Gas in oil?

[Chrisf]

This is very strange. A week ago I started my GS1000. It had been sitting outside, so fairly cold. It started fairly easily, however after running for 10 minutes I noticed that there seemed to be a lot of gas coming out from the carburetors, spilling onto the engine case. I had never had that before and shut it off. Later that evening I started it and pulled it into the garage to get ready to do some winter service on it. Today I started it to warm it up to drain the oil. It seemed to run normally. When I pulled the oil plug what came out was not just oil. It was very diluted and it came out like water out of the end of the hose, pretty high pressure. I pulled the oil filter and it did the same thing.

1. Has anyone ever seen this before?

2. It has been sitting outside uncovered for the last month or so. Is it more likely to be water from a bad gasket? No drips under the bike while sitting.

3. Could it be gasoline?

At this point I'm trying to decide if I need to do more to the engine that I really wanted to.

Thanks in advance.

Chris

[Steve]

You are the only one close enough to sniff it to see if it smells like gasoline.

Sounds you you have a petcock that is not sealing (do you have it in the correct position?) and also a carb inlet valve that is not sealing.

One other possibility is that the vacuum diaphragm in the petcock has failed and is sending gas down the hose to #2 carb, which then floods the crankcase.

.

[Hinermad]

My Triumph did that when I forgot to turn off the petcock. (It didn't have a vacuum operated petcock like GSes have.) Fuel would flow past the needle valves in the carbs, overflow the bowls, and end up filling the airbox and cylinders. (It didn't help that the local insect life would build mud nests in the bowl overflow hoses, clogging them.) Gas would eventually end up draining into the oil pan, contaminating the oil.

I don't know for sure that what you're seeing is gas (although the smell should give it away) but I'm not sure how significant amounts of water would get into your oil pan unless you left the oil fill plug off. Plus water wouldn't dilute the oil like gas would; oil and water separate. Could you see signs of two separate liquids when you drained it?

But a petcock that isn't shutting off when the engine is off, and one or more needle valves leaking or stuck open is where I'd start looking.

[Carter Turk]

Likely gas in the crankcase.
Either sticking float needle in carbs or bad petcock diaphram.
I picked up a $100 Honda CBR 600F2 that I've been fussing with.
Guy sold it due to broken cam cover bolt that needed to be extracted.
Had some other minor issues with it, but it fired up and I rode it on a few short blips.
Last time I walked into garage a strong smell of gas was present.
Took the exhaust can off the bike and peered in with a flash light, totally full of raw gas.
I syringed out all that I could and ordered a cheap petcock replacement.
The original petcock flowed in the ON or Reserve position, whick it's not supposed to do.
Drained oil, changed filter, new oil, installed new petcock.
Fired right up, went on a 25 mile blip, all was well.
Suppose I could of flushed new oil out immediately, but figured an oil change was enough.

[Downs]

If you were overflowing the carbs you probably overflowed into the cylinders as well. The rings don't make a perfect seal especially when not under compression so gas will leak past them into the crankcase. This was a recurring problem on my GS1000 and on a Suzuki Bandit 1200. I "fixed" it on the GS1000 with a combination of replacing the needle float valves and seats and throwing the crappy Suzuki petcock in the garbage and replacing with a Pingel manual valve. I've never had an "Automatic" petcock work worth a damn. I stick with the manual ones.

[Chrisf]

Thanks everyone. You all confirmed a thought that I had just a few minutes ago. I drained it directly into a closed pan, but with how diluted it was I agree that it was gas and not water. The garage does have a strong gasoline smell right now and the only thing that could be causing it is the oil/gas solution.

I had accidentally left the petcock on prime for a couple of days leading up to my restart. This is when the gas started flowing. I have rebuild kits for the carbs that I was planning on installing, and I'll probably order a petcock rebuild kit as well. I'm trying to do as much maintenance now so it is ready for some great riding.

Would you doing any kind "flush" with oil, i.e. fill it, run it, drain it? I just don't want it to cause any significant issues.

On another note, and this should probably be a thread in itself. I'm going to replace clutch springs while I have the oil drained, and plates if needed. Has anyone ever been able to clean the oil level viewing glass? Mine is very dark and I can't see a level at all. Is there anything that could clean it without ruining the seal?

[gsrick]

If you've drain the oil/gas, you should change your oil filter. If you are doing the clutch, just let what is left in the engine, which should be very minimal, air out. The fuel residue in the engine should evaporate by itself. A fan directed into the clutch area while it's open will speed thing up. Soak the new clutch friction discs in a ziplock baggie with oil. It doesn't take much oil it you use a straw and suck out as much air as possible and let it set for an hour or two.

[cowboyup3371]

You do not want or need those carb rebuild kits as they don't have everything you need and you don't need the jets inside of them. Yes it was a waste of money but you will be better served, and will spend less money in the end, just getting your orings from www.cycleorings.com (owner is a member here) and maybe using just the bowl gaskets from the kits. Then go here, http://members.dslextreme.com/users/bikecliff, and click on the carb rebuild tutorial. Please follow it to the letter or you'll be doing the job again in the near future

[Hinermad]

I had accidentally left the petcock on prime for a couple of days leading up to my restart. This is when the gas started flowing. I have rebuild kits for the carbs that I was planning on installing, and I'll probably order a petcock rebuild kit as well. I'm trying to do as much maintenance now so it is ready for some great riding.

Leaving the petcock on "prime" would be enough to cause your problem. (That's the same as leaving it "on" with my Triumph.) Unless your GS petcock is leaking fuel when it's set to "on" or "reserve" with the engine not running, it shouldn't need to be rebuilt. (Although many people prefer to replace it with a non-vacuum operated one for reliability reasons.)

As others have said, you don't really need to use all the parts in your carb rebuild kits. If the bike already runs, a good cleaning and new o-rings will cover a multitude of issues.

[hannibal]

The usual advice on the clutch is to replace the springs with OEM springs (not aftermarket HD springs). This usually fixes the problem assuming it's currently slipping.