1985 Johnson v4 90hp.
Heard a rattle today taking off from the dock. Sounded "tinny" like metal on metal (like the flywheel and flywheel nut). Got slightly louder with increasing RPM but otherwise ran fine. Drove about 3 miles. Shut motor off and sat an hour.
Started motor and rattle was louder immediately. When trying to accelerate there was power loss. I put throttle down more but RPM didn't increase as it should have. Nose of boat was high in the air and could only go about 10 mph during this. After a minute or two the RPM increased (surged?) to almost 4k, where it should be in that throttle position. I reduced throttle and motor behaved normal (except for rattle, but a little less loud) back to dock.
When I got it home I got out the breaker bar and tried to torque the flywheel nut more, but don't think I moved it. I do NOT think it is at the 100 ft lbs spec, though but I don't want to put an impact on it.
Then I put it on the hose. NO RATTLE. Volts off the battery were 13 at idle and 14 under load. Note: I recently replaced the water cooled regulator rectifier with snow OEM one (thus flywheel recently being off).
I tested the stator. Without the motor running, infinite ohms yellow to ground, and yellow to yellow wires was 0 to 0.1 ohms. Digital volt meter beeped showing continuity between yellow wires. These are the same readings as a month ago when diagnosing the problem that ked to replacing the
However, I saw in one of the manuals I have that spec is 0.7 +/- 0.05 ohms. It isn't an OEM manual so not sure the accuracy. Is 0 to 0.1 ohms too low?
Tested compression: 130, 124, 120, 124
I also just found out I was running the wrong plugs. I was running resistor plugs, so I just changed them tonight.
Edit: just tested stator ohms again and now get around 1.6. Still beeps for continuity.
Any thoughts?
Heard a rattle today taking off from the dock. Sounded "tinny" like metal on metal (like the flywheel and flywheel nut). Got slightly louder with increasing RPM but otherwise ran fine. Drove about 3 miles. Shut motor off and sat an hour.
Started motor and rattle was louder immediately. When trying to accelerate there was power loss. I put throttle down more but RPM didn't increase as it should have. Nose of boat was high in the air and could only go about 10 mph during this. After a minute or two the RPM increased (surged?) to almost 4k, where it should be in that throttle position. I reduced throttle and motor behaved normal (except for rattle, but a little less loud) back to dock.
When I got it home I got out the breaker bar and tried to torque the flywheel nut more, but don't think I moved it. I do NOT think it is at the 100 ft lbs spec, though but I don't want to put an impact on it.
Then I put it on the hose. NO RATTLE. Volts off the battery were 13 at idle and 14 under load. Note: I recently replaced the water cooled regulator rectifier with snow OEM one (thus flywheel recently being off).
I tested the stator. Without the motor running, infinite ohms yellow to ground, and yellow to yellow wires was 0 to 0.1 ohms. Digital volt meter beeped showing continuity between yellow wires. These are the same readings as a month ago when diagnosing the problem that ked to replacing the
However, I saw in one of the manuals I have that spec is 0.7 +/- 0.05 ohms. It isn't an OEM manual so not sure the accuracy. Is 0 to 0.1 ohms too low?
Tested compression: 130, 124, 120, 124
I also just found out I was running the wrong plugs. I was running resistor plugs, so I just changed them tonight.
Edit: just tested stator ohms again and now get around 1.6. Still beeps for continuity.
Any thoughts?
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