New fuel leak, not riding now, how dangerous? '80 GS850 G

[GregM.]

Hi, Thanks for this terriffic site... AND all you experts that so generously type out advice. I've been out of motorcycling for a very long time, but now I'm getting back into it. Also, I am NOT a very knowledgable mechanic, so I'm sorry for the rookie-ish questions.

I bought my '80 GS850G (21K mi.) from a local Seattle guy here a few months ago... all original and stock as far as I've been able to research so far. I don't know how many owners it's had (this guy only owned it 3 years, and he didn't seem to know a lot about it) but still, with the help of a knowledgeable friend it checked out very good. It started, idled and ran great, smooth, strong, no flat spots or concerns. It's probably been garaged its whole life as it's really clean and ship-shape.

To start with a good baseline, we immediately changed all the fluids, filters and battery. I washed and waxed it and put a new Metzler on the front (to coordinate with the good one on the rear) , and for 2 months of very parttime riding it's been great!! And I'm loving it, just perfect for me, and from an era of the bikes that I was the most familiar with.

So, my new problem that just started, and yes, I'm assuming it needs to be fixed before I go on. My bike HAD been quite clean, just some slow seepage - oil, I think - around the cylinders (my friend said, no big concern, many of these old inline fours do that). And I'd told him that nothing was leaking on the ground, fine.

But in retrospect, that wasn't totally 100% true, I had been getting a very MINOR leak of something in the last month. It just didn't concern me, all that happened was occasionally when I would kick up the sidestand there would be a light brown stain on the garage floor where the sidestand had been set. But there was no smell or odor, and again it was just a stain, so I wasn't concerned. Also, a guy told me he thought I might have an oil leak out of the cam chain tensioner... and maybe another small one out of the tach cable? ... Anyway.

Now the events of the last few weeks - I don't know if these are related - I'm just trying to paint a complete picture. I did quite a bit of stop and go riding a few weeks ago - commuting kind of stuff, lots of errand running and some fun, 45 mile, higher speed juants. All this was in hot (for Seattle, 85 degrees) weather. Near the end of this fun week, somebody reminded me to check the oil level. I hadn't been too concened about this, because as I said I'd put in all new oil etc. 2 1/2 months ago... I'd only done, maybe 1500 miles since then... and I didn't have any major oil leak. But, Oopps, I was low, put in 1 1/2 qt. Crap! I felt horrible... where'd it go? Maybe I'm blowing a bunch of smoke out the exhaust pipes, I hadn't noticed anything... Crap - Crap - Crap!!

Anyway, around this same time, maybe just after... during a fuel fill-up, I added some Chevron Fuel Conditioner (I think that was the brand, not 100% sure) that the previous owner had given me - he said he thought it was a good idea to add this once in a while. I followed the directions and thought now would be a good time since it had been 2 or 3 months since the last time, and it was during this active riding time.

My fun riding continued up till a week ago, and by the way, still running good as ever, but now I've stopped. Twice in the last 2 weeks I've noticed a strong gas smell in the garage. After the first time (no leaks on the floor and none that jumped out at me on the bike - remember I'm new at knowing where and what to look for) I just kept on going. I thought, my oil level is still OK, it's still running great... and the smell went away. Normal riding continued.

Then it happened again. The strong smell I mean. And this time I'd had the bike on the center stand. This time there was a puddle on the garage floor - maybe 6" diameter, light brown, seemed kind of oily, but smelled like gas. I found a small puddle of it on the right side of the engine - there's a concave indentation, a part of the engine case up above the oil check window... I also found it, I think, on the carb side of the airbox. Hard to really pinpoint it, the whole engine area is kind of messy now, not nearly as clean as when I detailed it 2 1/2 months ago.

Help please. I've been reading this site on and off since I got my bike, and now in the last week, since the fuel leak and smell, I've done more and I "searched" and looked in Old Q&A and it looks like I might have a fuel petcock or a carb problem.

Any advice or trouble shooting would be very helpful. I've never even taken off a fuel tank before, so all this is quite new to me. I've read the carb cleaning section...Whew! Whatever real work I need to have done, will probably be done by a professional... However I'm looking for as much info as possible, a progression of things to check out... and of course anything that I feel comfortable doing, I certainly will. I don't mind getting my hands dirty... I just don't want to screw anything up and as I said I have limited knowledge, tools and time... and I want to get back to riding.

Thanks for all the advice you all can give me... all little tid-bits will help educate me and I really appreciate it. Greg

P.S. Thinking positive thoughts for all down where "Katrina" hit. Devasting and horrible.

[maparker]

Not sure if your petcock is the same as some of these others but if it is instead of being the on/off like I was used to from dirt bikes mine has a 3-position petcock: On (usually straight down) Res and Pri. Before finding this site I thought it was on (open all the time maybe?) Primary and Reserve. Boy was I wrong. Turns out that these are vacuum operated and stand for On, Reserve and PRIME! The Pri setting lets gas flow freely from the tank into the carbs by gravity. If you have left it in this position and parked the bike gas will fill the carbs, leak and sometimes also fill up your airbox and crankcase!

First check your petcock, even if its not in the Pri position it could still be the culprit. Second check your airbox for gas and MOST IMPORTANTLY check your oil. If there is oil in the gas CHANGE IT. Gas in the crankcase = Bad Things!

Even if you didn't leave it in prime your petcock could still be failing and letting gas into the carbs. Do a search of the forum, lots of good info on how to check/rebuild.

You may also have a float stuck on a carb, sometimes this can cause similar leaks by allowing the float bowls to overfill and leak. Try tapping the sides of your carbs with the handle of a screw driver, sometimes this will break it lose.

Anyone else with suggestions?

Good luck,
Mark

[SqDancerLynn1]

Change the OIL too it may have gas in it !!!!!

[GregM.]

Thanks for the two suggetions... Mark that's a lot of great info.

And yes I have learned what kind of petcock is on my 850... it's the one you describe : On, Res and Pri... and it is in the On position. However, I have swiched it to both Res and Pri in recent weeks. The Res worked as it supposed to... later filled up and then put it back to On. I moved it to Pri, just to move the switch around... trying to make sure everything works on my new "old" bike.

So I hear you ... could still be the petcock, or stuck float in the carb. Any other tips or help regarding this.
BTW is there a way to check if gas has gotten in to the oil?? Is smell the only way?? And, yes, I'll keep matches away

Another tid-bit... After the last time it happened, I did quite a bit of cleanig up with rags..... and then finally it stopped... that's been a number of days... it's now on the sidestand... there is no more leaking or smell of gas at this time. Does the fact that this seemed to come out of nowhere, but then is only happening intermittently significant?? And now, it's just sitting there fine as can be?? All ideas are very educating to me..

Thanks again, Greg