Motor- 2004 Johnson 150 Carbed V6 60deg
model J150PXSRB
Bought the motor off a friend, tree fell on the boat crushing the console and the cowling. motor was running rough. Turns out it was a bad power pack as QuickStart was not disengaging, looked like the top of the powerpack was cracked. Now, with a brand new powerpack, about 50-60% of the time the motor idles just fine. The rest of the time it’ll start and sit around 1000rpms for a few seconds then slowly start to climb up to 1500-1800rpms. It sounds like it’s the timing that’s advancing the rpms, as the butterflies are all closed against the throats and all throttle linkages are at their stops. I know anything’s possible, but does this sound like the powerpack being the culprit again, did I get a bad one from BRP? If so, would it be worth maybe trying out one of the aftermarket CDI powerpacks? If not, could it maybe be a bad stator supplying inconsistent power to the powerpack? The optical sensor was replaced with the power pack but maybe that could be what’s faulty?
Ive been trying to track when it runs fine and when it doesn’t. It seems to be completely random. Was thinking maybe it was a crank case seal or head gasket giving a vacuum leak, leaning the mixture, cause the RPMs to run away.
My mechanics thinks it’s a powerpack, since grounding out QuickStart doesn’t seem to have any effect on the RPMs. I figured QuickStart shouldn’t be engaged anyway Above 1150/1200rpm so there wouldn’t be any change if you grounded it out at 1800rpm. But then again, if the powerpack is bad, t wouldn’t be able to tell it to turn off past that 1150/1200 point anyway...
Thoughts?
model J150PXSRB
Bought the motor off a friend, tree fell on the boat crushing the console and the cowling. motor was running rough. Turns out it was a bad power pack as QuickStart was not disengaging, looked like the top of the powerpack was cracked. Now, with a brand new powerpack, about 50-60% of the time the motor idles just fine. The rest of the time it’ll start and sit around 1000rpms for a few seconds then slowly start to climb up to 1500-1800rpms. It sounds like it’s the timing that’s advancing the rpms, as the butterflies are all closed against the throats and all throttle linkages are at their stops. I know anything’s possible, but does this sound like the powerpack being the culprit again, did I get a bad one from BRP? If so, would it be worth maybe trying out one of the aftermarket CDI powerpacks? If not, could it maybe be a bad stator supplying inconsistent power to the powerpack? The optical sensor was replaced with the power pack but maybe that could be what’s faulty?
Ive been trying to track when it runs fine and when it doesn’t. It seems to be completely random. Was thinking maybe it was a crank case seal or head gasket giving a vacuum leak, leaning the mixture, cause the RPMs to run away.
My mechanics thinks it’s a powerpack, since grounding out QuickStart doesn’t seem to have any effect on the RPMs. I figured QuickStart shouldn’t be engaged anyway Above 1150/1200rpm so there wouldn’t be any change if you grounded it out at 1800rpm. But then again, if the powerpack is bad, t wouldn’t be able to tell it to turn off past that 1150/1200 point anyway...
Thoughts?
Last edited: