Fuel tank cleaning

[jcstriper1]

Hey everyone,
can anyone help me here with this issue?
First, let me say how this came about. I am helping my neighbor who is elderly who has a 21 ft. 1996 Robalo CC 2120 225HP 2 stroke. He wants to eventually sell it, but the thing is he has not started the motor in 8 years, i know not good. If by the grace of god this motor starts using seperate gas of course, his fuel tank will need a dam good cleaning or will need to be replaced. So the question is does anyone know someone who does this? Or does anyone know who does replacemnt of fuel tanks? The tank is under the console which holds a 100 gallons. There is only about 10-15 gallons in it now. Just don't know whether it's more prudent to get a new tank installed or have it cleaned. Thanks to all who reply. Monmouth/Ocean county works for me.
John

[Gerry Zagorski]

If there is only 10 gallons in there, I’d try and figure out a way to pump it out yourself.Otherwise you’d be hard pressed as an individual to get a fuel polishing company to come to you for 10 gallons. That or take the boat to a boat yard and let them deal with it.

If the fuel tank isn’t leaking I wouldn’t mess with it, drain the fuel and refill it.

[Duffman]

Some questions.....
Does he plan on using it at all or just get it running to sell it?
Have you spun the engine over yet?
Have you taken a look at the fuel or in the tank?

If he’s just selling, probably better off selling the way it is and be up front with potential buyer. This way he doesn’t have to deal with old gas/tank cleaning.

If he wants to get it running, I’d personally pull the plugs and fog the cylinders and be sure it turns over. Then change water sep and engine filters. Disconnect fuel line from tank and try firing her up running off a portable tank with clean fresh fuel to see where your at.

No sense in dealing with the main tank til ya know where your at engine wise. Just my .02

[jcstriper1]

Hi Gerry, I am worried about running contaminants through the engine such as sludge, bad gas etc. and causing any possible further damage. you agree?

Hey Duff, he wants to use for another year or two and he said he would sell it to me, so i have a special interest and want him to do it right.
Have not tried to turn engine over yet, is there a possibility that it is seized? The motor was underneath his carport out of the elements if that helps any.
So i should not try to start it before pulling plugs n fogging first?
Gas was off color a little.

[Duffman]

The fact it was under a carport def helps. Always a possibility engine could be seized but being a 2 stroke I doubt it is. Your biggest issue is what’s in the carbs. Prob some nasty gum and varnish to deal with.

How I’d go about it, and take this with a grain of salt because I’m absolute lunatic with maintenance and upkeep...🤣

Pull all the plugs and shoot some oil in the cyls. Turn over engine by hand to be sure it’s moving. Drain the carbs float bowls if you can. Pull off fuel lines from carbs to filters and blow them out with air. Change filter and water separator. Disconnect fuel line from tank and put in a portable tank with fresh clean gas. Don’t forget to pre mix your oil if it’s not oil injected. Pump primer ball till it’s hard (insert joke here) and crank her over.

At this point you’ll see where your at running wise. Lots more to take care of but that’s a starting point. Hope that helps. I wouldn’t worry about discarding that bad gas or cleaning the tank just yet until you know where your at.

[jcstriper1]

Duff, thanks for you help. I'm not engine savy I know a little bit of the basics, i'll have to watch some youtube to see how these things you mention is done. How long should this take the average person to do this??? And this is the FIRST outboard i would be messing with since i'll be the one doing all of the labor. I've worked on nothing but I/O's in the past that i had owned.This will definately be a learning experiance for me. Or do you recommend me taking it somewhere with my inexperiance? Any idea of a ballpark figure this would cost?
Trying to save my neighbor some money, but don't want to be over my head either.
Thanks Again

[Duffman]

No clue on cost as I do just about everything myself. Im sure others could chime in on what they pay labor wise for service.

If your hesitant, keep it simple and just do this....pull plugs and spray some oil in cyls. Charge battery(s). Briefly crank with key to see if engine spins. Change whatever fuel filters it has, prefill them with fuel. try firing it up.

[jcstriper1]

Duff, thank you very much!! I will give that a try and i'll let you know what happened. Looking at Wednesday to try. TY

[jcstriper1]

Hey Duff, Well i tried it out yesterday and the motor sounded positive, I didn't try to turn it over all the way but i got some noise. Just glad to hear that. Think i may need a new starter though, tough time turning the key. I would assume that it's not seized if i got some engine noise, right? Not sure if would fully turn over though.

[Duffman]

Define noise? There’s good noise and there’s bad noise 😂

Before condemning the starter I’d look at everything else first. Start at the batteries and work your way to the starter. Check every connection especially since sitting for that long.