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Moderate Oil Leak

8202 Views 23 Replies 6 Participants Last post by  lizrdbrth
I bought this bike a little over a month ago and have been riding it regularly since. I noticed that it had a small oil leak when I got it but the guy I bought it from said that it was less severe than it actually looks. I don't know anything about motorcycles as I chose this one as my first motorcycle. I come here for help because I think maybe someone here can identify this. Maybe someone has had the same issue before. It's a 2005 model and as far as I can tell is totally stock. My brother went to school for engines and he told me from looking at it, that he thinks the leak is coming from where the front sprocket goes into the engine? If that is so then why is the head and everything below it soaked with oil. The plug, chain, and chain-guard is soaked with oil, as well as the plate that is on the bottom of the engine is holding oil and drips. It is slinging oil back onto the tire a little and I am afraid it's going to cause me an accident. Please take a look at these pictures and tell me if you think that it is going to be worth getting it fixed. I have an appointment scheduled to get it looked at by World of Yamaha but it's not until the 20th. If it's not going to be worth it to fix it (money) then I'm not going to get it fixed. I only paid $700 for it and the guy I bought it from doesn't know anything about bikes either, so I think I got a good deal. It runs good and I haven't had any problems out of it except for this and the gear will sometimes slip from 5th down if I'm really giving it hell.

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I pressure washed it and left it running. Found out exactly where it's leaking but I have no idea what it is.

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Actually I think I found out where it is. See the hole in the red box I outlined? Are there supposed to be screws in that one and the one to the right of it (not in the picture). If so then I think I may have found how to fix it? It seems that under that thing that I have labeled UNDER HERE it's not all the way together, and may be leaking there, since the chain and chain-guard is soaked in oil.

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Dood, your bike gots issues

Mostly curable, but you'll need to identify some things..

If you have oil in your airbox it shouldn't be there. That little piece of tubing with the flattened end is the drain. Put something under it, pull the tube and drain it. If it smells like gas you have a stuck float. If it doesn't, some dink over-oiled the air filter, layed the bike down for a prolonged period, or it has so much blowby that it's filling the airbox. If it's anything other than an overoiled filter you need to stop dead in your tracks and get some advice.

I loosened the airbox cover and oil poured out of it so I put it back on.

edit: Ok I took it completely off and this is what happened. I don't have a 10mm so I can't take the seat off to find out how to take the airbox off and find out why it's leaking so bad.

It appears a moderate oil leak turned into a major oil leak.
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You don't need to remove the seat. Oil shouldn't be there and none of the potential causes are under the seat.

Drain the airbox, scrub that motor clean and get some proper tools and we can talk you through each of the issues if you're willing to try. Otherwise wait for that appointment at the dealer and don't start the bike.

Can you see the oil level in the window or is the entire thing dark?

The whole thing is dark most of the time. Right now it's dark. You know actually the dirt I think is rusted onto the motor... I don't know how to clean that off. Also I would rather get it done myself than take it to the dealer. I really appreciate any help anyone can give.
Your crank case is most likely overfilled with gas and oil mixture due to a stuck float. The engine leaks are likely a seperate issue, but not being helped any by the overfilling.

Drain the airbox first. Do NOT try to run the bike. Since your crank case is already full of stuff that shouldn't be there we're gunna leave it that way for now.

Make sure there's a full tank. Pull the gas line loose at the carb with the petcock in the "off" position. Is there gas running out of the end of the hose?

Next, drain the airbox. Put the petcock in the "on" position and leave the bike overnight. Check the airbox for oil the next day and report back.

If there's gas or oil in the airbox overnight you have a stuck float or crud in the float bowl. Relatively easy fix and once corrected you can drain the crankcase, refill with oil and hopefully save the motor.

One step at a time.

How do I drain the airbox? I have already taken the airbox cover off. The bike runs fine it's just leaking oil. It's still leaking oil from under the airbox behind the screen. I will turn off the petcock and pull the gas line loose while I wait for your response. How do I even check the airbox? I can't see in it past the screen.

edit: There was only a little gas coming out then it stopped. There is a full tank of gas and it still has gas in it. I don't know how to get past the screen of the airbox. Though there is no more oil coming out the side.
You don't need to check the airbox by opening it up. There's a drain. You can see it in your pic of the screw, the one with your little red "square" outlining the leak. Just to the right of the square you'll see a short piece of vinyl tubing, flattened on the south end. Pull it off. Yours is brown cuz it's full of oil. It's supposed to be clear.

Whether it runs fine or not, the crank case is full of gas and oil. If you continue to run the bike with it in the crank case your motor will be permanently and irreversably turned into a paperweight. If you simply drain the crankcase and refill it with oil and continue riding the bike without fixing the carb you'll only delay the exposion by one day. Trust me.

Ok I put the gas hose back on and turned the petcock to the ON position, and the airbox is draining, slowly.
I just checked it and it had been leaking out of the side of the airbox still, and when I pulled the drain off several drops of oil started leaking out of it.
Ok. Now read the carb thread and if you feel confident enough to remove and clean the carb and set the float you'll be back in buisiness.

Drain the oil. Lean the bike over from side-to-side several times to get as much oil/gas out of the crank case as possible. You may want to let it rest on the kickstand with the drain plug removed overnight and allow the gas to evaporate. Remove the vent line from the airbox to aid in evaporation, drain the airbox again and clean and re-oil the air cleaner.

Refill the crank case with cheap oil. Once your carb is fixed, run the bike for 15 or 20 minutes, drain the oil again, clean both filters and refill. I'd recomend repeating the process at least one more time.

Then you can tackle the oil leaks, which may diminish greatly once the overfilling has stopped.

Do yourself a favor and scrub that bike squeaky clean before you start, paricularly the engine and carb.

I will do this. Thanks for all the help. Do you have any suggestions on scrubbing the engine and carb? Like what should I use? It's really dirty and I think the dirt is actually rusted onto the engine from the person that had it before me letting it sit for so long.
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