Metal in my lower unit

[Jonbass]

" I bought my boat used last y

" I bought my boat used last year and drained the lower unit oil before winter set in. This is a '90 Johnson 150GT. Found very little oil in there and it was black and filled with metal dust. This year so far, I've drained the lower unit 4 times, and though I'm not leaking any oil, it's coming out very dark, almost black. What's more troublesome is I'm seeing a lot of metal dust in the oil andon the magnetic tip of the screws. Last oil change , I found some larger filings. I know this can't be good. I also hear a clicking when I spin the prop by hand while on the trailer. I'm thinking this could be a bad clutch dog slowly being eaten away. Is my lower unit nearing a major breakdown? "

 

[joereeves]

"Jonbass....The very black lub

"Jonbass....The very black lube that you mention really isn't cause for alarm. Years ago, lower unit oil had a great deal of (this is no joke) whale sperm oil mixed in with it, and that was as black as can be.

The metal filings on the magnet tips... It's normal for very small metal filings to collect there. They would have a rather fuzzy appearance to them. However, any large slivers or splinter like pieces of steel would be cause for alarm.

The clicking sound you hear when you turn the prop indicates that the shift linkage is out of adjustment and that the shifter dog, instead of being aligned evenly between forward and reverse gear, is actually close enough to one or the other for the shifter lobes to touch. Adjust the shift cable at the threaded trunion portion (where the shift cable clamps to the engine). Unless the engine jumps out and into gear (feels like you hit something) when underway at a high rpm, the gear and shifter dog lobes are okay.

Joe

"