Metal flakes in lower gear oil / on plug magnet

[gdeangel]

My setup is a 1997 SX-C, which saw very little use last season (10-15 hours total) since the last lower unit oil change. I expected I wouldn't need to change the oil this winter, but when I pulled the drain plug to inspect condition, I had a bunch of metal shavings on the plug magnet and some shiny flecks in the oil sample. Needless to say, the gear oil is getting changed, but what I don't know is what the best way is to proceed with finding the cause of the grinding.

This is the first season I decided to do the winter maintenance myself. When I got the boat three years ago, I had the shop check the drive alignment. I had an incidence at the end of the prior season where a line got wrapped in the prop and since then it's been a bit stiff to get into and out of gear, although I never heard any "grinding", but my suspicion is still that the problem is with the pinion gear assembly, but I am really just guessing. It's not like there was a lot of metal in the oil, but as it had so few hours and was still honey amber clear that I could see every fleck. Anyway I'm concerned enough to maybe even bring it in to a shop, although I don't think too highly of the one I had been using. If there's anything I can do on my own to try to assess the extent of the problem without pulling the drive, where should I start?

Thanks in advance for the advice.

 

[gdeangel]

Re: Metal flakes in lower gear oil / on plug magnet

I already wiped down the plug, but here's a pic of what was in the oil...

 

[Fun Times]

Re: Metal flakes in lower gear oil / on plug magnet

but what I don't know is what the best way is to proceed with finding the cause of the grinding.

although I never heard any "grinding",

Hi there, Just for clarification, How do you know there is something grinding?

I had an incidence at the end of the prior season where a line got wrapped in the prop and since then it's been a bit stiff to get into and out of gear,

When you had the line wrapped around your prop shaft? Did it cut into a seal and lose your gear oil?

Any major repair done due to the line wrapped around the prop?

Was the drive pulled off of the boat for service?

 

[jerryjerry05]

Re: Metal flakes in lower gear oil / on plug magnet

If your getting "chunks" I'd do some disassembly.
Single prop or duo?
Pull the prop shaft bearing carrier and you can see the pinion and gear.

Don't know why line around the shaft would make it stiff to shift.
No or little use can cause corrosion/gunk to build up and make it harder to shift.
I doubt you'd hear any grinding unless it's so bad it's jumped a tooth or stripped something.

 

[Grub54891]

Re: Metal flakes in lower gear oil / on plug magnet

When ya shift are you going into gear slowly? You should shift quickly,firmly so it grabs quickly. If shifting slow they tend to grind,creating shavings. At least in mercruisers.
Grub

 

[gdeangel]

Re: Metal flakes in lower gear oil / on plug magnet

Thanks for all the replies. The incident with the line didn't cause and seas to break / loss of oil. It was around that time the shifting became stiffer... when it happened the boat just died in drive. Not realizing I had tangled on a line, I tried to put in back in neutral and I had to really force the shift lever to move even an inch. We then figured out the problem and after untangling the line, we got the prop freed and I was able to get it back in neutral but it still seemed to move stiffly so it's possible that trying to force into N with the stuck prob maybe bent something?

The line was fine. The shop looked at it and recommended I replace the shift cable, and gave me what I thought was an inflated price, which made no sense to me, and that's around the time I got hold of a shop manual and started seriously reading up on doing maintenance myself. They didn't pull the drive, and it hasn't had any work done other than winterizing since then.

Slow shifting could definitely be part of the problem, as my wife is super "scared" to rev the engine when going into gear, and because the level is so stiff, it's hard to control and get in gear without "taking off".

If the drive needs to be pulled / realigned, I'm going to probably have to take it to a shop since it's just me and I don't have an engine lift or anything like that to move the drive around with. What is involved in pulling the prop shaft bearing carrier? (It's a single prop setup).

 

[skydiveD30571]

Re: Metal flakes in lower gear oil / on plug magnet

Head over to Boatinfo - boat brochures and manuals for boats and marine engines! and find the service manual for your drive. They are OEM manuals and free to read. Here you can read up on what is necessary to pull the prop shaft bearing carrier.

As for pulling the drive, many many people do it alone including me. Some people build simple drive stands to help them (you can find great ideas in the "Adults Only" section at the top of the threads page here), others just muscle it. I haven't gotten around to making a stand but I just pull the drive and set it aside to check on things, then reinstall it. If you have to carry it more than a few feet a stand will be a good idea.