Metal Shavings

ax1lla

Seaman
Joined
Oct 8, 2009
Messages
60
Hi all,

I know there are a lot of threads out there on this, but....I'm still not sure what course of action to take. My boat is a:
1974 Sterncraft
Outboard
Mercury "Tower of Power" 115

I have noticed metal shavings on the oil plug for at least 5 years or so. I've honestly never really looked at the oil itself though. Anyway, I bought the boat about 12 years ago for $400. It has started from day one and my family and I go every year with the exception of two (because of the algae bloom). Last year (2021) was a year we never took it out (or started it).

When I changed the lower engine fluid today, I notice the oil smelled really bad. Also, I have a lot of big metal flakes on the oil plug. Plus, I'm assuming what looks like metal flakes in the oil (see attached pics).

I've always said that I will ride this boat until she dies, then sell it and break even or make a little. That being said, I don't really want to break down in the middle of the lake with my family. Maybe it's time to get out while the getting's good. Is this something that I should be concerned about and am on borrowed time? Or, is this not that abnormal and I could possibly keep running it for years longer? I'm torn. Everything I read about this is mixed. I see many posts that talk about how serious this is. I see many other posts that say metal shavings in the oil is pretty normal. Any advise? Again, I'm not going to put money into this (replacing engine parts, fixing, etc.).

I appreciate your thoughts/advise.
 

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racerone

Supreme Mariner
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Dec 28, 2013
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Not looking good.-----Do you ease it into gear or do you shift with a quick firm motion ?
 

ax1lla

Seaman
Joined
Oct 8, 2009
Messages
60
Not looking good.-----Do you ease it into gear or do you shift with a quick firm motion ?
I ease it in, but...I can feel it sort of clunk into gear if that makes sense? Been doing that for some years now. Is it something that I can maybe get a few more years out of? Or, would you advise selling now while it's still running?

Like I said, I don't want to put any money into it. I got the boat for a steal and it's given my family and I awesome memories for over 12 years. But, I always told myself I'd get rid of it when it started having issues. I'm tempted to ride til it dies, but....I get anxiety just thinking about being stuck on the lake with my family. It's happened 2-3 times before (with others) and it wasn't a huge deal because we luckily were able to get people to help tow us in. But, I know it won't always be that easy. I'm torn.

Also, why would the oil smell? I didn't even take it out last year, so that surprised me.
 

racerone

Supreme Mariner
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Dec 28, 2013
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Even new oil smells. ---You are supposed to shift with a quick firm motion.---Easing it onto gear does the damage.
 

Sea Rider

Supreme Mariner
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Sep 20, 2008
Messages
12,345
How many times have you changed the gear oil since your ownership ? Should be changed avery 100 metered run hours...

Happy Boating
 

ax1lla

Seaman
Joined
Oct 8, 2009
Messages
60
How many times have you changed the gear oil since your ownership ? Should be changed avery 100 metered run hours...

Happy Boating
I change it every year (once a year). I go out about 5-15 times a year depending.....
 

ax1lla

Seaman
Joined
Oct 8, 2009
Messages
60
Even new oil smells. ---You are supposed to shift with a quick firm motion.---Easing it onto gear does the damage.
To be fair, I don't let it sit in the in between "engaging" part. I guess I am just saying I don't slam it into gear.
 

racerone

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Dec 28, 2013
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But you are supposed to shift quickly from neutral to avoid grinding the clutch dog on the spinning gears !!
 

Sea Rider

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Sep 20, 2008
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Any thoughts on my original question?
If the pinion bearing hasn't gone south already should find repetitive metal shavings at future gear oil changes. As this is a second hand motor probably the previous owner changed the gearbox components that were installed with inappropriate shims and washers, that's with too darn tight pinions against each other that will account to produce excessive metal shavings till finally wears in. As you don't want to spend any money on that motor use it until the F propulsion cancels out....

Happy Boating

 

merc850

Commander
Joined
Jul 7, 2010
Messages
2,046
You can check the gear lash by having it in N remove the prop and gently turn the propshaft back and forth, if it moves a little with some tapping it should be OK. If it turns a lot you have a shimming problem! Push the shaft in and out to see if there's end play there shouldn't be any.
Also if that's an O-ring on the drain screw I would replace it with the gasket for that purpose; drain and refill the LU (synthetic lube might give you a few more seasons).
Check the control cable to see if it's going all the way into forward - if that control box is 1975 era it should be taken apart and greased.
 

racerone

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?//----How can you check gear lash in neutral by turning the propshaft.---I need to know.
 

merc850

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?//----How can you check gear lash in neutral by turning the propshaft.---I need to know.
I'm saying that if it's really bad the shaft will rotate more than if it's within spec. (Should've said Forward)
 
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Sea Rider

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A gearbox with already shot pinion, bearings won't say much at all. The gearbox lash is something that comes factory adjusted to each motor brand specs. Inside a gearbox there's many shims and washers diameters to play with and proper tooling to adjust spot on proper gear lash. It's normal for any prop to have a slight rear/front shaft play. It's not a fixed thing.

Motors that have an attached magnet on the lower oil plug seems to take much longer for the pinions to break in nicely compared to motors that don't have such magnets like Tohatsu. Have never found not even metal fillings when changing gear oil on such brand motor.

Happy Boating
 

racerone

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There are many good motors that do not have shims.---Precision made so no shimming required !!
 

Sea Rider

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Sep 20, 2008
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12,345
There are many good motors that do not have shims.---Precision made so no shimming required !!
All pinions are precision machined worked, the shims are used to provide the correct lash between pinions to wear in nicely, will asure that all lower legs use some form of shims upon further investigation...

Happy Boating
 

racerone

Supreme Mariner
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Dec 28, 2013
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Sorry----There are no shims required in many Johnson / Evinrude gearcases,----For example a 1996 30 HP.----No shims listed anywhere in the parts book !!!
 
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