Gas in oil

[Fred W]

mpg sounds completely within the range of normal to me. Fuel mileage varies quite widely on normally running bikes based on operator and environment. I would not be making assumptions based on the numbers shown.

As for low miles on the bike...

How do you suppose that fuel injectors might accumulate internal deposits the most? From bikes that run a high volume of fresh fuel through them on a daily basis as they accumulate large mileages, or maybe the bikes that sit forlornly accumulating layers of dust for long(ish) periods while the odometer doesn't move a lot?

Yeah... me too.

 

[ridernotbiker]

Ok, just talking (typing?) out loud here... so help me dispell this one...

Is it possible, after some recent maintenance, the gas over fill/pressure drain (proper name?) got hung up to somewhere near the air filter box? Something like that would account for the gas smell getting past a gas rotted filter but probally not so much the amount of 'oil' volume increase.

We've had some hot and rainy days so I don't know if a combination of the tank gas expansion and rain water (or bike washes) are able to physically to do this at all.

Alrighteeee...take away my keyboard because it's hard to think outside of the box when I don't know how big the box is.

 

[FJRBluesman]

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.

Thanks again-

Jim

How much time? As others have pointed out the increase is due to not all drained back to the bottom. Most folks make the mistake of adding it to whatever mark and it's too high due to oil still draining. They check again a couple days later and its not quite high enough. They do this all over again and it appears the oil is rising.

If you've added some then later it's higher, that's normal. If each time you check it it gets higher and higher over time and even goes well above the top dot then something is strange.

I'd replace oil and and get it only to the bottom dot maybe a scoash above. Then check it each morning cold form the center stand and keep riding etc and checking and see what happens after a couple weeks.

 

[fjrjonesing]

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. ....

(snipped)

If you've added some then later it's higher, that's normal. If each time you check it it gets higher and higher over time and even goes well above the top dot then something is strange.

Bingo!

 

[escapefjrtist]

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.

Jim

More food for thought...when I change my FJRs oil and filter, I add four (4) quarts, period. This always brings the oil within the bottom 1/3 of the sight glass. Within the next week or so, the oil ends up in the mid / upper 1/3 of the glass where it stays until the next change.

Change yours using ONLY four quarts, don't keep adding extra...see what happens.

YMMV Just my $.02

Good luck.

--G

 

[jestal]

Have you checked the PCV to make sure nothing is plugged due to deposits, kinked hose, etc.... If the PCV is not actively evacuating the crankcase and pulling fresh air thru the fuel vapors normally entering the crankcase will not be removed and the fuel will condense over time. This has been the cause of "fuel in oil" in other engines in other applications many times in the past.....not necessarily on FJR's but "could happen.'

 

[Fred W]

Great suggestion.

Glad to see that you still do stop by occasionally.

As you may have noticed things have settled down around here for the most part. Not quite as much of a frat party as it was a few years back. It would be really great if you were able to come by here more often and help out in some of the stickier dilemmas.

 

[wheatonFJR]

...It would be really great if you were able to come by here more often and help out in some of the stickier dilemmas.

Oil is not sticky, it is slippery.

 

[Fred W]

He he... yeah it is. When it is good oil.

I hear Rotella Synthetic is the sticky (clutch) oil these days...

(oh boy!)

 

[bwv]

As RossKean said... Oil Analysis... $20-40.. a couple days turn around... Lab quality results.. no guessing.. no smelling... An economical and finite answer to your question.

Napa has kits that include a bottle and a mailer. Amsoil does it, you pay, they send you the stuff to send them the oil back in ~25$. There are others, maybe one close to home.

 

[FJRBluesman]

Have you checked the PCV to make sure nothing is plugged due to deposits, kinked hose, etc.... If the PCV is not actively evacuating the crankcase and pulling fresh air thru the fuel vapors normally entering the crankcase will not be removed and the fuel will condense over time. This has been the cause of "fuel in oil" in other engines in other applications many times in the past.....not necessarily on FJR's but "could happen.'

Great suggestion.
Glad to see that you still do stop by occasionally.

As you may have noticed things have settled down around here for the most part. Not quite as much of a frat party as it was a few years back. It would be really great if you were able to come by here more often and help out in some of the stickier dilemmas.

Gunny ++1K!!! on both counts! Nice to see jestal on the forum.

 

[fjrjonesing]

Have you checked the PCV to make sure nothing is plugged due to deposits, kinked hose, etc.... If the PCV is not actively evacuating the crankcase and pulling fresh air thru the fuel vapors normally entering the crankcase will not be removed and the fuel will condense over time. This has been the cause of "fuel in oil" in other engines in other applications many times in the past.....not necessarily on FJR's but "could happen.'

Thanks, Jestal. (Good to hear from you.)

Wouldn't that be great! Fact is, I was under the tank changing plugs and doing a TBS sometime prior to all this.

I'll check this weekend and report back.

Jim

 

[Fred W]

Sure, one could spend money and have the oil analyzed. And that will tell you if it is contaminated with fuel. We already know it is isn't contaminated with water or antifreeze s the oil is still clear (not milky). But after the analysis tells you it does have fuel in it, it doesn't tell you how that fuel is getting there anyway.

Not to kibosh on Jestels suggestion, but I would imagine that it would take a long time to collect and condense enough fuel vapor from bad cranckcase ventilation to raise the oil level up from the low mark to the high mark as was reported by the OP. I don't think it took all that long in his case, sounded like maybe a week's time? (that info would be helpful)

 

[FJRMGM]

you running good quality fuel with Techron through the bike and/or using Sea Foam to clean it out once in a while?

