10 HP upper crank seal

Brokeback Johnson

Petty Officer 3rd Class
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May 26, 2009
Messages
90
We are reviving a 1960 10 hp Evinrude and believe there is a seal problem under the flywheel due to the fact that the points had dark oil pooled on them......also a terrible coughing that is uncurable with carb adjustments.

Does this model use a rubber seal or slinger? How does the slinger act as a seal? My outboard manual shows crank assembly for all engines but the 10 so not sure what we've got here.

Any help appreciated.
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 10 HP upper crank seal

That model incorporates a Carbon Seal & O Ring assembly at the top main bearing area.

The coughing.... usually due to a fouled carburetor which needs cleaning andr rebuilding.
 

coolguy147

Commander
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Jul 14, 2008
Messages
2,817
Re: 10 HP upper crank seal

ya i got the same problem. dont replace it yet cause its a bit hard. clean the points gap .020 and run the motor for maybe 30 hours. check them again if they got oil then ur upper crank seal. i got to clean them generally every 3 months or 4. like maybe every 1000rpm it may puff out little oil. could be worse or better dont know. luckily it was just from sitting a long time.

but if ur motor hasnt been serviced please replace impeller and check compression

it weird cause for my motor like if i turn the high speed needle out 1/4 turn. and if i keep it slow idle it doesnt do it. then back to normal it misses then comes back. just annoying cause sometimes it stalls. i know my carb is clean. but if i run the motor. wide open for a few minutes. it will lessen dramatically. but if im going through a canal it will do it everyonce in a while
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
Re: 10 HP upper crank seal

We are reviving a 1960 10 hp Evinrude and believe there is a seal problem under the flywheel due to the fact that the points had dark oil pooled on them......also a terrible coughing that is uncurable with carb adjustments.

Does this model use a rubber seal or slinger? How does the slinger act as a seal? My outboard manual shows crank assembly for all engines but the 10 so not sure what we've got here.

Any help appreciated.

Joe is right, it has carbon seals, top and bottom. Just for info, the slinger method is amazingly simple and works. Any oil that creeps up the shaft is slinged (slang? slung?) off by centrifugal force. Then it is sucked back down to the intake manifold by way of a passage cast & drilled in the crankcase.
 

Joe Reeves

Supreme Mariner
Joined
Feb 24, 2002
Messages
13,262
Re: 10 HP upper crank seal

FR...... Isn't that a name of a song?..... Slinged, slang, slung, everybody's got one?
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
Re: 10 HP upper crank seal

FR...... Isn't that a name of a song?..... Slinged, slang, slung, everybody's got one?

I dunno, I lost track of the latest music after the "One Eyed, One Horned, Flying Purple People Eater" went off the charts.

Brokeback, black gooey oil often is the result of somebody over greasing the armature plate. The grease liquifies and slings all over everything. Oil from the bearing seal is clear like it was when you put it in the tank. But of course it adds to the other black cruddy stuff.
 

Brokeback Johnson

Petty Officer 3rd Class
Joined
May 26, 2009
Messages
90
Re: 10 HP upper crank seal

Thank you for the informative responses to my post. This is an excellent site!

We'll rule out the upper seal failure for now but have never been fooled this badly by a carburetor........still thinking air leak......the question is where?
 
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