VacationusInterruptus! Tracker75 idles/revs fine but then bogs when under load...

[FiveO]

I have a 2001 Merury Tracker 75 ELPTO outboard on our family pontoon boat. It was not properly winterized and sat with about 25ish gallons in the 30 gallon tank.

Well yesterday it started great in the yard. Idled a tad rough but evened out. Reved fine. Dropped her in the water and took off, ran great for a few minutes but then just lost all of it's "oomph." Maybe 3500-4000 RPM at full throttle with occasional surging.

Figuring the gas was bad I said the heck with it and drained and disposed of the old gas (which looked fine to me and flowed out of the gas line well) and put 10 gallons of fresh in it along with a product the guy at West recommended, "Quicksilver Fuel System Treatment and Stabilizer."

The motor cranked easily and would rev well. Feeling optimistic I dropped her back in only to have the exact same problem. This time it was idling a bit rougher and dying at times when put in gear and not going over 3000 rpm with small surges... Again, in neutral it woud rev normally.

So we have company coming later in the week and I'm at a loss...

Ideas, input Gentlemen?

It is greatly appreciated.

 

[CharlieB]

Re: VacationusInterruptus! Tracker75 idles/revs fine but then bogs when under load...

You need to troubleshoot to determine the problem.

Compression test

Spark test

If both check out fine then you can be sure the problem is a dirty carb or failing fuel pump or hoses.

Unfortunately without testing you have no idea, a dead cyl, either from lost compression or an ignition problem, will still allow the motor to rev in Neutral.