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oil leak + mystery part- 1.8l 2017 242x

nclacrosse

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So we have had this boat for just about 1 year. Since new, I would occasionally see a really small amount of oil in the bilge area. I asked the dealer to check it out at end of season last year and they said they did not find any cause / leak. Recently the amount of oil I am seeing has increased (especially if we have been running hard pulling a big tube etc) and I now notice it in the bilge water. I did a little exploring today and the only oily surface I could find was under the starboard engine. Is this most likely an oil pan that isn't snugged down tight? Pretty sure the oil pump and cooler were not leaking.

MYSTERY PART - Also there is a cylindrical "port?" of some sort under the starboard engine toward the outer side that is not on the port engine? I thought the engines would be identical? I wasn't able to see under there but I drew a diagram based on what I could feel. It is smaller in diameter than the oil filter and almost feels like a sleeve with a cap pressed into it. Kinda like a 2 piece filter wrench or plumbing clean out port? Can anyone tell me what this is and why it only appear on 1 engine?

2017-242x-oil-leak.jpg
mystery-part.jpg
 

swatski

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So we have had this boat for just about 1 year. Since new, I would occasionally see a really small amount of oil in the bilge area. I asked the dealer to check it out at end of season last year and they said they did not find any cause / leak. Recently the amount of oil I am seeing has increased (especially if we have been running hard pulling a big tube etc) and I now notice it in the bilge water. I did a little exploring today and the only oily surface I could find was under the starboard engine. Is this most likely an oil pan that isn't snugged down tight? Pretty sure the oil pump and cooler were not leaking.

MYSTERY PART - Also there is a cylindrical "port?" of some sort under the starboard engine toward the outer side that is not on the port engine? I thought the engines would be identical? I wasn't able to see under there but I drew a diagram based on what I could feel. It is smaller in diameter than the oil filter and almost feels like a sleeve with a cap pressed into it. Kinda like a 2 piece filter wrench or plumbing clean out port? Can anyone tell me what this is and why it only appear on 1 engine?

View attachment 81097
View attachment 81098
There is nothing like that in parts... Very curious.
https://www.babbittsonline.com/oemparts/c/yamaha_sport_boat_2017/parts

EDIT: Also do not see anything in that spot in the service manual, although I have a manual for AR/SX/L/LS, not X (same engines though).

Could that be an anode? (oddly placed)


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Last edited:

nclacrosse

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Got a pic today and it's a plug ... Doesn't appear in any of the engine diagrams I have seen though.
It's also smashed up against the compartment floor, so I'm not sure how possible it will be to tighten it.

2017-242x-plug.jpg
 

swatski

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Got a pic today and it's a plug ... Doesn't appear in any of the engine diagrams I have seen though.
It's also smashed up against the compartment floor, so I'm not sure how possible it will be to tighten it.

View attachment 81186
Gee, thats odd...

@Neutron have you seen this in any newer skis? That is super odd, I think.

I think I would contact Yamaha if the dealer has no answers. Forward the pic to the dealer, too, as they can forward to Yamaha. I've never found a way to email directly, but they generally respond to calls.

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Cobra Jet Steering LLC

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Never noticed one of those on my engines, if you un bolt the motor mounts on one side of the engine you may be able to lift up that side enough to tighten it , but that is all I can come up with.
 

Betik

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okay I am going to say it...
did you try to move that mystery part ? It kind looks to me that it got stuck between the floor and the engine. I know crazy, but I had 2 plastic parts on my boat that NO ONE has been able to id. That included the entire service department at my local dealer.
 

Betik

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veteran please correct me if I am wrong. But would that bilge pump deactivate once it detects oil inside of it ?
If that is true, he might need a back up bilge pump installed real quick
 

MrMoose

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I agree with @Betik
get a coat hanger and use it to pull the cap out of there. Looks like someone dropped a cap and it ended up getting lodged under the motor.
 

Cobra Jet Steering LLC

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Also check your oil filter for leaks ,I just had a bad experience with a split filter case.
 

swatski

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I think @Betik is right! This is an odd part that does not belong. I bet it is trapped there!!!

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Neutron

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I think @Betik is right! This is an odd part that does not belong. I bet it is trapped there!!!

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I agree, not part of engine at all. Oil is coming from somewhere else.
Check oil cooler bolts where it bolts to engine.
 

F.M.

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I happened to find the exact same thing in my 2017 242x earlier this year. But instead of wedged under an engine it was rolling around in the bilge. I was told to put it back or the world would end.

https://jetboaters.net/threads/what-is-this.16742/
 

swatski

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okay I am going to say it...
did you try to move that mystery part ? It kind looks to me that it got stuck between the floor and the engine.
WINNER!!!!

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F.M.

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Also, on a related note..... the part that I found has been at the dump since March and the world is still spinning, the oceans haven't drained and no demon from hell has set my boat on fire yet.
 

swatski

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Also, on a related note..... the part that I found has been at the dump since March and the world is still spinning, the oceans haven't drained and no demon from hell has set my boat on fire yet.


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nclacrosse

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Update: looks like oil is coming from oil tube / union (banjo) bolt feeding the chain tensioner assembly. Was able to tighten one of the bolts a little. Everything else was tight, but I am still getting some leakage after running for a few hours. My guess is one of the gaskets is shot or has some grit on it keeping it from sealing correctly? Opinion - is this significant enough to take it in to dealer now or just keep an eye on it and wait until the end of the season? Oil levels are still fine and I assume if it was bad enough to be causing damage, I would see oil sprayed all over the engine compartment.
upload_2018-8-27_14-52-1.png
 

Beachbummer

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As long as you can keep the oil level fine during the outing you should be good. I would make sure you are topping off and monitoring carefully but... I would not lose a weekend over this...
 

JeffVans

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Judging by this and the other threads, I'm going with the mystery part being something for testing the engine prior to install. As for the oil leak, just keep an eye on the level. if you think you have fixed the problem by tightening the bolt, I'd spray the area down with some brakekleen (this will piss someone off I'm sure) and make sure its not residual oil leaking down from before. You could also try to replace the (what I'm assuming are) copper washers that seal it for about a dollar if its still leaking from there after its all cleaned up.
 

Scottintexas

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@nclacrosse what was the outcome on this? Did the leak stop? Did the dealer ever do anything?
 

Merlion

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