F9.9 metal in oil

[Coreylaker]

I put my '05 9.9 on my Jon boat an fired it up for a first spin around the lake yesterday only to experience declining power, a subtle knocking noise and ultimately found the fresh oil I put in it to be almost gray due to all the shaving in it. Water pressure/temp was fine. Though I have zero clue what's happened, clearly something is terribly wrong.
Does anyone have an idea?
Is it worth rebuilding and if so, how much might I have in parts and machining?
Thanks

[TownsendsFJR1300]

Sounds like water in the oil and the knocking, likely a bearing gone south at the very least.

To give an estimate on the repair you'll have to dig a bunch deeper, likely splitting the cases (not cheap if paying labor)

http://www.boats.net/parts/search/Ya...201/parts.html

If your paying someone labor to inspect, possibly replacing cases, its likley a parts motor or just try and find a rebuilt long block..

Please post what the outcome is and good luck..

[Coreylaker]

Thank you for your response. There is no water in the oil, but something has clearly gone very, very wrong. The oil(brand new before this 30min run) has so much metal in it that it looks like silver metallic paint when in sunlight. I haven't had time to begin dismantling and am completely bewildered by what would cause this to occur. A neighbor suggested it may be the spark advance mechanism freezing in place and its lack of movement has caused premature/retarded spark which can cause the motor to fail. Seems odd to me given it ran not great, but ok. It did seem to have an unfamiliar knock, however.
Any further guesses? The mystery is driving me nuts and because this is at my cabin 3hrs away, I won't have a chance to dig into it until spring chores are complete or I can make room in my small car to bring it back home.

[TownsendsFJR1300]

Not that it'll matter much but put a magnet adjacent to the metal parts (the shiney in the old oil) and see if their aluminum or steel(most likely aluminum).

I'd also try calling the local Yamaha dealer and check on any recalls for the engine. My F150 had a re-call for the very heavy duty balancer. If left without replacement, I was told it could destroy the engine. The balancer has two steel, looks like mini crankshafts geared together (but very heavy duty), in an aluminum housing. I could see those, if failed, making a bunch of noise and eventually spitting out its own aluminum case.

Looking at the parts fisch for your engine, you don't seem to have an separate balancer, just the balanced crankshaft itself. Something in the lower, rotating unit, has failed causng metal to metal contact

[rodbolt17]

actually, the balancer doesn't disintergrate.
it simply sheds the nylon driven gear teeth which then clogs the oil strainer in the sump which can lead to engine failure.

the theory about timing, best I recall that motor electronicly advances the ign.

its time for a teardown and inspection.

[TownsendsFJR1300]

its time for a teardown and inspection.

I ddn't see any easy acess plates to peek inside the crankcase for this engine. Can I guesstamate the only access is splittling cases to access the rotating assembly?

[rodbolt17]

its going to involve removing the gearcase.
removing the power head.
COMPLEATLY dissasembing the head and block assy.
then if its worth reassembling removing and cleaning the oil pan and strainer assy.

its not going to be cheap nor easy.
motor blowed up.
motor no good.

the cost of repair is going to rely on what failed and what is still usable.

[TownsendsFJR1300]

Tks.. Sorry for the op....

[Coreylaker]

I found a 9.9 short block on eBay for $250. The seller has excellent ratings.
Any thoughts?
Mark

[rodbolt17]

if you need a shortblock that's a decent price.
its a teat on a boar hog if you don't need it.
my experience with outboards and fleabay isn't good.

[TownsendsFJR1300]

I found a 9.9 short block on eBay for $250. The seller has excellent ratings.
Any thoughts?
Mark

Cheap enough!! If you can do the swap, it'd likely be worth it. If he a video of it running, even better.. Any warranty (30 day or ?)

Also, ask why he selling a short block?

Did the LU blow up or hit something? If it did hit something that hard, did any of that impact transfer to the crank/ block. And lastly, does it include the head(short blocks don't usually, at least referring to car engines)

I would use my credit card, thru Pay Pal should he sell you a POS, you can contest the charges(especially with the CC). You'd be pretty safe if you paid fo it that way.

[Coreylaker]

No, the motor never hit a thing but it was submerged last fall(fresh water) for an hour or two. I pulled the plugs, removed the carb, drained everything and had it running on the stand before I laid it up for the season(indoors/heated area). The disaster occurred during the first run of the season and though it ran after, have to feel the submersion had something to do with it.

[99yam40]

I believe he was referring to the e bay block, but it was interesting to know what happened to yours last year

[TownsendsFJR1300]

Yes, I was referring to the E-bay motor as 99Yam40 stated.

I suspect, on your broke motor, you may still have had some water, perhaps in the oiling passages and a bearing ran dry (no oil at least) and gave up the ghost...

For it to blow for NO reason, is very unusual.

If you can, and get the other other, engine, I'd part out whats good on your short block and re-coup some $ back..

[Coreylaker]

That certainly sounds like a plausible explanation of what went wrong. Makes me wish I had come here for advice on the submersion rather than assuming draining and replacing the oil was sufficient.
It'll be interesting to find the source of the trouble.