Mixed the wrong oil

[joectran]

I have accidentally mixed my used oil 5W30 from my lawn tractor into the gas tank for my 2 cycle boat motor. The engine is running very rough now. I have dump the rest of the gas tank.<br /><br />Would like any advice on how to clean up the motor or what damages I have done.<br /><br />Thanks

 

[LubeDude]

Re: Mixed the wrong oil

How long did you run it that way? Chances are that you just have fouled plugs. Dump the gas and oil, put fresh gas and oil in and change the plugs, probably will be fine. Might have to change the fuel filter also incase some crud got in the old oil.

 

[JB]

Re: Mixed the wrong oil

To General Outboard

 

[ZmOz]

Re: Mixed the wrong oil

There isn't much you can do to "clean up" your motor. If it still runs bad on fresh mix, you probably damaged something. Spark plugs could be dirty, but other than that the new gas will clean out the 5w30. A can of seafoam wouldn't hurt.

 

[crazy charlie]

Re: Mixed the wrong oil

If you took notice right away there probably is no damage.Many of the older motors were run on regular oil mixed with gas.Some old timers have told me that in a pinch you can use fuel that way.Get some fresh fuel in it and add a can of seafoam and let it run through.As a matter of fact if you have not refueled yet,put about 5 gals of mixed fuel and a can of seafoam and let it idle for a while.Clean plugs when done.hope this helps.Charlie

 

[BillP]

Re: Mixed the wrong oil

You ruined the motor...I'll buy it cheap just to get it off your hands. Not really...but I'll give 99.99% odds that you didn't hurt anything. Motors are more durable than that and the oil isn't that bad for a short run. My guess is the rough running is fouled plugs.

 

[ZmOz]

Re: Mixed the wrong oil

What motor is this? I know that Mercury inline 6's run surprisingly well with no oil at all...

 

[Terry H]

Re: Mixed the wrong oil

Joe...there's not much damage you can do running with that oil except as some have said you may foul the sparkplugs...but if ran less than 20 gallons of the fuel mixed with the 5w30 you would only foul the plugs if they were needing changing anyhows. Over the past several years I have used 10w30 in a pinch more than I care to admit...I always decarb soon afterwards anyways...no worries.

 

[Ben Konopacky]

Re: Mixed the wrong oil

Hi Joe ; If anything major need to be done if there is no filter between tank and eng.is to do a good carb cleaning there is a lot of $uit in drained oil and very small orifices in the carb.

 

[Terry H]

Re: Mixed the wrong oil

Joe...I didn't see the used oil part...but I take it you didn't even use a full tank mixed at 50:1 so I shouldn't think you'd have done any permenant damage...I have a 60+year old outboard that still runs good, and for the first 30 years of it's life it was run on used crankcase oil mixed with gas at 16 or 24:1. It's a 2hp motor and these days I let the neighborhood kids use it on their jonboat...