426 fuel in the oil after flooding the carb?

8 replies to this topic
  • vonkaiser2001

Posted March 10, 2013 - 06:24 PM


Hey guys. I'm a proud owner of my first four stroke bike. I bought an '01 yzf426 a few nights ago. The guy I bought it from did a fairly lousy job explaining the starting procedures to me and after I got it home and off the truck I did a world class job of flooding the hell out of it and fouling the plug. Well needless to say I had to tear it down a bit and cleaned the carb and put in a new CR8EK plug and finally got it started. After watching several YouTube videos over and over that is. The problem now is that when I rode it for the first time today and finally parked it after an hour, I was getting a puddle of yellowish milky oil from the breather hose that goes from the cam cover on top of the engine. The bike ran amazingly strong by the way with no indication of any issues.

Is it possible that fuel made its way past the rings and mixed with the oil since I had flooded it so badly? The oil on the dipstick now has a yellowish green tint and smells like straight gasoline. If so could I get away with just changing the oil and keeping an eye on it? I'm positive the top end is new with an hour on it when I bought it so I don't wanna start tearing it apart to replace a head gasket that may not be bad. I'm hoping to chalk it up to my own stupidity when I screwed up the starting procedures. Thanks for any help guys!!!!

  • etuke

Posted March 10, 2013 - 07:07 PM


change the oil,I did the same thing when I bought the 426.I hauled it to the pit and spent a full hour trying to start it,luckily there was a guy there that was riding a 426 and he got it started in 3 kicks.My biggest problem starting it was being so used to the 2 stroke bike I always twisted the throttle while kicking.Of course this floods the 4 stroke with the accelerator pump,I quickly learned to put my throttle hand on the cables instead of the twister when kicking and haven't had a problem since.You still have to use the proper technique but once it all done properly the bike is actually very easy to start,even when hot.Keep a check on the antifreeze just to be sure.

Edited by etuke, March 10, 2013 - 07:12 PM.

  • vonkaiser2001

Posted March 11, 2013 - 06:02 AM


Awesome. I'm really glad to have at least some type of confirmation that this has happened to someone else. I was really worried that I was gonna have to do engine work before I'd even owned it for a week. I will go to the dealer today and buy all the new fluids and filter and change it tonight and update the outcome. The good news is I learned the starting procedures after flooding it and fouling the plug and it started like a dream all day in the woods here in PA. I went from dreading the thought of kicking it to realizing what a piece of cake it is as long as u follow the procedure. First or second kick every time. My right foot is seriously bruised from kicking for an hour unsuccessfully that first night!! Hoping that's the only hard lesson I have to learn from my ignorance of this new machine and it really is just gasoline in the oil. The bike is an animal so far otherwise and even with the uncertainty of things as I drove home from my first day of riding the smile on my face was apparent. Thanks for the advice and I'll be proud to share all the tricks I learn as I go as well!!

Jeff B.
Pittsburgh, PA

  • vonkaiser2001

Posted March 11, 2013 - 06:07 AM


And by the way some of the best advice I could give is definitely hold the master cylinder and not the throttle when kicking!! The result otherwise is this mess under the engine!!

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  • grayracer513

Posted March 11, 2013 - 06:50 AM


Gasoline will not make the oil yellow and/or milky. It only makes it thinner and gives it a gas smell. Milky, foamy, yellow-white stuff in the oil is usually water or coolant. Seeing this in the breather isn't so bad. It could simply be condensation from air moving up into the tube as it cools. But if the engine oil itself looks like that, it's not good.

  • vonkaiser2001

Posted March 11, 2013 - 09:56 AM


Actually the engine oil on the dipstick does not look like that. But it does smell very strongly of gasoline. Don't know if that's an indicator of anything in particular or not.

  • vonkaiser2001

Posted March 11, 2013 - 10:06 AM


Grayracer. Thanks very much for the input on my topic. I'm new here but have been burning up my iPad battery on TT since I bought my bike and notice you seem to be very helpful and well respected on many if the different threads. My question is, if I have water or condensation in the oil and it's spitting the filmy stuff out of the breather, would an oil change (goes without saying) with any type of additive to remove moisture be advised? I really don't want to tear it down to the head gasket without at least running some clean oil for a short time and keeping an eye on my coolant level. Would this be a bad idea? I realize I don't want to overheat the bike and warp the head but yet don't want to damage anything else.

  • grayracer513

Posted March 11, 2013 - 12:47 PM


There is probably no moisture in the oil, only the breather, but there might be. As you do your oil change, watch the first few drops out of the plug. Let the oil flow out slowly from the loose plug while you watch it. Any water or coolant will be the first stuff at the bottom of the oil. If the oil doesn't look milky, don't worry about it other than to keep your eye on the fluid levels as is normally prudent. If it IS contaminated, then you need to be careful and watch things closely as you first run it up afterward.

The gas smell is just about gas. If you get the engine up to normal temperatures and run it for half an hour, that should be gone.

  • vonkaiser2001

Posted March 11, 2013 - 01:19 PM


Ok I'll do that. Do you think it's a good idea to start the bike and let it warm up for a few minutes before I do the change? I've read on here that shutting the engine down without getting it fully hot can foul the plug. What do YOU think?

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