| Author | Message | ||
     Treadmarks |
I had a very slight oil use, not much as I change it so often that I hardly ever added any. Just like some of the other XB owners I began having the occasional sneeze and a little hesitation off idle. Never really bothered me till recently when it became worse. I read the details in the manual about finding an intake leak with the propane torch and hose. I followed the instructions and ran the engine till warm and performed the test and both the front and back tested positive for leaks. No biggie, went to the stealer and bought a set of seals and tore into the top of the bike last Saturday am. Was a pain to get the intake off, but not that big of a deal. Since the intake was off, I couldn't resist taking a peek into the intake port of the head. OH MY GAWD!  I could not believe what I saw. There was a sheit load of burnt oil caked up on the back side of both intake valves. The chunks of oil were actually pinched between the valve and the seat. I had felt a slight loss of power and a little more sneezing that usual and now I know why. I swear it looked like a 100k mile quaker state motor. Off with the muffler and other goodies holding the engine in place for rotation. Pulled the heads and cylinders for a detailed look. Combustion chamber, piston tops and intake valve face was covered with hard solid carbon (black) while exhaust valve and port were tan/white. Valve seals were visually inspected and appeared normal with no signs of damage. These are the newer orangeish seals instead of the older style. The seal is nice and snug on the valve stem, so where is the freakin' oil coming from. According to a few sources I spoke with the last 3 days, (John of John Sachs Racing and Jason at Cometic Gaskets) recently, (05 or 06) the motor company switched to what they call "hat seals" for the valves. The bottom spring seat has the seal attached to it. The bottom spring seat is designed to rotate with the beehive spring. During high vacuum situations like hot idles in traffic and decellerations, oil is sucked under the spring seat and fills the cavity between the valve guide and seal. Oil is then free to get sucked into the valve guide and find its way to the backside of the valve where it turns into gunk/sludge and then carbon.  WTF were they thinking??? My engine was not using enough oil for me to worry about. I don't trust HD stealers to work on my bike. Heck, as far as I know my bike is probably the only one like this. I will be switching to AV&V valve guides with viton seals pressed onto the guide as well as a little headwork. This seems to be what all the good head porters use for racing. Would like to hear from anyone else that has had the opportunity to replace their intake seals and looked into their ports. (Message edited by treadmarks on June 14, 2007) | ||
| Etennuly |
Just as a matter of asking what oil have you been running? And man do I know about those Quaker State engines....Ugh...when I was a teenager I worked at a Quaker State gas station/repair shop. I remember pulling a leaking valve cover off to find it filled to capacity with a solid bar of waxy sludge that I could read the Chevrolet lettering in! Chevrolet used those small rubber valve seals up to about 1980 when they went to the umbrella seals to cut down on Hydro-carbon emissions and oil consumption. | ||
| Dennis_c |
sounds like you ride like a little old lady all that carbon build up.  | ||
| Natexlh1000 |
It's still under warranty, right? | ||
| Iugradmark |
Treadmarks, Is the take away here that we are all likely in the same boat due to design changes? | ||
| Treadmarks |
Just as a matter of asking what oil have you been running? 20w50 amsoil since break in. sounds like you ride like a little old lady all that carbon build up. I've been told I drive like alot of things, but a little old lady ain't one of them. I do see more than my share of traffic on the way home, but I touch 110-120 every morning cause there is no traffic at 5:00 am. It's still under warranty, right? Yes, but in the republic of Miami I am not about to let the stealer touch it. Hell, I drove 400 miles north just to buy it. I will do the repairs myself, as usual. Is the take away here that we are all likely in the same boat due to design changes? I don't know sir. But I tell ya what, next time you clean/check/replace your air filter, hold the throttle wide open and look inside with a bright flashlight and mirror if ya got it. Look towards the ports and see if you see a black waxy residue stuck to the intake. I did notice that on mine, which is strange because I have relocated my oil vents out of the intake tract. I dissassembled the valvetrain from the heads last night, and it was just like they said. The exhaust side looked great, and the valve seals were firmly attached to the guides with no indications of oil within the seal cavity. But the intake side was a different story. I supported the valve in the seat and removed the spring and retainer. When I lifted up the lower spring seat and valve guide seal assembly, a fair amount of oil came out. The seal slipped off way easy and the inside of the seal was saturated with oil. I am convinced that the sneezing I had was due to cooked oil particulate lodged on the valve seat preventing a positive seal during the combustion process. The trail of carbon in my intake went from the injector to the valve. I have already bought the AV&V high performance bullet nose valve guides and press on viton seals. http://www.av-v.com/ValveGuides.htm The factory guides block quite a bit of the port area, so I will gain a little flow from the AV&V guides + a very mild port blending and 3 angle valve job. The chambers and piston domes will get a nice polishing as well. | ||
| Pso |
Treadmarks-I do not know if this applies to you,because I do no tknow where you keep your oil level, but over the past year or so I have been reading about folks that keep the oil level up to the top mark on the oil stick. These folks have reported that they seem to burn off a good deal of oil( I believe Eohr or whatever he went by talked about this). Then further reading the folks that keep their oil between the full mark and the add mark never need to add oil. Just my 2 cents. As an aside I am thinking of getting an oil catch can, I just wish they would come down in price a bit so that I could afford one. | ||
| Stevem123 |
Hey Treadmarks, Can you post up some pictures? I would really like to see what you found as well as the job in progress. I may want to do the same thing. BC Steve | ||
| Treadmarks |
Steve, I have already started cleaning but I will get some pics of the progress and try to show the difference. | ||
| Stevem123 |
Thanks dude! Kinda pisses me off to think there may be a real issue here. I wonder if the supposedly new part number for heads has something to do with those seals? Mine is an early 06 model. BC Steve | ||
| Iugradmark |
For the veterans on the board who know who the Buell reps are, can you ask one of them to weigh-in on this? Seems like an excellent opportunity to get some feedback from the manufacturer. | ||
| Blake |
Not sure about getting any industry folks to comment here, but we'll make sure they are aware of this thread.  |
