Oil in air box?

Checkswrecks

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That's a bit much. Start with cleaning it and the vent out. Under the lower left corner of the airbox is a very short capped tube. A number of people have replaced that with a longer tube and cap to be able to periodically check &/or drain.

The color bothers me more though. Suggest opening the radiator to see if you have oil in the water.
 

Ride

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What vent are you referring to that I should clean out?
When adding a drain tube do you mean I should add a line with a cap at the bottom (to keep an eye on it)?
 

gapmtn1

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What would cause the oil in the air box?
Should the fuel line have clamps?
Oil comes from crankcase breather. It's the opening that is nearly dead center of your airbox (in red, below). Vapor comes in, your bike breathes and burns it. Some of the oil vapor becomes liquid.
Fuel tank vent at immediate foreground has correct old school clamp. I believe that thing with the blue tabs is your fuel supply line coupling... it is downstream of your fuel pump (in tank) so the fuel at that point is pressurized.

breathe.png
 

Ride

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Sorry let me clarify :

Is it normal to have so much oil in the air box? I understand there will be some. Honestly from what I’ve read it seems normal considering how little maintenance I think was seemingly done.

For instance the logbook and receipt shows valves checked at 26k miles. Bike is at 33k currently. Would they really skip plugs and an air filter!?



Should these ends of the fuel line have clamps?

 

Top Ten

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Depending on the traffic conditions where you ride the air filter might be normal.

But those plugs! That does not look like 7K worth of riding on those plugs. It looks like they did skip the plug replacement and/or it looks like you are running a very rich air-fuel ratio (AFR). It also looks like you're getting water in the plug well on the far right. They do not look good or normal. New ones are in order and change them according to the Yamaha maintenance intervals. Even when plugs look good they suffer wear that causes stress on your ignition system.
 

Ride

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I’m a fanatic with maintenance. Mostly because I enjoy it as a meditation but also due to the fact I didn’t buy it new and don’t trust anyone to work on my stuff. Too many corners are cut.

For instance I picked up NGK plugs from Rock Auto. Then I remembered about the fake NGK thing. So I looked on the website and found NGK doesn’t list them as an authorized retailer. Doesn’t mean they aren’t either. I went to 4 different authorized retailers to find someone who had them in stock then compared the two.

Still not satisfied I called NGK. Person on the phone swore to me they’re both authentic solely for the fact that China isn’t allowed to manufacture any with any prefix other than “ C “. Ok lady.

 

Ride

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Could this have caused it? Ridiculous stuff I’m finding, I realize now the breather hose was crimped over instead of route under the crossmember.



Here are the backside of the valves... anything look amiss?

 

Tenman

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my valves look like I poured asphalt on them when I looked 20k miles ago. Still fires up instantly and runs fine. I’m a lugger.
 

jrusell

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In my opinion the oil in your airbox is due to running a too high oil level.
Too much oil leads to increased crankcase pressure and more oil vapors in the breather line. Eventually you end up with a situation like yours with tons of oil in the airbox.
Valves show it as well. Normal valves are nice and clean/dry. Yours being dark with slight buidup is the oil burned on the backside.

I get the impression this is a bike you bought second hand? Previous owner running too high oil level?

Doesn't look like the previous owner was very particular with maintenance. The breather hose can be a bitch some times to reconnect. Whoever had the airbox off wasn't paying close attention. Someone posted a while ago a similar situation where they pinched the hose like yours. Crankcase pressure built up and blew the valve cover seal out the side and he had a large oil leak down the right side of the engine.

Follow proper procedure to set oil level and do not run it too high. Personally when I do an oil change I dump in the recommended volume and walk away. I never worry if it is at the full line. As long as there is some on the glass after a ride it is good.
 

gapmtn1

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Sorry let me clarify :
Should these ends of the fuel line have clamps?
Yes, there is an "elbow clamp" on the fuel line at the coupling at the tank end.. Not a great representation, but it's part 24.

clamp.png

clamp2.png

clamp3.png
 
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Checkswrecks

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I doubt the breather hose was kinked so bad it was shut or you would not have oil in the airbox.
I'm seconding with what jrusell wrote in suspecting the previous owner ran the bike with too much oil. There are plenty of threads about how this can happen if people don't follow the oil change instructions and just put in oil till it shows in the viewing window. Common mistake.

Can't tell a thing about the valves with the boroscope photos because the key is the clearance at the cams under the rocker cover.
On the plus side, the kinked oil breather shows the tank was off the bike at some point and it may have been to check the valves.
BUT
There are other reasons the tank may've been lifted, including to balance the injectors which is also common.

With the condition of the plugs and air filter, you might question whether the valves were actually checked.
 

Ride

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I doubt the breather hose was kinked so bad it was shut or you would not have oil in the airbox.
I'm seconding with what jrusell wrote in suspecting the previous owner ran the bike with too much oil. There are plenty of threads about how this can happen if people don't follow the oil change instructions and just put in oil till it shows in the viewing window. Common mistake.

Can't tell a thing about the valves with the boroscope photos because the key is the clearance at the cams under the rocker cover.
On the plus side, the kinked oil breather shows the tank was off the bike at some point and it may have been to check the valves.
BUT
There are other reasons the tank may've been lifted, including to balance the injectors which is also common.

With the condition of the plugs and air filter, you might question whether the valves were actually checked.
Yeah I read about the oil site glass issue and changed it to spec based on volume. Balance the injectors? Do you mean sync the throttle bodies?
 
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