New and lost. Can’t get above 3000 rpm

[aw5716]

Ok I’m new here and could use some help. This site seems awesome. Serial # OC162166. Mercury 1989 80 hp. I’m having a hard time getting the boat above 3000rpms. Sometimes it will. Sometimes it won’t. I don’t know much about it all. Still learning. I need to know how and what to trouble shoot. Trimming up and down seems like it helps sometimes. I get up to 5500rpm with fast idle lever trimmed up with exhaust out of the water, trimmed down only get it to 4000. I mess with the idler set screw on the 3 carbs and it seems to help. It usually will run awful on these cold mornings for about the first hour then open up and run great for the rest of the day. Seems to be getting worse, dying at wot while trimming up. Having problems even after being warmed up. When it starts running good and I’m idling at a pier it seems to have a lean sneeze and I’ve even seen some fine gas spray on the water at this time
Thanks

[straffordengineer]

We need a serial number to assist you.

[aw5716]

I posted it in the original post but here it is again Serial #OC162166

[aw5716]

Anyone?

[rickdb1]

I'd be cleaning/rebuilding and syncing the carbs. Also check the reeds when you have the carbs off. Running lean is never a good thing on a 2 stroke..

[aw5716]

Thanks Rick I’ll do that.

[Lowerider58]

I need to know how and what to trouble shoot. Trimming up and down seems like it helps sometimes. I get up to 5500rpm with fast idle lever trimmed up with exhaust out of the water, trimmed down only get it to 4000

if you meant your getting to 5500. RPM in neutral you can't keep doing that. You will throw a rod through the side of the block. You should never rev an engine past a fast idle without a load.

[06 SB]

Have you replaced the fuel lines? If not then do it first.

[aw5716]

Yes that’s what I meant, I get to 5500 rpm with fast idle lever. I’ll stop doing it. Don’t want to throw a rod. It was the only way I could get the engine to operate normal. Or open up if you will. It had a little metal fuel filter that was on backwards. I have changed some of the fuel lines when I changed the fuel filter to the correct one. I’ll make sure to change all fuel lines.

[SilverFox579]

Has this engine ever run correctly in the time you've owned it?

[aw5716]

Yes it has run great since I bought it in September. Only recently did this problem start. I think it had been sitting up a while. Knowing what I know now I would have done some things different before running it. I just bought the boat and started fishing.

[JOE54]

check fuel filter for tell tale signs of fuel line and or system problems any trash,need to find source

[aw5716]

Thanks! I’ll check that as well.

[aw5716]

Update- Set spark tester to 3/8 inch gap. Performed a spark test and had no spark on one coil. Moved coils around and now have spark on all coils. Seems to be just corrosion on brass nuts on coil leads.

Ill just keep commenting on my own post! Ha ha. If no one has anything to add, maybe someone can learn from this. The next morning I did the same spark test. Again no spark on bottom coil. So I moved wires around on switchbox. Problem followed wires. Coils are all good. Switchbox is bad. Have a new one ordered. A helpful more experienced guy from another site has helped me do the troubleshooting. I’ll keep updating til the bitter end!

[aw5716]

Switchbox didn’t fix it. Little to no spark now. My manual gives me ohm readings for stator and trigger and I think they’re both bad. If that’s possible? Red and blue stator leads read 3.4. They’re supposed to read 3.6-4.2. Between red stator lead and powerhead ground the reading is 111. Manual says 90-140 is good. I’ve got good numbers one way and bad numbers testing the other way. Is it bad?
Trigger readings- Brown and White/black trigger leads 6, white and white/black 12, violet and white/black 8. Manual says it should read between 11-14. Are all 3 colors supposed to read between 11-14 or just one?

[JOE54]

each test on trigger 11-14 likely bad trigger black white trigger bad about breaking down internally

[aw5716]

New stator and new trigger installed. So far so good!!

[JOE54]

good deal