1968 Evinrude 100hp Starflite dies

[autoarcheologist]

2 steps forward, one step back.

In the quest to revive our Evinrude outboard we made real progress yesterday. Up until the point when we didn't.

I rigged up a test tank with a 55 gal barrel cut in half, installed the new NGK BUHW-2 plugs, pumped the bulb and hit the key. It fired right up, cleared itself and after a few seconds was running nicely on all 4 cylinders.

I wanted to let it warm up for a few minutes to see if the carbs needed adjusting, so I set it at a fast idle. After a minute or two it just cut out like I had hit the key. Cranking did nothing. Swapped in a second set of plugs, still nothing. Tested for spark and don't have any.

So I'm chasing what I think is an electrical problem. I'm going to try firing it up again and see if it's heat related which I believe would point to the module. But given the shoddy wiring on the 1968 models I'm going to look for any wires that might just be grounding out.

I have a manual with a nice troubleshooting flowchart, so I'm starting there and taking it step by step. But I'm open to ideas or thoughts if anybody else has been here.

Thanks!
Ian

 

[racerone]

You may need a bigger barrel for testing.-------Water must be well above the pump to cool properly and prevent damage to the pump.---------Have you checked the vacuum switch.

 

[autoarcheologist]

Vacuum switch is on the list, thanks!

 

[autoarcheologist]

Well I didn't even get to the vacuum switch. I started at step one, 12V to the module. Which I quickly realized was not there because of the vacuum switch. But once I disconnected the vacuum switch to test at the connector the insulation started failing. And I'm only getting a few millivolts on the primary wire, so it's time for a new wiring harness unfortunately. Better safe than risk a short or fire out on the lake.

 

[autoarcheologist]

OK, I installed a new wiring harness. Only took about an hour, much faster than me trying to rebuild. Way faster.

It didn't include a few wires, like the wire to the vacuum switch, so for now I've just bypassed it to eliminate it from the mix.

I still have no spark unfortunately.

I do have 12V now at the powerpack. My manual had a test for the powerpack. Disconnect the green wire going to the coil, and put a volmeter with a 1000V range in line between the green wire and ground. Then crank. I should see >250V, but I'm not seeing anything.

I'm hoping that the powerpack isn't shot, but before I replace it I have a few other checks to make.

I want to check the blue wires going from the powerpack to the rotor. The manual says they commonly wear through and short out, so that's the first test.

I also see the two yellow wires going to the stator under the flywheel are losing their insulation and might be shorting. I don't know if this would prevent spark, but can't be good. The wires coming out of the rectifier are also fraying so I want to replace the rectifier once I identify the right part,

I'm hoping that one of those issues would prevent spark, or prevent the powerpack from working properly. I can tell that the powerpack was replaced once before based on the manual description.

I'm also planning to use Joe's test in this post: http://forums.iboats.com/forum/engi...rds/313494-68-johnson-100-hp-ignition-project

But first I have to remove the damn flywheel and get at the wires under it.

Questions:

Will a rectifier shorting prevent the pulsepack from firing?

Will the yellow wires going to the stator shorting together prevent spark?

Thanks for any suggestions,

Ian

 

[autoarcheologist]

deleted - duplicate

 

[Willyclay]

I have a manual with a nice troubleshooting flowchart, so I'm starting there and taking it step by step.

Ian, welcome to the first-gen OMC CD ignition system swamp! I have the Johnson version of the same motor and the factory manual has not enabled me to get mine going. Have you found the CDI Electronics trouble-shooting guide at the link below? Maybe that will help you. I am curious where you found a replacement wiring harness since my understanding is they have been NLA for many years and concerned, if it is NOS, it may be from the same source that forum guru Joe Reeves told me produced crap for several years. Sorry I cannot be more help but I will be following your thread closely. Good luck! WC

http://issuu.com/cdielectronics/docs...044661/2001100

 

[autoarcheologist]

WC, I bought a wiring harness made by CDI. It is good quality and fit well. I was concerned about the lack of connectors for the temp sensor and the vacuum switch, but according to the CDI troubleshooting chart they recommend removing those anyway. So that makes sense.

I had the engine running briefly, then it quit. So I'm hoping it's just a case of wiring that has flaked off and shorted together, not the module going bad!

I need to get the damn flywheel off so I can check the wires underneath, that's today's project after picking up a 1 5/16" socket.

