Hi. Been a while. Hope you are well.
I am working on a 1968 Johnson 65 hp that has been sitting in a boat house for 40 years. I'm working on ignition. not introducing fuel yet. There is no spark on any cylinder.
Found boat side of the harnessing good.
Cleared out the mice and found most of the engine wiring crispy, cracking, exposed and rotted on both the engine harness and components. There was no chance of putting voltage to it.
Replaced the engine harness with new CDI. All matched up perfectly. Fits like a dream.
Found used amplifier and rectifier with good insulation and connectors so I took the chance on being cheap.
Installed the battery. Give it a go and no ignition on any of the four.
I used a CDI ignition manual to help in troubleshooting a 1968 4-cylinder but it was not for the exact engine. It was for a 1968 4-cylinder 100, 115 and 125 hp.
I have 12+ v going to the amplifier from the key switch and when cranking this voltage stays above 9.5 volts. I measure 10.1 v.
Monitoring that red wire feeding the amplifier and striking the points to ground gives no spark and the voltage remains above 9.5 v. I measure 9.9 v.
Attached an induction timing light to the coil output and spark plug wires and got nothing.
DVA attached to the blue wire feeding the coil shows nothing. Based on the "not quite applicable" CDI manual I was expecting 200+v on the blue wire.
Is all this indicating a bad amplifier? The manual never explicitly says "bad amplifier".
Also, what does the rectifier do? It appears to be just for the battery charging circuit. I see it is attached to 12v volts at the battery connection post and 2 yellow wires from the stator but that's it. No connections to anything else. It appears the rectifier does not feed 12 v to any engine electricals. Is this correct?
Thanks,
J
p.s., yes., A service manual has been ordered.
I am working on a 1968 Johnson 65 hp that has been sitting in a boat house for 40 years. I'm working on ignition. not introducing fuel yet. There is no spark on any cylinder.
Found boat side of the harnessing good.
Cleared out the mice and found most of the engine wiring crispy, cracking, exposed and rotted on both the engine harness and components. There was no chance of putting voltage to it.
Replaced the engine harness with new CDI. All matched up perfectly. Fits like a dream.
Found used amplifier and rectifier with good insulation and connectors so I took the chance on being cheap.
Installed the battery. Give it a go and no ignition on any of the four.
I used a CDI ignition manual to help in troubleshooting a 1968 4-cylinder but it was not for the exact engine. It was for a 1968 4-cylinder 100, 115 and 125 hp.
I have 12+ v going to the amplifier from the key switch and when cranking this voltage stays above 9.5 volts. I measure 10.1 v.
Monitoring that red wire feeding the amplifier and striking the points to ground gives no spark and the voltage remains above 9.5 v. I measure 9.9 v.
Attached an induction timing light to the coil output and spark plug wires and got nothing.
DVA attached to the blue wire feeding the coil shows nothing. Based on the "not quite applicable" CDI manual I was expecting 200+v on the blue wire.
Is all this indicating a bad amplifier? The manual never explicitly says "bad amplifier".
Also, what does the rectifier do? It appears to be just for the battery charging circuit. I see it is attached to 12v volts at the battery connection post and 2 yellow wires from the stator but that's it. No connections to anything else. It appears the rectifier does not feed 12 v to any engine electricals. Is this correct?
Thanks,
J
p.s., yes., A service manual has been ordered.
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