Gas in oil

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fjrjonesing

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Magnolia, TX
Mine's an 07 that I bought last October with 9000 miles. I ride it daily and it has 16600 now. This is my 4th FJR and it runs like a top. Hate the throttle but through this entire ordeal the engine has not missed a beat.

I was on a road trip last May and noticed the oil level was higher than when I'd left. I drained a pint or so out and it smelled strongly of gasoline. Took it to a Yammie dealership where the mechanic said it was probably carbon deposits. He suggested I run a couple of cans of SeaFoam through it during my trip and watch the level. I did. The oil level continued to creep up.

Over the next 2500 miles, I changed the oil three times. While in Harrison AR, on the night before coming home, I drained it for a good 15 minutes and added oil until level was at the lower dot. Left it on the centerstand and checked it in the morning- still at the lower dot. Got on the road and watched it creep up. 200 miles down the road, I stopped for lunch. Left it on the center stand (level driveway), checked it afterwards and the sight glass was full. Changed it again and rode it home.

Left it at my local dealership when I got home. Mechanic checked compression (excellent in all cylinders) scoped the cylinders (no deposits), and checked for leaky injectors (no leaks). He changed the plugs because he said they were chalky. They weren't bad- ceramics were white. I think they're stumped. Told me to measure volumes of oil going in and drained out. I changed it about 2000 miles ago and the level is nearing the top of the window.

This has to be leaky injectors, right? And it has to be happening while the bike is not running? Suggestions appreciated...

Jim in BR

 
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When I do my oil I let it sit for 15 minutes before checking again. As RH said in the other thread you should be real close at 4.2 quarts. You can let it sit for what ever amount of time that's what's in it.

After a few days mine seems to level off and I just check it in the morning knowing it's all back down intro the pan. Never changes after that. and are you sure it's smelling like gas? When you drain it and smell it, is the oil hot (very warm what ever) or cold?

No gas should be just running into the cylinders like the old days of petcock gravity flow, it needs to be pumped out to the injectors.

 
The only way I know of for fuel to run into the cylinders is thru the injectors. If too much is pouring in form a stuck or held open injector, one cylinder should be running way rich. If that much fuel is bleeding past the rings to effect the oil level you have major issues. I don't buy the fuel is getting into the oil bit. Sorry my two cents.

 
If it ain't gas then it's antifreeze bringing up the oil level. Neither one is a very good option, but I'd take gas before antifreeze.

Or, the OP is mistaken about what/how is causing the varying oil levels. One would think that if the problem was gas getting past leaking injectors that a plug reading would show the problem. Unless a cylinder hydraulics and locks up.

 
Stop speculating and get the oil analyzed already!

As Ionbeam said, its fuel or its coolant. If the analysis shows neither, you have an overactive imagination (or are not checking oil level in a consistent (or correct) manner). There are usually other signs if antifreeze is getting into the oil - i.e. emulsion, not to mention a diminishing coolant level.

By the way, if it is either, it probably isn't going to be cheap to fix and the problem won't go away on its own.

 
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It's gas- smelled it before. Seen antifreeze in oil before, too. This ain't that. And I would think that if gas was getting past leaking injectors that a plug would be fouled (or there'd be a performance issue). None are (and there isn't). That's why I'm thinking that it has to be happening while that bike is off. (I did stop occasionally while on my trip, Fred).

Don't know how it could happen. Thought maybe one of you might know.

Thanks.

 
The "normal" way to get fuel in the oil is when an injector (or carb) is leaking. When that happens you only gain oil level while the bike is stationary, certainly not when riding it. What happens is the fuel drips into the one cylinder and seeps past the rings into the crankcase. That cylinder will have very low compression during the next cold start due to the oil seal being washed away by the gas.

Oil thinned by gas is not a good thing, in case you need to be told, but I suspect from your question that you don't. You'll want to get to the bottom of this ASAP.

One thing to be aware of on the FJR is that you will not drain all of the contaminated oil by doing an oil change. When you drain it you get 4 and a half quarts out, but there is another quart trapped in the engine that you won't get out.

 
Which of our local dealerships has the bike? GN Gonzales or Friendly? I am very curious about the outcome of this one.
I have it now, but I'd left it with Mike at Friendly for a week when I left town in June. He's worked on all my FJRs and I trust him. I'm getting ready to leave it with him again next week.

Why the curiosity?

Jim

 
We bought Dad's '07 from Friendly and I was never sorry. They have been great. I was more curious about the cause of your problems than the dealership by the way. Good luck.

 
Coolant in oil makes the oil a light brown and it'll froth like a cheap late and look like hot chocolate in color. When you drain the oil you'll see water and oil not mixing, it's obvious. Did you see these things?

If fuel is getting into your oil it is serious and should be fixed quickly. If you have a reputable dealer take'r in for a fuel/oil checkup. They should be able to do some sort of leak down check. Heck get a crashed FeeJ and grab the injectors off of it and swap'em out... although it's probably only one that's bad.

Good luck, keep us posted.

 
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Hey Jim, how much volume verses time are we talking here? FJRs are notorious for rising oil levels between changes...which is likely caused by oil being trapped and not drained with the oil change.

You indicated the oil smells of gasoline when drained. Is the oil noticeably thinner when drained? How much are you adding when performing the change?

Stuff to ponder...

--G

 
Folks, think about this. We aren't talking about massive quantities of fuel getting into the gas, just enough to cause the oil to go from low to full mark in the sight glass. How much is that? Maybe a cup (8 oz.) or so? That little amount of fuel would not be noticeable as a drop in mileage.

I can't imagine confusing coolant leakage with fuel. As mentioned, leaking coolant turns the oil milky. It doesn't take much to make the sight glass white (or coffee colored in dirty oil).

If there is fuel in the oil it could only be getting there from a leaky injector(s). Injectors will leak if they get enough deposit buildup inside. Leaky injectors will drip fuel slowly when the bike is turned off due to the residual pressure in the fuel rail. When the engine is running this would be unnoticeable as the amount of the fuel leaking is insignificant compared to the amount when the injector is intentionally open.

Assuming we are convinced that there is fuel in the oil, I would try changing the oil yet again (use 20W50 to help with the potential thinning) heavily dosing the tank with either Seafoam or Techron and go for a nice long ride, before resorting to yanking the injectors for an expensive cleaning.

PS - I've never heard that fuel diluted oil gets gritty. What is the theory behind that? Maybe that the raw gas is dissolving stuff from inside the engine? I know just mixing gas and oil outside of an engine does not make it feel gritty.

 
Thanks, everyone.

G.- this is not a one- time increase in level after an oil change. It increases over time, from the bottom dot of the sight glass to the top. As Fred said, that's not a huge volume but enough for me to worry about lost viscosity. Last change I added 4.13 qts. That got me to smack in between the dots. Usually, I add 4 qts, let it run, let it sit, then add enough of a 5th quart to bring it between the dots.

Kaitsdad- my mileage is great: 42 mpg average on my trip; 34 mpg around town.

I'm putting it back into the shop this weekend and leaving it with them for the week. Redfish, when I did that in June, my bill for the week was $125, and that included new plugs! They are not always *that* kind...

I'll let you know how it comes out.

Thanks again-

Jim

 
The MPGs sound on the low side to me, unless you have an extremely heavy throttle hand or a gigantic windshield.

Does the bike have an aftermarket fuel computer, perhaps a PC-III or PC-V? If so, I would be looking at the programing.

Since the bike has quite low miles, it would be surprising if the fool injectors were dirty. Though I suppose anything is possible.

 

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