WTF is this? Optimax experts please.

[TraceF3]

Just got a new to me 2007 Opti 250xs with a Sportmaster lower. Pulled the prop to change the L/U lube and this was inside the housing. I just reached in with my index finger, jiggled it and it fell out. I'm amazed it didn't get between the prop and housing before it was found.

It appears to be part of a casting. Painted black. Any ideas what it is?

[XstreamVking]

I'm gonna guess part of the tuner....

[TraceF3]

How could it get broken off and down in the lower unit exhaust?

[FMP]

Probably just that a booger of casting. It just followed the ex flow and gravity and stopped where you found it.

[TraceF3]

Are you saying it may have been there for 11 years?

[TraceF3]

It was covered in greasy black soot but the inside of the prop is nice and clean....

[Da Bull]

Well it`s lost foam casting. Have you checked compression?

[TraceF3]

I haven't. But I had it surveyed. The surveyor checked it hot after running on the hose and said compression was even across all 6.

[FMP]

Might just have dropped down a couple hrs before you found it, new keychain.

[Capt.Insane-o]

Well, it's not a wrist pin, so you should be ok :)

[Dave S]

Wrist pins should not be in the lower housing.... found one in an exhaust port tho....Merc thing....

[FUJIMO]

https://www.screamandfly.com/attachment.php?attachmentid=419416&d=1538171505 (https://www.screamandfly.com/attachment.php?attachmentid=419416&d=1538171505)

[FUJIMO]

https://www.screamandfly.com/attachment.php?attachmentid=419419&d=1538171585 (https://www.screamandfly.com/attachment.php?attachmentid=419419&d=1538171585)

[FUJIMO]

https://www.screamandfly.com/attachment.php?attachmentid=419418&d=1538171556 (https://www.screamandfly.com/attachment.php?attachmentid=419418&d=1538171556)

[FUJIMO]

https://www.screamandfly.com/attachment.php?attachmentid=419417&d=1538171539 (https://www.screamandfly.com/attachment.php?attachmentid=419417&d=1538171539)

[FUJIMO]

https://www.screamandfly.com/attachment.php?attachmentid=419415&d=1538171488 (https://www.screamandfly.com/attachment.php?attachmentid=419415&d=1538171488)

[TraceF3]

https://www.screamandfly.com/attachment.php?attachmentid=419415&d=1538171488 (https://www.screamandfly.com/attachment.php?attachmentid=419415&d=1538171488)


Much better!










.

[TraceF3]

OK so what IS a tuner and how could a piece get broken off and in my exhaust housing?

[FMP]

Any takers on that question

[TraceF3]

O Googled and it looks like a section of exhaust header? But if a piece is missing what effect does that have?

[TraceF3]

I Googled

[FMP]

Interesting dimpling texture on part of it.

[tux974]

Take the lower unit off get a flash light and look up into mid section/can.

[silverfox]

The dimpling look is probably from the lost foam casting process. Or maybe it is a piece of octopus skin. LOL
Bill

[XstreamVking]

https://www.boats.net/catalog/mercury/outboard-by-hp/250hp/1e000797-thru-1e002341-usa-cat-90-889352006-xs/driveshaft-housing-and-exhaust-tube
Here's the parts breakdown The tuner is #20

[TraceF3]

Take the lower unit off get a flash light and look up into mid section/can.

I thought I'd do this today. Found some fluorocarbon line around the shaft and when I pulled it off a lot of it was up into the seal so I need to take the lower in and have the prop shaft seals redone anyway.

[FMP]

Lost foam for the tuner or did it pass a kidney stone? Almost

[David - WI]

419521
419523
419522

[CUDA]

Meteorite

[TraceF3]

Meteorite

Now we're getting somewhere!

[TraceF3]

Mystery solved.

Previous owner tried to "improve performance" by drilling holes in the can. You can clearly see where it broke off two pieces of the tuner. I guess one piece came out some other time. I can only find one.

Does this do any harm? It's hard for me to believe it helps anything.

[FMP]

Pretty clean up there

[XstreamVking]

Just weakened the mid, IMO is all that did.