danwheeler
Recruit
- Joined
- Aug 12, 2017
- Messages
- 1
Hello,
I've got a 1988 SeaRay with a Mercury 100 outboard that has been running great but suddenly developed some problems. We had it out in the morning and it was running great then suddenly started surging and dropping RPMs while on plane. Eventually things went downhill and just wasn't running right.
The night before included these changes:
- Filled 2-cycle oil
- Installed new accelerator pump (had been running great with it removed and the in/out plugged)
- Filled gas tank
First thing we did was remove the accelerator pump and go back to bypass since that had been working great. Problem was still there so we put it back in. Today we spent hours learning about this motor and checking spark on each of the plugs trying to get our heads around the rough running. For a while we weren't getting spark on cyl. 1 but that problem disappeared on its own. We spent about 5 hours trying to figure out why we suddenly lost ALL spark only to find out that the kill switch was the cause because we had the motor in a garbage can full of water (no earmuffs) and had raised it to the point where the kill switch was kicking in.
it's been a long day... We have all 4 plugs wires firing, so we think both stators are good?
we've got it back to the point where it will idle for a while but does run rough and will eventually die or backfire. We've been using the meter to check resistance on the stator and trigger wires. We are having some trouble finding the right specs and testing procedure for this motor but if we're getting spark to all 4, does it matter? Our red/blue and red/wh/blu/wh resistance measurements seem to be off from the specs we have but we still need to confirm that. Our purple, brown, white and black stator wires read resistance as expected.
We've taken the flywheel off and learned that there are two stators... one to generator power and one to trigger ignition. Question - if the power stator were bad, could it cause our problem if we have a fully charged battery? Does the ignition system run off battery power or is it powered solely by the stator?
As we have fuel air and spark, and it does run, my best guesses are fuel pressure, flooding or timing. I've removed the choke solenoid and plugged both ends thinking maybe the choke solenoid is passing fuel through causing flooding... complete wild guess though.
just learned this motor may be a "2 + 2" system which would explain a lot of the weirdness we didn't understand like removing plug wires have no effect or spraying starting fluid into the carbs having a different effect on the top and bottom carbs.
Any suggestions are helpful - we're in a jam here as it's our annual family vacation and the kids want to go tubing!
thanks,
Dan
I've got a 1988 SeaRay with a Mercury 100 outboard that has been running great but suddenly developed some problems. We had it out in the morning and it was running great then suddenly started surging and dropping RPMs while on plane. Eventually things went downhill and just wasn't running right.
The night before included these changes:
- Filled 2-cycle oil
- Installed new accelerator pump (had been running great with it removed and the in/out plugged)
- Filled gas tank
First thing we did was remove the accelerator pump and go back to bypass since that had been working great. Problem was still there so we put it back in. Today we spent hours learning about this motor and checking spark on each of the plugs trying to get our heads around the rough running. For a while we weren't getting spark on cyl. 1 but that problem disappeared on its own. We spent about 5 hours trying to figure out why we suddenly lost ALL spark only to find out that the kill switch was the cause because we had the motor in a garbage can full of water (no earmuffs) and had raised it to the point where the kill switch was kicking in.
it's been a long day... We have all 4 plugs wires firing, so we think both stators are good?
we've got it back to the point where it will idle for a while but does run rough and will eventually die or backfire. We've been using the meter to check resistance on the stator and trigger wires. We are having some trouble finding the right specs and testing procedure for this motor but if we're getting spark to all 4, does it matter? Our red/blue and red/wh/blu/wh resistance measurements seem to be off from the specs we have but we still need to confirm that. Our purple, brown, white and black stator wires read resistance as expected.
We've taken the flywheel off and learned that there are two stators... one to generator power and one to trigger ignition. Question - if the power stator were bad, could it cause our problem if we have a fully charged battery? Does the ignition system run off battery power or is it powered solely by the stator?
As we have fuel air and spark, and it does run, my best guesses are fuel pressure, flooding or timing. I've removed the choke solenoid and plugged both ends thinking maybe the choke solenoid is passing fuel through causing flooding... complete wild guess though.
just learned this motor may be a "2 + 2" system which would explain a lot of the weirdness we didn't understand like removing plug wires have no effect or spraying starting fluid into the carbs having a different effect on the top and bottom carbs.
Any suggestions are helpful - we're in a jam here as it's our annual family vacation and the kids want to go tubing!
thanks,
Dan