| Author | Message | |||
     Captainkirk |
Figures.... Get a RARE day in March when I can ride and something goes wrong. OK, here goes... '99M2. Rode to work today, about 2 miles or so. When I was ready to leave, I noticed a small drop of oil under the kickstand. Figuring it was blowback from my leaky rocker box gasket (yeah, I know. I'm gonna change them REAL soon) I wasn't too worried. Rode home and went to wipe the bike down and there's another drip. Looking up I see a streak of oil down the side of the oil tank, pull the seat, and find oil on the top of the tank around the dipstick cap, which was in snug,BTW.So I'm looking at the top of this tank trying to figure out WTH is leaking, and see what appears to be cracks in the tank around the vent fitting. How this would crack is beyond me. So I start thinking...(bad move!) I start the bike with the cap off. I see oil recirculating with foamy air bubbles in it, which I guess makes sense, but what freaks me out is the oil level, which I try to keep on the high side of the dipstick mark anyway, starts rising. And it keeps rising...all the way to the bottom of the filler neck, at which point I shut 'er down. Now I start thinking again (d'oh!) What if the oil tank over pressurized and popped at the vent fitting? So, in order to avoid any other hazardous thinking, I pose the following questions to those who might know... 1) Am I running my oil level too high? Even though I'm running HD20W50 it was almost 60 today. 2) Am I correct in interpreting the service manual to show the vent line exiting into the cam cover? Is this an open line, or is there a fitting on it? (That could be clogged) No, I didn't yet disconnect the line and try to blow thru it. 3) Is it normal, as I assumed, for the return oil to be full of bubbles? And is it normal for the tank level to rise up to the filler neck like it did? If not, WTH is going on? 4) Anybody else (esp. dealer/mechanics) ever see or hear of this before? This is the first time I've ever seen anything other than a light film anywhere around the oil tank. 5) If I'm correct, and the tank IS cracked, has anybody ever tried to repair one (bear in mind we're talking about the very top, around the vent line fitting hole) using 2 part epoxy or JB weld or the like, or am I wasting my time? And if I am right about the pressurization, what could have caused it? The line appears unkinked and straight as far down as I can visually follow it. Talk to me. The last thing I want to do is tear into my bike at the onset of riding weather, but I guess better now than later!  | |||
| Cyclonemick |
Oil level rises as it heats up that's why you should always check it at normal riding temps. And that's why it rose on you when you had the cap off. I try to keep my oil level right in the middle of the stick or maybe just a tad bit low and if you check it regularly you should have no problem. As for the crack someone else should chime in any moment now. | |||
| Andys |
Captain, Sounds like you have too much oil in the motor. These motors are funny. Actually the oil tanks are. There is supposed to be a anti-drain valve of some sort in the oil lines to keep the oil in the tank when the bike is turned off, but this rarely works. Since the tanks are located high above the motor gravity allows oil to run down into the motor. They call this "sumping." So how does this increase oil levels? Keep in mind we are draining the oil tank and not the motor, so if we wait too long (like overnight) there's a good possiblity that a bunch of oil is now sitting at the bottom of the motor instead of sitting in the tank. When we drain the tank, change the oil filter and then put 2 quarts of the gold stuff back in the tank we actually end up with too much oil because we didn't remove the oil from the bottom of the motor. So when we start the motor up the oil pump scavanges the oil out of the sump, adds it to the oil already in the tank and now we have an overflow condition. The trick to not having the overfill problem is to drain the tank within minutes of returning home from a ride. At that time the motor will be fully scavanged, you'll drain all the oil out and your overfill situation will be gone. To resolve your current situation you could simply drain some of the oil out until it reads only halfway up the dipstick (I keep my oil level reading at halfway or lower on the dipstick) or you could take the bike for a nice hard ride (running throught he rev range) to make sure all the oil has been scavanged out of the motor, then immediately dump the oil as soon as you get home. Add two quarts of your favorite stuff and you're ready to go (the amount left in the filter is not significant enough--I actually run the long Dyna filter with the same 2 quarts of oil--never a problem). Note 1: the seat is designed to hold the dipstick in under high pressure situations. Note 2: Sportsters don't have this problem because their oil tank is located below the motor and therefore isn't affected by gravity. Note 3: only reason I know this so well, is that I had to clean up about a quart and half of Mobil 1 off my rear brake after chasing Court at high speed through the hills and dales of WI one summer. So I asked the resident engineer at Buell what was up. | |||
