Bike not wanting to start, oil leaking out the airbox..help!

Bike info: 1982 Seca XJ750
Hi everyone, my bike has been sitting undercover for the last few months. Before I put her down for the winter, I tipped her over on accident which I think is the root of my problems. When I went to start my bike for the first time it would rev and sound like it wanted to start but would just not fire. Then I noticed that when I would try to start the bike and pull the throttle, oil started leaking out of what I believe to be the airbox. I did the smell test to my oil and it definitely smells of gasoline. That was all about two weeks ago. Yesterday I decided to go try it again. After I hooked my bike up to my car via jumper cables and did some hard reving I got it started and was ecstatic until I looked down and noticed the oil spraying from my bike so I shut her down(I think it was going to die anyway), I think it was coming out the airbox again. Now I need to know what I need to do to get my bike up and running again before the weather gets any nicer! I am not very mechanically inclined but if I can save some money by doing it myself(and probably with the help of my dads friend) then I am willing to try. Any input would be greatly appreciated. Thanks!

P.S.
Where do you spray insta-start?

 

If your oil smells like gas, you have to change it. More than likely, you had a float stick dumping gas into the crankcase. This overfilled the crankcase and thus let to the oil in the airbox.

So, before you change the oil, make sure your floats are unstuck. Let us know if you need help with that or you know the drill. You definitely don't want to be running the bike until you resolve the probable float problem and change the oil.

 

Sounds like your carbs need to come off for cleaning / rebuild. Check out the threads from chacal about "in the house of clean"

 

Re: Bike not wanting to start, oil leaking out the airbox..h

Joe- I have no idea what "floats" are or how to unstick em. Can you help me out with that?

 

"Floats" are literally that, small floats inside each carburetor that shut off (or aren't as in your case) fuel to the carb once the float bowl is full. They work the same way a float in a toilet works to shut off incomng water once it's full. If they stick, AND your petcock has a problem or is on PRI, this can happen. One or more float is not doing its job, but it should not be able to have enough fuel to fill up the motor unless there is also a fuel shutoff problem "upstream."

Floats CAN sometimes be unstuck by rapping on the float bowls with a screwdriver handle, however it is more likely a piece of crud has become lodged and no amount of tapping will fix that.

You also need to figure out why your petcock hasn't been shutting off the fuel supply. Take the opportunity to install an inline fuel filter, I suspect you don't have one and that may also be part of the cause. (Crud infiltration.)

And as mentioned above, don't run the motor without new oil but fix this issue first.

 

Dropping the bike can cause the floats to stick.
As Fitz said there's something wrong with your petcock that it let fuel flow with the bike off, unless you left it on prime.
Gas has filled your crankcase that's why oil is blowing out the breather tube into your airbox.

 

Re: Bike not wanting to start, oil leaking out the airbox..h

I did leave it on PRI for a period of time, does it matter if the bike was running or not?

 

Is this going to be something I can fix myself? If I took it into a shop, what do you think I might pay??

 

In general I usually recommend AGAINST taking these bikes to a mechanic... Around here at least, if a mechanic will even touch the machine, they won't do a very good job, and will charge you an arm, leg, and your first born for it.

If you left the bike on PRI, then yes, that could be one of the causes of your flooded crankcase. The petcock on our bikes is vacuum driven when left in the "on" position (assuming the petcock works properly, also), so that it doesn't allow fuel to flow when the bike isn't running. When left on prime, gravity will feed as much fuel as the carbs will allow, and if your floats stick open (which can happen if the bike gets dropped, as TheHound pointed out) it'll juts drain your gas tank into your oil.

Sometimes you can get your floats to un-stick with a firm rap from a screwdriver handle or the like on the back of each float bowl. In my case, when my floats stuck open, that didn't work. I had to dis-assemble my carbs and clean them again, junk from the tank had found its way into my carbs and was wedging my float valves open so that they could not close and shut off fuel flow. Couple that with a petcock that isn't working properly and bad things can happen in a hurry.

 

Re: Bike not wanting to start, oil leaking out the airbox..h

Well I rebuilt my petcock last year so I don't think there is a problem with that. Suppose that the only reason my bike is having these problems is because I tipped it over and I left it on Prime. What steps should I follow to get my bike running again? Just an oil change and possibly change the air filter? Would that fix my problems?

 

It could, thats where I would start. Fresh oil, fresh air filter, double check that your plugs arent fouled, clean them up a bit if they look salvageable, or replace if not. Try to crank her up and see how she does.

 

Based on your story, yes it seems like tipping your bike and leaving the petcock on prime allowed your crank case to fill with fuel. Tap the float bowls with a rubber mallet to try to seat the float needle valves. Change the oil and filter. Don't use "PRIME" except to fill your carbs when they're totally empty. Use "ON" and "RESERVE" the rest of the time.

After you change your oil, check it a day or so later. Make sure the level is the same, and that the oil doesn't smell like fuel.

Don't run the engine with fuel in the oil. The oil has lost it's viscosity and lubricting properties. It's nearly as bad as running your engine dry.

 

Re: Bike not wanting to start, oil leaking out the airbox..h

dont take it to a shop!! the shops around here want to charge over 400 bucks to clean and adjust the carbs! not to mention the petcock problems

 

I just changed the oil and cleaned the air filter out today, I tried to start it, and again it revs but doesn't fire. What should I do now? I think I will order a replacement air filter, could that cause my bike not to start? Also where do I spray insta-start? Could I get a picture or can someone describe where I am suppose to spray it? Any other suggestions for things to try next? I was gonna pull the plugs and check them but I didn't have the right tool, what tool do I need to get those out?

 

P.S.
My Bike is no longer leaking, changing the oil and cleaning out the air filter fixed that problem.

 

Anyone?? I could really use some help!

 

first off, check to make sure you have spark all your plugs. pull of one at a time, crank the engine while holding the tip of the plug to the engine and see if there is a spark. use the engine bolts as theyre steel. Make sure the plugs arent fouled as well. This probably isnt your problem but you want to be sure. From your post it sounds like you need to pull your carbs and clean them. Search the forums for instructions on how to do this. Its a duanting task at first, but after a couple times doing it youll be able to disasemble/reasemble from memory in an hour.