Did some work on my Lifan 150 this afternoon. Head swap to test my bottom end cam per per this thread http://www.miniriders.com.au/forum/tech-talk/17334-lifan-150-diffs-pics.html#post165157
and encountered something a bit weird. Bottom line is I am wondering if anyone else has found the oil level to be particularly sensitive to over filling on this engine?
What happened in order was this:
* drained old oil
* remove stock head (careful to ensure cam sprocket stays on same teeth on timing chain).
* install different head (off my 140. Same casting, just different cam, valves, springs, honda rockers, and better ports).
* check cam timing (12 oclock on flywheel and 9 oclock on cam)
* check valve clearance (003 in and 004 out).
* head covers on. inlet on. exhaust on. fill with oil to 3/4 up the sight glass.
* hand turn over with no spark plug. Engine felt real stiff. Like binding somewhere or clutch dragging. But for sure in neutral.
* take off head covers and recheck timing and rocker action = all ok.
* while hand turning some more, some oil pumps out the hole on the right side which normally routes back up to the camshaft axis. Oil level now down to 1/4 the way up the sight glass.
* engine turns over nicely.
* Complete reassemble and attempt to start it. Starts on about the 3rd kick and runs fine. The only change was the oil level. I touched nothing else.
Anyway, questions are: could high oil level do this? I mean just 3/4 up the sight glass! Anyone else experienced this?
All seems good now. Just curious and thought others might be interested.
Cannot wait to test it with the bottom end cam. I'm expecting at least 15% more bottom end than the stock 150. About the same mid (which is nice in the stock 150). Maybe 15% torque loss in the top revs, but who cares, I want lower lap times not peak HP. All up I am hoping for more even torque across the revs and to fill in the flat bottom end before the mid range hit.
and encountered something a bit weird. Bottom line is I am wondering if anyone else has found the oil level to be particularly sensitive to over filling on this engine?
What happened in order was this:
* drained old oil
* remove stock head (careful to ensure cam sprocket stays on same teeth on timing chain).
* install different head (off my 140. Same casting, just different cam, valves, springs, honda rockers, and better ports).
* check cam timing (12 oclock on flywheel and 9 oclock on cam)
* check valve clearance (003 in and 004 out).
* head covers on. inlet on. exhaust on. fill with oil to 3/4 up the sight glass.
* hand turn over with no spark plug. Engine felt real stiff. Like binding somewhere or clutch dragging. But for sure in neutral.
* take off head covers and recheck timing and rocker action = all ok.
* while hand turning some more, some oil pumps out the hole on the right side which normally routes back up to the camshaft axis. Oil level now down to 1/4 the way up the sight glass.
* engine turns over nicely.
* Complete reassemble and attempt to start it. Starts on about the 3rd kick and runs fine. The only change was the oil level. I touched nothing else.
Anyway, questions are: could high oil level do this? I mean just 3/4 up the sight glass! Anyone else experienced this?
All seems good now. Just curious and thought others might be interested.
Cannot wait to test it with the bottom end cam. I'm expecting at least 15% more bottom end than the stock 150. About the same mid (which is nice in the stock 150). Maybe 15% torque loss in the top revs, but who cares, I want lower lap times not peak HP. All up I am hoping for more even torque across the revs and to fill in the flat bottom end before the mid range hit.
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