help - 1999 Honda 90 leaking oil from upper unit

phiml

Cadet
Joined
Dec 8, 2007
Messages
18
Hi,

after each trip when i raise the motor up for trailing, a small amount of oil would drip out from the upper unit to the mounting bracket. I have look at it and could find where the oil leak from. Could it be the shaft seal?

thank you

philm
 

unclemike

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Joined
Feb 27, 2011
Messages
13
Re: help - 1999 Honda 90 leaking oil from upper unit

A lot depends on where the oil is coming from. If it is dripping out of the little tube (90 degree tube ) midway up the front of the engine, then oil in in the same area as your flywheel. Not good...

It could be caused by bad oil pan gasket, but could also be the lower crankshaft seal, or a rusted out seal bolt (which is steel) on the underside of the power head. This would be especially true if your shift shaft seal was torn and water got under the powerhead.

Before you go pulling the power head, remove the starter and look inside the starter hole at the flywheel. If there is oil in there, it will be pretty obvious.

Another way to check where the leak is coming from is to clean the oily area with brake clean. Let it dry. Then get a dry powdery antiperspirent at the drug store. Spray it in the area where you think the oil is coming from. Let is dry.

Then use your engine as you normally would and tilt it up as normal to get it to leak. Go back later and you should see the path of the oil.

There is probably something else like that you can buy at an auto parts place...but at least your motor will smell real good with the deodorant.

Mike
 

phiml

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Joined
Dec 8, 2007
Messages
18
Re: help - 1999 Honda 90 leaking oil from upper unit

Unclemike,
Funny thing, I have look at it before I raise the motor last time out and I couldn't find any sign of oil leak at all. But when I raise the motor up there will be 5-6 drop oils milky oil on the lower shaft cover. It is a big job to replace a gasket seal. So, what else should i have service while the shop remove the power head.

Thanks for your advice.

phiml
 

unclemike

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Joined
Feb 27, 2011
Messages
13
Re: help - 1999 Honda 90 leaking oil from upper unit

You have to find the source of the oil leak. You should be reasonably sure it is coming from inside the engine before you remove the powerhead. As I said, you can take out the starter and look inside where the flywheel is...and see if there is any oil there. There should not be any there.

Mike
 

phiml

Cadet
Joined
Dec 8, 2007
Messages
18
Re: help - 1999 Honda 90 leaking oil from upper unit

Hi Unclemike,
As suggested, I removed the starter and take a look inside the fly wheel. There is a little oil in the bottom corner. That explain it, there is a small oil leak and it is collected in the recess pocket. As I raised the motor up after each trip for towing, the oil got dump out from the pocket down to the out side.
Now, what Is my next step?

Thanks

phiml
 
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