again<br /><br />Ed J

 

[eddy62]

Re: 1971 Evinrude 60 HP intermittent loss of spark problem

I completed the test as stated above. The CDI checks out fine. I did find thru some further testing that the rectifier I purchased last year was bad I replaced that today. I was wondering if a problem could be with the clipper. I read you can eliminate them . Is this true? If so on this motor are there any wires that need switching or do you just remove it from the terminal? What should the voltage be at the battery with the engine running when tested with a digital meter ?<br /><br />Thanks <br />Ed J