99 Johnson, 99 seaswirl (18ft) oil?

Bluefish1984

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Jul 8, 2011
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possible dumb question here. (new boater) ive looked in my manuals and cant find how much oil my boat can take. i got a low oil light the other day and put it in about 4 qts. about done w the day (running thru the night), the light came back on... little help?

Thanks.
 

TD_Maker

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Aug 31, 2005
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Re: 99 Johnson, 99 seaswirl (18ft) oil?

How much gas did you use? A 2 stroke engine will burn the oil right along with the gas; moreover, I think your VRO oil tank holds 3 gallons, so its entirely possible you burned two qts (or more) of 2 stroke oil. If you only put in one gallon, it may be about time to again add oil to your tank.
 

Chris1956

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Re: 99 Johnson, 99 seaswirl (18ft) oil?

In my experience the oil tank will take about 1 gal of oil, when the "oil low" light or alarm comes on. That sounds normal to me.

The issue is how much oil did the OMs system mix with the oil? It is supposed to be 50::1 or 60::1. Did you burn 50 gal of gasoline, after you filled the oil tank in the morning? if not, the motor is over oiling, which can happen. Check all gasoline line connections and the main strainer under the airbox for air leaks. Air leaks will cause overoiling.

BTW - you should see all kinds of smoke from the motor if it is over oiling. Did you see it?
 

Bluefish1984

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Re: 99 Johnson, 99 seaswirl (18ft) oil?

its 50:1, i know that for sure. and smoke... nope, just your typical little bit of white smoke for a 2 stroke. from what you guys are saying.... when i bought it, the owner topped off the oil he said. so, since then ive burned thru 3 maybe 4 tanks of gas. and i believe its a 32 gal tank (??) on the boat. i intially mixed oil w the gas, then was informed not too since its automatic. so, i think i just need to dump more then a couple qts. in this time...
 

TD_Maker

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Re: 99 Johnson, 99 seaswirl (18ft) oil?

What size motor is this? Is your oil tank under the cowling or motor hood?
 

Chris1956

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Re: 99 Johnson, 99 seaswirl (18ft) oil?

Bluefish. Fill the oil and gas tanks to the top. Now go boating. When it is time to refuel, note the amount of gas the boat takes to fill back up. Now predict how much oil you will need for that amount of gas, based upon a 50::1 ratio. A pint for every 6 gal is 50::1, so if you add 24 gal gas to fill the tank, figure 2 quarts of oil should have been used.
 

Bluefish1984

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Jul 8, 2011
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Re: 99 Johnson, 99 seaswirl (18ft) oil?

TD: its a 115 Johnson. oil is under the cowling.... Chris, that makes sense now that YOU said it. its the same ratio i would use to mix it (if i were to mix it). thanks for the help!
 

Chris1956

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Mar 25, 2004
Messages
28,100
Re: 99 Johnson, 99 seaswirl (18ft) oil?

Bluefish, Isn't the oil tank located in the boat? I thought only Merc had oil tanks on their motors.
 
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