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Oil in the Spark Plug tubes

Boat~R~US

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Hello All,

So started to winterize the Rotax engines and when I removed the spark plugs on both engines prior to fogging the engines. What I found was a big surprise. Their was motor oil on top and bottom of the spark plugs, enough to cause drips of oil on the socket. These engines have 70 hour of use and it was the first time plugs were removed. (its a 2018 engines)

So what could cause this to happen on both engines? Plugs also looked pretty covered in oil. No engine performance issues and no large amounts of smoke.

Did Rotax have a set of bad seals ? Did they over torque or under torque? Like to throw this out to everyone and see if they ever heard of this issue... We are in a puzzle why this happened.

Thank you
 

JetTech72

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I wouldn't be to worry, but looks like your valve cover maybe leaking.
You can try to re-torque those 8 Torx screws.
Go in a cross pattern starting from the middle & target about 7 lbf.ft.
 

Cobra Jet Steering LLC

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Common occurrence when the valve cover gasket leaks , the oil collects in the plug recesses so try tightening the bolts or just replace the gasket
 

Boat~R~US

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Here is a follow up of what happened. Bad seals placed in both engines.... Check your plugs their might be more out there like this.
 

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At the Sand Bar Again

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So, Boat-R-US, what are we looking at? I am sorry, but I don't know where those tubes in your photo come from. I too had oil all over the top of the plugs when I changed them last week. I haven't tried to retorque anything yet. I was checking this forum for additional information and saw this updated post. Thanks in advance.
 

Boat~R~US

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So these sit below your spark plug housing. What it does is prevents oil from pushing up past the spark plug.

You can see nothing to do with torque or head gasket seal. The rings were bad because installer never noticed them or just installed anyway.

It’s a simple fix to perform and I recommend to order the service manual if your doing it yourself or if under warranty have the dealer do it.

Hope this helps
 

Mr.Happy

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Hello, i hope you can help me. I have the service manual, i can not found information from this part what i see on the picture, have you more information?
 

Mr.Happy

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my interst is, how i change the spark plug tubes. i have found the site in the book many thanks for this.

i hoped, i must not remove the cylinder heat cover when i will change the spark plug tubes, only a dream :-(
 

Boat~R~US

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It’s easy, but I really think you should get a professional to do it from what I’m reading .
 

Mr.Happy

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exactly, that's no small repair. by the engines is this from the first day. i will watch in the future if it will be more.
 
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