Author |
Message |
Tpoppa
| Posted on Friday, October 23, 2009 - 11:48 am: |
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My 03 XB9S burned little to no oil after the breaking period. My 05 XB9SX, burns a little. It runs just fine, makes good power, no smoke, etc. What could cause it to burn oil? |
Greg_e
| Posted on Friday, October 23, 2009 - 12:45 pm: |
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Is it buring while you ride or after it sits? Could be dripping down the valve guides while it sits and new seals would probably fix it. Could just be the way the rings sit on the cylinders. Could be bad PCV valves which are cheap and "easy" to replace. A catch can would tell you what is happening with the PCV valves to see if an excessive amount of oil is blowing past them. The other things are harder to diagnose. You could try a compression check on the cylinders to see about the rings. And the valve seals you might as well just replace if you are going to tear down that far to check them. I would expect the service manual to have a list of things to check and how to check them so if you don't have one you might want to order one. |
Aptbldr
| Posted on Friday, October 23, 2009 - 12:46 pm: |
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I'll guess there are more opportunities for variance/mis-fit & oil movement between rings, pistons & cylinders; than between valve-stems & seals. |
Tpoppa
| Posted on Friday, October 23, 2009 - 01:19 pm: |
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I hadn't considered the PCV valves, but that just may be the issue. I have noticed more oil in the airbox than on my previous XB9. At times the idle will fluctuate a bit say down to 950 rpm. Otherwise it runs strong. I never looked into a catch can, I'm guessing it connects to the hoses on the PCV valve. |
Midknyte
| Posted on Friday, October 23, 2009 - 02:35 pm: |
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I have noticed more oil in the airbox than on my previous XB9 You might be actually over-filling it then. Excess oil will be dumped into the airbox. Check your level after the bike has been warmed up or been ridden for a while. |
Hughlysses
| Posted on Friday, October 23, 2009 - 03:19 pm: |
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...and don't feel obligated to keep the oil level at the top of the XXX's. Bottom to middle of range is fine with hot oil. |
Fast1075
| Posted on Friday, October 23, 2009 - 05:37 pm: |
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A compression test, leakdown test and close inspection of the plugs go a long way towards identifying oil usage...oil blowing into the airbox may indicate blow-by in the cylinders...but is fairly common in any case...the valve guide seals in many engines have been problematical...and of course over filling is another issue. Another problem often overlooked is improper break-in of the motor...or the premature use of synthetic oil... Leak it down...if ok...fresh plugs...change to dino oil and go flail the hell out of it for a couple thou miles...if it still uses oil then, keep an eye on it and keep oil in it until it gets bad enough to be a problem. When I bought my first Buell...it used oil...it passed leakdown and the plugs looked pretty good...I "re-broke" it in with dino oil...changed that to Mobil 1 20-50 V-twin oil...problem solved...in my case, the engine had been run so gently, the rings never broke in properly. |
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