| Imonabuss |
Andys, Very nice description...only inaccuracy is regarding the Sportster...their oil tank is also above the motor, and they have the same problem. Note that the XB series has the oil tank much lower, which reduces the issue, but it still can exist. You don't really have to take the bike for a hard ride, just always start up your motor and warm it up for a bit before shutting it off and checking the oil. | |||
| Spiderman |
Remember there is a little allen screw under the motor so you can drain the sump. I do this when I put MJ up for storage to make sure I get all the bad oil out | |||
| Bomber |
Spidey . . .. can you be a bit more specific about the location of said screw? | |||
| Spiderman |
under the motor there is basically a block, that is the small sump that the motor has, where the windage tray is bassically. It is tword the back of the motor, you will want to put the bike on a rear stand an get under there to find it. It is resesed so if the bottom of your motor is gunky you will not be able to see it. I'll try an post a pic tonight. | |||
| Spiderman |
TO the left is the rear of the motor, the best way to find it is that little half circle. | |||
| M1combat |
Do the XB's have this? | |||
| Spiderman |
Yep, You will have to remove the muffler of course. That pic is off a 04 Sporty, I checked the XB's an they have it too. | |||
| Bomber |
Spidey . . .thanks a million, bro . . . . .good data! | |||
| Spiderman |
Hey that's what I'm here for  Found that little guy when I was rebuilding the motor. Wish I woulda knew it was there before so when I split the cases oil didn;t run everywhere LOL | |||
| Andys |
I, Thanks for clearing that up. Always thought the Sporty tank was low enough to avoid the problem. Spider, Ooh! I'll have to go look for that screw. Never knew that was there. | |||
| Blake |
Dude, you revealed the secret screw!!! Cool.  Teach me something else. | |||
| Spiderman |
Sorry that's all I got. My 15 min of fame are up. | |||
| Newfie_buell |
Yeah, Cool Spidey, Only someone that has had the motor apart many times will know about that loacation!!! Now I can drain all the oil in my bike. Funny Story, Last Season when I first took the bike out I brought it to my local retailer for fresh tires, while there I told them to change the oil, so while they were putting the bike up on the lift they the seat was removed with the engine running. All of a sudden Poooooooooof the oil tank stopper blows sky high spewing oil out the top of the tank. Turns out I should have not topped the oil up the extra quart when I checked it before taking it in for tires. I completely forgot that the oil leaks past the check valve into the sump over a long period of time. | |||
| Dyna |
Thats why I like my bike, the oil tank is under the tranny so it cant sump down into the case. | |||
| Blake |
There's another theory that besides just gravity, that as the crankcase and the atmosphere inside it cools it can pull a slight vacuum thus helping to actually suck oil from the tank into the crankcase. Don't know if that's true or not. | |||
| Crank |
Spidey, thanks for the info. Blake, thanks for the description "the secret screw". Now I have another reason to smile when I ride. | |||
| Captainkirk |
Thanks for the response, all. After further investigation, it appears that the tank is NOT cracked...rather, somebody sealed the vent fitting/washer/seal assy. with (what looks like) epoxy or something. This still doesn't explain why, when I rode the bike 40 miles on Sunday, nothing happened. Wasn't until that 2 mile ride on Tuesday that the problem surfaced. The vent fitting is somewhat loose, BTW. Now here's a horrifying thought- my brother, the "Guru of Buell" suggested that possibly my rear isolators are going and may have pinched off the vent line...Yikes! Anybody heard of THIS one? In the mean time, I'll take your advice and drain out some oil.  | |||
| Spiderman |
Good luck Cap, Blake got another one for ya but you may know this, On the XB the three lines that go into the Swing arm/oil tank are all diffrent thread sizes so there is no chance you can cross lines. | |||
| Newfie_buell |
Well don't they just think of everything!!!! | |||
| Blake |
Cool! We're gonna hafta start a new topic just for Anthony... Everything You Wanted to Know About Your Buell, but Didn't Know to Ask... or something like that. | |||
| Captainkirk |
Update....for those who care- Took Andys's advice and drained some oil out. Before I did though, I ran the motor, then popped the cap with it running (and watched oil splash all over)....then it occurred to me. With the bike on the sidestand, the oil level is HIGHER on the vent side (I try to add oil with the bike near level), thus probably running into and filling the vent tube up-voila...no vent! This probably created the pressure in the tank, causing it to leak out of the vent fitting. I will take this to heart and 1) add oil AFTER a ride when the tank is at it's highest level, and 2) keep the oil at a lower level from now on! Duh! BTW, Andy, I was told by a 'dealer parts dude' that he wouldn't sell me the longer filter 'cause it wasn't designed to work on the sportster engine. Huh? |
Plug