The last two times I have filled up our 89' Grady Overnighter it has had trouble starting right after. Last year, it would not turn over at the fuel dock. Last night, we got right out of the fuel dock no prob, then after we shut it down in the harbor, and then went to start up again it took almost a half hour to get it to turn over. Any thoughts? Seems at times it wants to turn, just can't.

Strange one.

Maybe filling is stirring up some junk and clogging the intake (pick-up tube) in the tank. After you let it sit, it settles again and you get fuel. Did you check the filters?

you said it won't turn over.. dead battery? loose cable?

not the battery. It wants to start, just wont. We try and then wait, try again. Then it starts ( or has to date) drifting inthe middle of the Harbor with a boat that won't start is not very cool....
It runs great out of the gate..

is it an omc by chance? I had a very similar problem with a 94 225 ocean runner. She would fire right up at the mooring but would refuse to start when hot. The mechanics never really were able to diagnose the problem until the number 3 cylinder seized.

Here are 3 common parts replaced on outboards with starting problems, I suggest a search on google for each to see if one fits your bill, best of luck -

Power pack
Stator
Voltage regulator

have you changed your spark plugs lately? cleaned em off? tightened them?
might be a loose plug wire, or a just a bad wire. i think.

Hi Johnnyc,

I have a friend with a small boat with a six year old 70 horse Johnson, it has a similar problem like yours. When the motor is being run onshore it will run fine, but in the water under load it won't restart, or it will bog down.

He's had the power pack and stator replaced, they've checked fuel and wiring, and two different shops have been unsuccessful.

He's had nothing but problems with this motor from the beginning, and is currently having a 75 horse Honda installed. He's giving up on the 2 strokes, problems could possibly be from the new fuel with ethanol.

Kind of uncommon in marine applications, but vapor lock.

Is it a fiberglass tank.fiberglass and ethanol do not go good together,know of two boats with that problem.What Van said.

They had to change their tanks,big bucks.

If the starter wants to turn but just can't seem to do it.Clean all your ground connections starter to battery.Battery to frame or block.Even adding another ground to the system is good for it.If that doesn't cure it then check your voltage at the starter.Possible rotted cables or connectors.If your sure you have good power and good ground and the starter still has problems starting when it's hot you may want to get it rebuilt.When is the last time you had it replaced or rebuilt ? If it is turning over fine and won't fire off then it could be fuel pump,fuel pump wiring,clogged line,stuck check valve if it has one.Hard to diagnose without knowing whether it's actually cranking and not firing or just not being able to crank.

Put me down for a supporter of the crap in the tank theory. It's happened in my cars before why not in a boat.
Slinger

The last two times I have filled up our 89' Grady Overnighter it has had trouble starting right after. Last year, it would not turn over at the fuel dock. Last night, we got right out of the fuel dock no prob, then after we shut it down in the harbor, and then went to start up again it took almost a half hour to get it to turn over. Any thoughts? Seems at times it wants to turn, just can't.

Hook up an external fuel source with known good fuel, may have to clean the crap out of the carb bowls too...

If you have a spinoff type fuel filter, remove it and pour the contents into a clear 16oz bottle. If there is separation, it will occur in minutes. What separates to the bottom is not water, but alcohol. The engine will not run on it. If that is the problem, change fuel stations or gerry can it. If you do not have a external filter, disconnect the fuel line and squeeze the priming bulb into the bottle.

if you have a digital multimeter do a voltage drop on yore grounds. PM me and i will give you instructions on how to do it

it would NOT TURN OVER at the fuel dock. Last night, we got right out of the fuel dock no prob, then after we shut it down in the harbor, and then went to start up again it took almost a half hour to get it to turn over.

Check if it is getting to warm .....had a car when it warmed up it had a hard time turning over until it cooled off some ....think the starter might have gotten hot

change the Thermostat & check if the starter is getting hot

If it wont turn over hot, it could be the starter. I'd start by seeing if the starter is getting voltage when it wont start.