| Author | Message | ||
     Mrl |
I have a '96 S1 and I am getting oil out of what looks to be some kind of vent tube. The tube connects to the engine just under the starter and runs up beside the oil tank under the rear fairing. The oil is running down the oil tank onto the swing arm and all over my rear tire. This weekend before riding I attached a small plastic bag to catch the oil. After riding +200 miles I checked the bag and had about a half shot glass of oil in it. I looked at the service manual trying to determine what the tube was for but didn't see anything about it. Has anyone had this problem or can anyone tell me what the tube is for? | ||
| Sparky |
That tube (black rubber hose, right?) you described sounds like the trans vent hose. It should be routed in such a way that it always points upwards so that any oil fluid/ mist that gets ejected can drain back without puddling. If you can, route it along the right side frame tube with the end close to the taillight. If it's too short, it might be worthwhile to replace with a longer piece of hose. Also, don't be afraid to be creative: put a filter on the end (an old cut up athletic sock will do). Nobody will see it.  | ||
| Mrl |
I talked to a guy at my local harley shop and he also thought it was the trans vent tube. The tube is a black rubber tube and it already runs up the frame and ends just below the left turn signal. The only reason I question it being a vent tube from the trans is I am getting motor oil out of it not trans oil. My motor oil needs to be changed but I intentionally did not change it so when the bag i rigged up caught the oil I could determine if it was trans oil or motor oil and it is definitly motor oil. | ||
| Ocbueller |
If the crank seal has given up the motor oil will leak into the primary side and eventually overfill the primary. It will then escape via the trans vent. The seal is cheap, and if you're handy, not to difficult to replace. SteveH | ||
| Mrl |
Hrrmmmm The Crank seal you say. I will pull the primary cover and check the trans oil level and see if any motor oil has mixed with it. Thanks for the help!!!! | ||
| Reepicheep |
If you are just checking level, just pull the derby cover, no the whole primary cover... but thats probably what you meant... | ||
| Blake |
Mrl, Also note that you can get some expulsion, quite a lot in fact, out of the tranny vent due to vaporization (boiling off) of moisture inside the tranny/primary. Plus, I'd be very careful relying upon only an engine oil versus tranny oil diagnosis. It is not always as easy to discern the difference as one might hope. I hope it was just some moisture boiling off that caused your tranny venting issue. If so, then no worries. | ||
| Mrl |
I don't think it is just the normal venting that is happening. I have had the bike for over a year and in the last month it is dumped between about half a shot glass and a full shot glass of oil three times. What does confuse me is that it doesn't seem to happen at a constant rate. If a seal was blown I would think there would be a constant although possibly slow fluid drain. When it does happen it seems to get dumped all in a very short time and there seems to be no relation to engine temp. | ||
| Blake |
Then check the tranny lube level. If it is way high, then you've identified that it was either over-filled or that your pinion shaft seal between crankcase and primary is leaking. If the tranny lube level were high enough to cause expulsion of lube out the breather, it seems to me that you would also experiencing difficulty shifting from first into neutral when the bike is running and also a clutch that never fully disengages so that when sitting in 1st gear with the clutch lever pulled in, the running bike still wants to walk forwards a bit. Ten minutes to check the level and you'll have a very valuable data point to aid the diagnosis. | ||
| Mrl |
Blake, What are you calling the pinion shaft? The only reference to anything called the pinion in the service manual is the pinion gear which is located in the gearbox. | ||
| Blake |
The drive sprocket shaft. | ||
| Eshardball |
I am starting to see the same thing. Oil venting out of the trans breather. I found 5oz too much oil in my primary and it was no longer gold. I would not expect it to discolor quickly without the introduction of carbon from the engine oil. This happened over 600 miles since the last oil change. I bought the seal and am hoping to salvage a few more rides before digging into the primary | ||
| Zcyclone |
Mrl: I own a 01 M2, had a problem (posted Apr-May 07) regarding oil coming from the vent tube underneath the seat. I was so embarrassed on two poker runs, with this problem. Well after reading countless postings, I fixed it. The manual says use 1 qt (32 oz) in the pri/trans. DONT!!!!! Everyone here says no more than 28 oz. Well I put 26-27 oz in it. Rigged a plastic coke bottle (yes I put a hole in the top) over the tube. I've made two long trips 300 miles (each), not a drop!!! Also checked the type of fluid to put in the pri/trans. After much reading Mobil 1 V-twin won. I can tell you my bike feels like it runs smoother and quieter. Try that first before you replace any seals. |