 

[bwv]

I just spent the last hour looking at my service manual, trying to look for some interface between the crankcase and the fuel delivery system.

Without considering human error or modifications to the bike... The only two places that fuel could even possibly enter the crank case, that i could see, are via the cylinders themselves (fuel past the rings), or the crankcase vent hose.

I doubt fuel is going from the throttle bodies back into the aif filter box.. espcially if the bike feels like it is running properly, and, if gas is entering the crankcase during or immediatly following a trip.... But.. this would be easy to see.. just remove the air filter and look for liquid fuel in the airbox, or a soaked air filter, right after you park it.

If there is gas mixing with the oil, to the tune of a half inch rise in level, after sitting for just a lunch break after a 200 mile ride... it has to be leaking past an injector... or more than one..., and then past the rings, without leaving enough in the cyliders to cause a starting problem or even black smoke.... I just cant see another way for it to get in there there that fast.

The condesate idea is certainly valid, but with the conditions the OP listed, i dunno if it could raise the level that quickly.

Two questions...(this goes to human error or modification)

Has there been any modification to the factory vaccuum hose setup, or to the idle air control hose setup (bypass air unit)?

Or...

Is it possible that the fuel tank vent or overflow tube was connected to the air box where the bypass air unit inlet hose would connect? This would allow for the crank vent hose entry point, via the air box... and a fuel system connection to that, via the air box... I could see negatvie pressure in the airbox maybe pulling fuel from the vent or overflow.. and then upon shutting off the bike.. the fuel draining into the crank via the breather hose...

Crazy idea?

(or Maybe the vent/overflow/bypass air hoses arent even close enough for this... I apologize, but I have not lifted the tank on my bike yet and seen this in person...that service is coming up fast though...)

 

[FJRBluesman]

Ok, let me add some confusion to this mess. BTW - All checks are done on the center stand.

I just changed my oil about 1500 miles ago. I might have slightly over filled it, just above the second set of dots. I figure for giggles I'll look at my sight glass after a few days of sitting and the oil is near the top of the sight glass. I look another time after the weekend and it's again near the top only a tiny air bubble is visible in the glass, otherwise it's all oil.

I ride to work come out after 9 hours I look at the level before leaving work and the oil is just above the upper dots. I get home and park the bike. I check it the next day (that would be this morning), the oil is halfway between the upper dots and the top of the sight glass. I ride to work again, after 9 hours I look and it's just above the upper dots. I bring it home park it for 30 minutes and check and the oil fills the entire sight glass. I just checked (10pm) it and it's very high near the top but there is a good gap of air there.

So what's with that? I don't know. I can't believe my garage floor is sloped that bad compared to work pavement. My mileage is fine. I can't believe a cup or so of fuel is draining in overnight then being burned off later. Maybe there is some way air does or doesn't get trapped near or around the sight glass and creates these weird phenomenon? I'm not really going to worry about it, I'm just going to ride.

Just thought all ya'll would like to know... or not.

 

[Donal]

Ok, let me add some confusion to this mess. BTW - All checks are done on the center stand.
I just changed my oil about 1500 miles ago. I might have slightly over filled it, just above the second set of dots. I figure for giggles I'll look at my sight glass after a few days of sitting and the oil is near the top of the sight glass. I look another time after the weekend and it's again near the top only a tiny air bubble is visible in the glass, otherwise it's all oil.

I ride to work come out after 9 hours I look at the level before leaving work and the oil is just above the upper dots. I get home and park the bike. I check it the next day (that would be this morning), the oil is halfway between the upper dots and the top of the sight glass. I ride to work again, after 9 hours I look and it's just above the upper dots. I bring it home park it for 30 minutes and check and the oil fills the entire sight glass. I just checked (10pm) it and it's very high near the top but there is a good gap of air there.

So what's with that? I don't know. I can't believe my garage floor is sloped that bad compared to work pavement. My mileage is fine. I can't believe a cup or so of fuel is draining in overnight then being burned off later. Maybe there is some way air does or doesn't get trapped near or around the sight glass and creates these weird phenomenon? I'm not really going to worry about it, I'm just going to ride.

Just thought all ya'll would like to know... or not.

If you suspect that it 'may' have something to do with the 'slope' try parking it facing the opposite way (just for giggles)..................

 

[FJRBluesman]

Ok. To follow-up on my last Post #35.

Not sure if this matter either. My driveway is sloped. I park my bike on the side stand with the left side being down hill (oil sight glass side). I open my garage door and then roll my bike in backwards, all the while it's leaning to the left side. I put it on it's center stand and walk away.

This morning the oil was right at or slightly above the upper dots, just like when I originally changed the oil. So now I'm getting consistent or inconstant readings in my garage. Go figure.

So my conclusion is there is some sort of air pocket etc that is keeping oil from settling, but overtime it does. Regardless, I don't believe there is any issue and will just continue to ride. Maybe leaning my bike to the left puts oil in a funky spot that creates the pocket for oil to stay and look too high.

There are so many documented things of the rising oil that there isn't much more explanation for it. I don't believe it's fuel, etc. I just think it's some funky design issue that was engineered into the bike and no one knew it would do this. Bummer. Lets ride!

Ride safe folks.

 

[wheatonFJR]

If it was a design issue, everybody would be complaining about it. As it is, only a distinct minority are.

 

[jcyuhn]

Seems you are seeing higher readings when the oil is hot, and lower after it has cooled? Based on some quick googling, oil expands about 4% when at 180 degrees, as opposed to room temp. Perhaps this explains some of what you are seeing.