Metal Filings in Lower Unit

[Principal Reeler]

Hi guys...

When lower unit oil was changed (1992 150 hp Yammie), mechanic made a note that there were "excessive" metal filings found. Haven't spoke to him yet.

Some filings are reasonable ??...just change the l.u. oil more frequently ????

I don't know just how excessive his "excessive" means yet.

Thoughts please !!! Thanks, Mac

 

[Porkchunker]

I'd want to look at the oil.

It is common to have some (not many) very fine flakes (almost like metallic paint). But if there are lots of flakes, or any particles you can feel when you rub the oil between your fingers, there is something wrong.

Better to have it pulled down, checked, new seals installed, and any parts replaced while the problem is still manageable.

A common reason for flakes/particles is when the clutch dog gets a chip popped off of it. The chip will get hammered into very fine pieces. When that happens, the clutch dog and the bearings need to be replaced. The particles will pit the bearings and thrust washers. Many times the gears are ok. Once the bearings start to go, they can take all the gears and sometimes the lower unit housing and prop shaft with them. I've seen the bearings get so hot they seize onto the prop shaft or warp it.

My recommendation is to have the work done...assuming you are dealing with a good mechanic with a good reputation, and not someone just trying to rack up some business.

If the damage is minor, they are easy to tear down, repair and reassemble. An important aspect is to replace ALL the seals and do a pressure and vacuum test to ensure the job is done right and water won't intrude into the gear case.

 

[Principal Reeler]

Porkchunker.....Thanks very much for your detailed assessment :!:

Mac