I've got a 1970 V4 85 hp Johnson. It's really clean, better than average condition, compression is 125 psi all around. The motor is throwing a lot of problems at me, ignition and gear shifting.
#1. Ignition. No spark. At all. Old style distributor under flywheel, with amplifier and coil. Amplifier is getting it's 12 volt supply. No voltage is sending to coil, from amplifier. I checked with an oscilloscope. I suspect it's the amplifier but at over $300 I would like to be sure. Any other diagnostic tests?
#2. Hydro-electric shift. Symptom is no neutral. Neutral shift position renders forward gear, as does forward shift position. Reverse shift position renders....reverse. Voltage on two solenoid shift wires is correct. Select neutral, green wire carries 12v. Select reverse, green and blue wires @ 12v. Select forward, no volt either wire. All testing done dry, plugs out, crank motor over with starter.
Is it possible that my observed "forward gear in neutral" is the prop shaft sympathetically spinning but not engaged? It sure doesn't look like it. That prop is going fast. How could I gently load it, without hurting myself or the lower unit? Failing that bit of wishful thinking, any ideas as to the culprit? I am really reluctant to open the hydro-electric up.
Finally, given that both these problems are with systems that were very short lived by OMC standards, should the motor just be retired?
Thanks.
#1. Ignition. No spark. At all. Old style distributor under flywheel, with amplifier and coil. Amplifier is getting it's 12 volt supply. No voltage is sending to coil, from amplifier. I checked with an oscilloscope. I suspect it's the amplifier but at over $300 I would like to be sure. Any other diagnostic tests?
#2. Hydro-electric shift. Symptom is no neutral. Neutral shift position renders forward gear, as does forward shift position. Reverse shift position renders....reverse. Voltage on two solenoid shift wires is correct. Select neutral, green wire carries 12v. Select reverse, green and blue wires @ 12v. Select forward, no volt either wire. All testing done dry, plugs out, crank motor over with starter.
Is it possible that my observed "forward gear in neutral" is the prop shaft sympathetically spinning but not engaged? It sure doesn't look like it. That prop is going fast. How could I gently load it, without hurting myself or the lower unit? Failing that bit of wishful thinking, any ideas as to the culprit? I am really reluctant to open the hydro-electric up.
Finally, given that both these problems are with systems that were very short lived by OMC standards, should the motor just be retired?
Thanks.