BOAT SLOW TO PLANE OUT

[walligator]

Does anybody know why my 225 mercury optimax would take so long to plane out,engine worked great last year.Now it takes 20 seconds for it to plane out,rpm's climb up slowly,no alarms, runs, idols starts like new.Any info would be greatly appreciated.If I put the throttle all the way down it takes off real slow and won't get on plane.If I slowly put the throttle down it will eventually get on plane.Top end is no problem once on plane.Boat does not miss at all.

Thanks,Walligator

[Valv]

First thing to do is check compression. After that everything is much less expensive and easier to fix.

Did you change prop ?

[walligator]

No change on prop.Motor runs great,just not planing out after winter storage.

[Farley]

Do you have a bunch of water in your boat or heavier gear like more batteries, bigger fuel tank or anything like that? If nothing else, try putting hydrofoil on the motor. They get you on plane faster.

[walligator]

Not really any extra weight,filled the boat up which is 59 gallons.Did that last year also and never had a problem.Only had 2-people in the boat.

[Surface Tension]

Any extra wieght in the stern? How about your trim? If your trimmed up its going to take longer to plane out. Was the engine fogged last fall before you put it away and did you replace the spark plugs after you burned off the fogging agent this spring?

[Hibbing]

Anchor up?

[walligator]

Motor was trimmed all the way down,until I planed out.Shot some oil in the plugs for storage but never changed them.Engine runs great and top end is same as last year.RPM'S just climb slow.

[walligator]

Motor also has an automatic jack plate.Not quite certain how it works,but never had to touch it last year.

[Dave]

You may have stubbled onto your answer all by yourself. A jack plate, I believe, raises or lowers your outboard. And you say it's "automatic". I'm not real familiar with jack plates but when something's "automatic", there would be a doubt in my mind if the boat didn't perform like last year and you're doing nothing different.

[Surface Tension]

AH, you have a jack plate. I think Daves right here. Since your not getting the hole shot but top end is what it should be your jack plate may not be lowering the outboard at slow speeds.

[ChuckN]

I've never seen an automatic jackplate, usually they are manual for the operator to manipulate the motor height to increase speed, performance.. Did you get an operator manual for that jackplate? If not, you might want to see if you can get one online and read about it.

Are you running last year's fuel?

I had issues similar to your issue last year when I bought a used boat with a 175 EFI. Turned out the owner did not treat the fuel properly. There was water in the fuel, and the fuel just plain decayed over the winter. No alarms, nothing like that. It just did not want to go, but when it did...it went. I had to drain 30-40 gallons from the tank(I topped off the tank not knowing there was a problem).

Your motor should have a water/fuel seperator (it's also a fuel filter). On my motor it looks like a car's oil filter. That should collect the water out of the fuel.

[RossT]

A common problem with Opti's... change out your spark plugs. Add fresh fuel some Sea Foam, you should be good to go.

A hydrofoil fin won't do that boat/motor any help, you've got 3.0L V6 pushing it. The motor just isn't living up to its potential.

[walligator]

Thank You very much for all the responses,my boat is up on vermilion right now,I'll be up there this week end and see if I see any action with the jackplate.I would think bad gas may buck on you.I know I put plenty of stabil in the gas this fall,but I will sure put some seafoam in this weekend.Chuck,when you had bad gas did it actually start out real slow and struggle to get on plane and then accelerate to plane and not miss at all?

[ChuckN]

I had such poor fuel that the motor wouldn't run at idle at first, and it definitely struggled to go when I had it running. After I drained most of the bad fuel and added fresh fuel, yes, you could notice hesitation for awhile, but there wasn't much for "misfiring" activity.

I also switched oil to Amsoil DFI full synthetic and that made a world of difference in performace also.

You might want to consider new plugs like someone already mentioned. I've heard of that too. Opti spark plugs are spendy.

[upnorth]

I would suspect the issue with the jack plate or a trimming issue. I would think if it was bad gas you would see an overall performance issue.

Have you checked to be sure that the motor is physically lowering all the way back down, gauges lie?

[walligator]

yes,I know the motor goes all the way down,I tried when I pulled the boat out of the water.

[Dave]

I'd do what Chuck suggests first, find an operator manual for the jack plate; to see if that is operating properly.

[walligator]

I just found out the jack plate does nothing but bring the motor down.It is permanentdoes not move up or down.