Posted by renoduckman on 04/01/06 - 7:53 AM
#1
I have a 1988 Mercury 80 hp 3 cylinder. I'm trying to troubleshoot some electrical problems. I have an intermittent miss on the lower cylinder. I recently changed the rectifier because it wasn't charging. That seemed to help the charging problem but not the miss.
I'm an electrician and have a manual but I'm not a guru of outboards. I seem to be getting 16 or more volts and that seems high to me! There is no regulator on these motors I guess and that seems odd. If any one has any idea what voltage these motors normally put out or any ideas I will appreciate it.
Thanks, Joe
Edited by Tom W Clark on 04/04/06 - 8:42 AM
Posted by danedg on 04/04/06 - 12:03 PM
#2
Dear Reno,
I've got pretty much the same motor. When I first got it (used), it had an intermittent miss. Taking it someone who KNOWS, I ended up replacing the "trigger switch".
{Don't ask me...I couldn't explain it in detail to you}. It is some sort of a harness that helps synchro the firing order on those motors. My motor has run like a top ever since. It was well worth the $300 for parts and service.
I'm not saying that is your exact problem...but my mechanic (bless his little fuzzy head) pinpointed it immediately.
Which brings me to my second point.
I'm a good mechanic, a decent electrician, a cabinetmaker by trade, all in all a pretty handy fellow...but I killed TWO pefectly good used outboards by mucking around with 'em, before I learned that I don't know shinola about outboards!
A few people do...most people don't!
Find a good mechanic in your area, and buy him a drink. He's a lot cheaper date than a new powerplant...
Check your battery connections, and all connections to and from that rectifier CAREFULLY! I had a tiny break in a 16g. wire that fried a battery, a tachometer and the old rectifier!
I can change the propellor, check the oil, change the plugs...and that's it! Everything else goes to 'Ol Bill...he prefers Jim Beam....
Posted by danedg on 04/04/06 - 12:13 PM
#3
Reno,
You're right there is no regulator. Merc used a solid state rectifier to govern the voltage flow from the magneto. Around 14 volts. You've got the book. They are relatively cheap and easy to replace. Your motor is old enough to get a new one...just because.
Posted by renoduckman on 04/08/06 - 6:37 PM
#4
I appreciate the advice. Getting some advice and doing some test with a expensive Fluke, it appears the swtich box is bad. I got a good deal on the montuck from some freinds. Yes, id like to repower it but i have visions of a larger whaler and i dont want to sell my kidney to buy a new motor now? This one seems to run strong when the miss is gone. Thanks Joe