oil leaks through centre of the prop 1987 20hp

[Jackfish]

After I ran my motor on the stand today there was oil and water leaking out the centre of the prop after I shut it down.<br /><br />So...there is a seal that needs replaced....my question is what seal.<br /><br />I removed the prop and then the plate (#57) behind the prop with three small bolts that hold it in place and then I removed the 2 1/2" o-ring (#56), it looks ok but is that the seal that is failing or do I need to go deeper?<br /><br />It looks like I need a special tool to remove the bearing housing (#53). I also noticed that it is a reverse thread.<br /><br />Am I on the right track?

 

[joblo33]

Re: oil leaks through centre of the prop 1987 20hp

That engine uses thru-hub exhaust, are you sure you aren't just seeing exhaust oil? Drain the lower unit oil and check if it's milky, if not it was probably just exhaust oil.<br />Eric

 

[Jackfish]

Re: oil leaks through centre of the prop 1987 20hp

This is gear oil that is leaking. I drained the gear case and the oil in the gear case seems to be clean. I think the oil is mixing with the water in behind the prop and up the exhaust channel. The motor was not in the water I was just using muffs on it today, and it only ran for about 10 min.<br /><br />Can I pull the shaft seal (#55) without taking out the bearing carrier (#53) and is this the only seal that holds the gear oil in the gear case?

 

[AMD Rules]

Re: oil leaks through centre of the prop 1987 20hp

Did you run it on muffs, or in a tank? I'm thinking the same as Eric... may just be water/exhaust mixing.<br /><br />Your nose may help you distinguish between gear oil and engine oil. Gear oil has a strong odor. When you check the lower unit oil for moisture, you'll smell it.