1974 Evinrude No Spark

First off i just want to thank all of you for these forums, they have helped me immensly! I have a 1974 Evinrude 50hp model #50473M. I have the CDI troubleshooting guide and have done the first two "easy steps". Here is the thing, the boat will run one day, and not the next. I ran it for 15 minutes at the house and it did great, drove to the lake, backed it down the dock and it wont start. Pull it out, and after a little work it starts. Needless to say i did that two more times and i gave up. I drove home "this was monday" I have tinkered with it since and cant get it to start. This morning i walk out of the house and it fire's right up, tonight no dice. I know that i am getting fuel, and that is not the problem. I Have pulled the plugs and i am not getting spark from either coil. I have also pulled the two yellow wires and no spark, i have also pulled the black/yellow wire and no spark. It has me a little baffled that it will start one day and not the next. Any helpful hints will be greatly appreciated Thankyou in advanced!!!!

Re: 1974 Evinrude No Spark

^^Bump^^ Surely someone has heard of this problem and can help me out? I have done a few tests from the manual and troubleshooting guide, and I think its the power pack, anyone have any ideas??

Re: 1974 Evinrude No Spark

Wy didn't you finish the troubleshooting of the engine?
There are several componets in you ignition system that can cause your problems.
I have found in the past that if all the checks are OK, most of the time it's the power pack causing intermitent problems.

Re: 1974 Evinrude No Spark

I had the same problem when I got my used boat. Changed my power pack and all has been well.

Re: 1974 Evinrude No Spark

I did finish troubleshooting the electrical system. Here is the thing all continuity checked out good and Volts were extremely high when i tested the brown wire to engine ground I think they were 1000. The next test i did was the black white to white black i received a very lov voltage approximately .1. Which wires are the timer based wires that i need to unhook and test? Any thoughts or comments are greatly appreciated!!!

Re: 1974 Evinrude No Spark

I too had this sor of issue. But since I changed my Power Pack it starts every time (knock on wood). Also check wiring harness' if it has one. a loose connection, bent pin, or crushed wire could cause intermittent problems like that.

Re: 1974 Evinrude No Spark

What kind of a meter are you checking these out puts with ?

Re: 1974 Evinrude No Spark

From what i can understand, the signs are leading to the pack being bad. Im no stranger to turning a wrench but i havent used a multimeter much at all. Boobie I am using a Performance tool multimieter. It says that it is guaranteed to 2%. It is this one.
http://www.amazon.com/Performance-W...4604/ref=sr_1_1?ie=UTF8&qid=1336452310&sr=8-1

Re: 1974 Evinrude No Spark

Can you use a DVA adapter with that meter 'cause that's what you'll need to check out the system ?

Re: 1974 Evinrude No Spark

Thanks a bunch boobie!!! That could be why i have been having issues testing!!

Re: 1974 Evinrude No Spark

Just my two cents worth but could be a bad ignition switch. I had same problem with my 74 70hp kill switch part of ignition was ingaging intirmently to test disconect the the black /yellow wire from ignition switch M post cover in electrical tape and try starting WARNING MOTER WILL NOT TURN OFF WITH KEY I choked mine to turn of or you may have to diconect battery hope this helps but an ignition switch is much cheaper then power pack