1990 70HP Johnson Ignition Problems

ChaseK3

Cadet
Joined
Apr 29, 2007
Messages
8
As you can tell by the title I have a 70hp Johnson. I have only had the boat around 6 months. When I got it, I was having some problems. I took it to a shop and found out the power pack was bad. I replaced the powerpack and the boat was running great. I was coming in from the lake at WOT and the motor died. I pulled the cowl and saw that the throttle linkage rubbed through the white wire coming from the timer base. I repaired it by using two bullet connectors, but it didn't fix the problem. The motor started but would die after it warmed up, and wouldn't restart. I started trouble shooting according to my Seloc manual. The power pack wasn't producing like it was supposed to. I called CDI and they replaced it free (warranty). That didn't fix the problem. I tested the stator, and it was out of spec. It wasn't producing the voltage it was supposed to, and the Ohms were not in spec. I replaced it yesterday. That didn't fix the problem either. I went back to my trouble shooting chart. Now the timer base isn't producing the 0.3 volts that it is supposed to deliver, but the resistance is still okay according to the charts. I am not getting any spark on #1 cylinder, I am getting erratic spark on #2, and I'm getting good spark on #3. Does anyone have any suggestions? Also, the stator I got from CDI has two wires coming off of it that go the rectifier. The original stator had a Y and a Y/G. The new wires are both Y. Does it matter which wires they attach to at the terminal board? They both deliver the same votage. One more thing. The yellow wires coming off of my rectiver look discolored at the terminal board. They have a black color on the insulation. Is this a problem? I know this is a long post, but I would appreciate any help you guys can offer.
 

CHRIS-CRAFT

Recruit
Joined
Jul 4, 2007
Messages
3
Re: 1990 70HP Johnson Ignition Problems

Try Disconnecting The Rectifier And See If Your Problem Clears Up.
You Can Run The Motor With It Disconnected, With No Problem.
A Bad Rectifier Will Make A Motor Do Stange Things.
 

ChaseK3

Cadet
Joined
Apr 29, 2007
Messages
8
Re: 1990 70HP Johnson Ignition Problems

I tried unhooking the rectifier. It still won't start. I re-checked the specs on the timer base and it wasn't in spec. I ordered a new one, as well as a new rectifier. I also checked the kill and key switches. They were both fine.
 
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