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It's come to my attention that if the oil is allowed to drain for too long (such as overnight or for several hours), a motorcycle's oil pump can lose its prime and the engine can be damaged until it begins to pump properly.
I've never had this happen but it was reported on the ZX-10R forum today. It's rare but it does happen.
To avoid this, follow the procedure in the owner's manual; warm the engine before changing the oil, and don't let it drain any longer than necessary. Fill it straightaway, and check the sight glass per the manual. I've taken to filling the oil filter before installing it, too. Can't hurt anything.
Warming it up makes sure all the oil passages are filled and the pump is primed.
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What happens is the system gets air bound, very common with Kawi 1000 motors. You need to burp the system, the procedure is simple, when you install the oil filter hand tighten and then backoff to bleed the air until oil comes out. This is actually a manufacturer suggestion on Kawi's. Your oil light should should go out within 5-10 sec. If it doesn't your still air bound.
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(08-22-2016, 11:14 PM)CIP57_imp Wrote: What happens is the system gets air bound, very common with Kawi 1000 motors. You need to burp the system, the procedure is simple, when you install the oil filter hand tighten and then backoff to bleed the air until oil comes out. This is actually a manufacturer suggestion on Kawi's. Your oil light should should go out within 5-10 sec. If it doesn't your still air bound.
Never had it happen to mine but you are right about that; apparently some engines are more prone to it than others. Here's more from the forum:
The recommendation is actually to drain and refill the sump before you touch the oil filter at all.
As long as the old filter is still in place, its anti-drainback valve will stop oil drainage through the oil pump (and if it does try to drain back, it will be pulling in oil from the still-filled oil filter and oil gallerys inside the engine, rather than air).
Once the sump has been refilled, there is now not as much siphoning trying to happen, and now you can remove and replace the oil filter.
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This used to happen a lot to the Rover engined Land Rovers. One of the suggestions in the service manual was to change the filter first and replace with a pre-filled filter before draining the pan.
It's a different oiling setup, but could be a good precaution on a bike as well.
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Been changing oil in vehicles for almost 40 years. Never heard of this or experienced anything like it.
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(08-23-2016, 11:21 AM)DAC_imp Wrote: Been changing oil in vehicles for almost 40 years. Never heard of this or experienced anything like it.
Same here. I guess we been doing it the right way.
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Who lets oil drain over night?
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A couple members have said they let theirs drain over night. Seems excessive to me, but whatever make them happy.
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(08-23-2016, 09:21 PM)Lord Popgun_imp Wrote: A couple members have said they let theirs drain over night. Seems excessive to me, but whatever make them happy.
I agree. When the oil gets down to a small drip I close it up.
I've been changing motorcycle oil and oil filters for 25 years on vintage British, modern British and modern Honda's, and this is the first time I heard about this issue.
I plan to carry on with my normal routine.
It ain't broke so I ain't gonna fix it
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One thing about this, seems it is an unusual problem since the old-timers for the most part don't seem to be aware of it, including me.
But the engine designers seem to know about it. I now understand why all manufacturers state you need to warm the engine up for ten minutes before either checking or changing the oil. It's to get all the passages filled to either get an accurate reading or to help ensure that you don't get an air lock.
One of the guys on the ZX-10R forum, a moderator who's also a retired multi-engine flight instructor and generally sharp guy (except when he disagrees with me
) suspects he may have spun a bearing because of inadvertently running his engine after starting it up with this airlocked condition. That spun bearing problem, while not endemic to that model of Kawasaki, has been reported in a few instances, as well as the airlocked condition.
That's enough to convince me to actually do what the manual says from now one, since I don't relish paying for a new engine.