 

[Willyclay]

Excellent news about the wiring harness! I think I will cheap it out and rewire it myself. The only gem of wisdom I have gleaned from many sources about this ignition system is that anything other than a fully-charged battery can damage components. Hope that is not the case with yours. Good luck!

 

[autoarcheologist]

Once nice thing about the wiring harness is that it had all the right connectors already installed. If I could figure out how to reuse all of the connectors rewiring would be easier. I suppose you could just order new, generic connectors and not worry about originality.

Back to my testing... I checked the battery voltage again today and it was 12.6V. I'm pretty sure the battery has been in good shape the whole time, this battery is less than a year old, and I threw it on the charger before I started all this.

I checked the rectifier today using Joe's test I found here, post #10- http://forums.iboats.com/forum/engi...outboards/210749-2-yellow-wires-on-new-stator

I saw resistance with the Fluke meter hooked up in both directions, so I assume it's bad. The wires are shot anyway so I need to order one.

I also tried hooking a spark gap tester straight to the coil and cranked, and didn't get a spark. I also tried to measure voltage at the + side of the coil (green wire from powerpack) while cranking, and got something like 0.2V. Not the > 200V I should get.

More testing once I retap the threads on the flywheel and pull it to check wiring underneath.

 

[Willyclay]

More testing once I retap the threads on the flywheel and pull it to check wiring underneath.

The challenges are many on these great old motors. My puller broke before I stripped any threads. Good luck!

 

[autoarcheologist]

I bungled the threads trying to thread a metric bolt into a English hold. Doh! I hope I can clean them up enough for them to hold and not break my puller. I have heard of others hammering a wedge under the flywheel to pop it off, but I don't think we can do it with the distributor under the flywheel. We'll see!

 

[Willyclay]

I picked up a piece of 3/4inch thick steel plate and plan to make my own puller instead of trying to use more cheap Chinese junk from Harbor Freight. I did this very thing many years ago but was unable to find it again after a 300 mile move and a new workshop. I have reservations about the wedge idea. Good luck!

 

[autoarcheologist]

We'll see if mine works. So now that I know my rectifier is bad, I need to figure out if the tests for the power pack will work with it disconnected so I can confirm it's dead before buying a new one.

 

[autoarcheologist]

Alright, a bit more progress today. Ordered a new rectifier and a power pack. And I was able to get the flywheel off. I re-tapped the 5/16 threads, cranked on the puller, gave the flywheel a whack with the hammer and it popped off.

Once it was off I was able to loosen the distributor enough to get the stator off and tape off the two yellow wires so they aren't shorting out. Once I get the rectifier I'll try starting it again, then if no go I'll replace the power pack.

The stator looked good as did the ditributor so hopefully a new power pack will do the trick and we can get this puppy on the water!

 

[Willyclay]

Thanks for the update. Good luck!

 

[autoarcheologist]

Quick update. A new power pack did have the boat running last summer. We had it out twice. On the third time out it started, died and wouldn't restart. When igot it home the powerpaxk failed its test so I sent it back.

I got the power pack back this spring and finally got it installed again last week. And it was DOA. So its going back for a second fix.

Since I am less than impressed with CDIs quality control I am looking into a MSD ignition replacement instead. I have an MSD 6A I am playing with, and I get a spark from it but need to test it with the ignition sensor triggering the spark. And I need to pick a coil.

Anybody else successfully set up an MSD box with the magnetic sensor? I know people have with points.

Fun fun!

 

[autoarcheologist]

This morning I tried the MSD again while cranking. I pulled all the spark plugs so I could watch for spark. When I first tested it by turning on the ignition and connecting the magnetic sensor wires, whichever cylinder the rotor was pointing to would fire.

But as soon as I cranked it it stopped sparking.

I would rather not convert to points, or add a Pertronix ignition, but I'm not sure where else to go at this point.

I plan to measure the gap between the sensor, but am open to ideas.

Thanks,
Ian

 

[Willyclay]

Others have tried the MSD mod with some success. Joe Reeves even got involved. Will search for those threads and post a link if I can find them. Good luck!

 

[autoarcheologist]

Thanks for the encouragement. Unfortunately it seems that everybody who has made it work has used a points trigger, and so far I understand why.

I'm not quite ready to convert to points.