Gas in oil - 08 WR450F

I keep getting gas in my oil after only a few hours of riding. It's not from the bowl overfilling, I've checked all that multiple times and have been turning the fuel off and running the bike til it dies lately (it would go out the overflow in the bowl anyways, not into the cylinder). So I'm thinking its from running rich at some point. Thing is, the bike seems to run perfectly. It cranks right up, never smokes, doesn't bog, it's fast as hell, etc. The only thing I see is a little soot on the outlet of the muffler. Bike is stock, other than the following:

Cut down throttle stop

Disconnected gray wire

Removed snorkel

Removed AIS

Removed muffler baffle

JD jetting kit (Red needle - 3rd clip, 168 main)

R&D fuel screw, 1-1/2 turns

o-ring mod on AP

Central MS, about 0-500 above sea level

But like I said, the bike runs great, all the time and doesn't smoke. Shouldn't it have to run REALLY rich to make its way into the oil? Is there some other reason that I'm not thinking of that would cause a strong fuel smell in the oil, soon after an oil change?

Edited by phatboy5015

Do you know if your overflow is working?

Do you know if your overflow is working?

Yes, it's working. I even drained the bowl and turned the fuel off every time I got done riding on the last 2 oil changes. Still had a strong fuel smell.

Yeah, but if the drain system is not working 100%, and your floats are set too high,  the only place for the fuel to go is inside the motor.

 

Typically that might make it harder to start though...

 

 

Are you getting 25-35 mpg?

Are you getting 25-35 mpg?

I don't really keep track of MPG. It's strictly an offroad bike. But a fill-up will last me more than a day's worth of riding (5-8 hours), without having to switch to the reserve. So that seems pretty good to me.

I don't really keep track of MPG. It's strictly an offroad bike. But a fill-up will last me more than a day's worth of riding (5-8 hours), without having to switch to the reserve. So that seems pretty good to me.

 

So how do you know when it's time to turn around and head back to the truck, if you don't track miles?

So how do you know when it's time to turn around and head back to the truck, if you don't track miles?

If the gas runs out, I switch it over to reserve and go back to the truck.

Need more info: How much more gas in relation to how may hours run time?

And how do you know you have gas in your oil?

Unless you dump all the oil, and let it sit in a nice wide open pan for a while

I cant see how you know you have gas in there? or, can I see how you know HOW MUCH gas you are getting

Are you 100% sure it is not coolant (ie, head gasket?)

 

If its less than 4 oz gas, I'd go with a float problem....ie, the fuel cock is doing its job and only letting one carb bowl full in

If its a deluge of gas I'd look at the petcock not sealing AND a float problem

 

Thats my $0.02

Need more info: How much more gas in relation to how may hours run time?

And how do you know you have gas in your oil?

Unless you dump all the oil, and let it sit in a nice wide open pan for a while

I cant see how you know you have gas in there? or, can I see how you know HOW MUCH gas you are getting

Are you 100% sure it is not coolant (ie, head gasket?)

If its less than 4 oz gas, I'd go with a float problem....ie, the fuel cock is doing its job and only letting one carb bowl full in

If its a deluge of gas I'd look at the petcock not sealing AND a float problem

Thats my $0.02

It's not coolant because it smells like gas... Coolant doesn't smell like gas. And if the fuel shutoff valve is working, then even if the bowl is full, it will just stay full. If no more gas can come in because the valve is off, then it won't overflow. But like I said, even after draining the bowl every time I got done riding, it still has a fuel smell.

But the next time I change the oil, I guess it wouldn't be a bad idea to just let it sit overnight with the drain plugs out, just in case there's any residual fuel that's just staying in there when I change the oil.

Edited by phatboy5015

I think someone is pouring gas into your crankcase.

Ok, I just removed the carb from the bike and it's all working like it's supposed to. Floats are shutting off gas when bowl is full and overflow tube is clear and working correctly. So I'm back to square one..

Also, AP sprays for 1 second, so I'm pretty sure that's not causing a problem either.

Edited by phatboy5015

Just took the bike for a test ride after putting it all back together. I didn't change anything, but now I have the dreaded off idle bog.. :-(

The only thing I can figure is maybe the fuel screw o-ring got screwed up when I pulled it out and put it back in. Another weird thing is that if I pull the hot start and rev it, there's no bog, which I assume means it's running rich.. It also seemed to run a better with the fuel screw turned all the way in??

Get a fuel injected wr ;)

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now