too much oil... dumb mistake!!!

slyshar3

Cadet
Joined
Jul 23, 2004
Messages
29
I have a 2006 Johnson 15 hp 4 stroke outboard that started cutting out and missing badly at higher rpms. I took it home and found out it had 1.5 qts too much oil in it. I can't figure out how I did that!! The oil looks good that I drained and comp is 125/150. It starts and idles great but refuses to rev up. What could I have done to it. Any help would be appreciated and any ridicule is deserved!
 

kenmyfam

Supreme Mariner
Joined
Aug 10, 2006
Messages
14,392
Re: too much oil... dumb mistake!!!

How much is meant to be in there ???
Too much by a large percentage can blow oil seals and cause all kinds of problems.
The compression difference between cylinders that you state is excessive in my opinion. 125 and 150. although both high readings, that could be an issue.
 

samo_ott

Vice Admiral
Joined
Jun 18, 2006
Messages
5,125
Re: too much oil... dumb mistake!!!

I agree. 1.5 quarts too much? That's a helluva lot of oil too much, where did it all go? How much goes in it normally?
 

slyshar3

Cadet
Joined
Jul 23, 2004
Messages
29
Re: too much oil... dumb mistake!!!

What seals can blow? What are the kinds of problems that can be caused? The compression is pretty good (redid it today) but it still wont rev and there is a buttload of oil comming out the exhaust. I think a certain little boy may have been trying to help dad out. Anyway, Where should I start looking.
 

jbjennings

Captain
Joined
Jul 18, 2007
Messages
3,903
Re: too much oil... dumb mistake!!!

I hate to say it, but your 4-stroke shouldn't be putting out a lot of smoke. I think the seals they're speaking of are internal such as crankcase seals and such. The oil burning does sound like somethings leaking crankcase oil into the cylinders. Maybe it just blew out your valve seals but I know very little about 4-stroke outboards so can't be of much help. If it were me, I wouldn't run it much more with it smoking real bad or it might build up carbon under the piston rings and really do some damage.
Let someone who knows 4-stroke outboards look at it. I don't think those motors are something a shadetree can handle. But since I don't know much about them, that could be bad advice.
I hope you get some good news, my little helper has "helped" Dad out a couple of times, too! :)
JBJ
 
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