Changed oil now won't run

[Jon 1]

If anyone can help please! My friend changed his oil on his 08 mercury 90hp 4stroke. He refilled the oil through the dipstick and when he took his boat out it ran fine for about 15-20 min. Then it started sputtering and died. He had to start it up several times to make it back to the dock and now it will not start at all. I think it's because of the way he filled it and he thinks it's bad gas! Any ideas? Tia and please no rude comments

 

[Jon 1]

By the way he filled it through there because he didn't see the fill hole on top

 

[johnnygjr]

Very vague and confusing question.

 

[Jon 1]

Very vague and confusing question.

Not really that confusing... Either you will or you won't mess up the motor by filling it through where the dipstick goes?

 

[haventaclue]

You won't mess anything up by filling through the dipstick but I think he may have overfilled it and has blown something inside.Probably bearings,pistons,rings,etc. etc..I don't know anything about 4stroke outboards,basing this on what I know about cars.

 

[racerone]

How often did he change the oil ?---------How much oil was in this fine machine when he drained it this time ?