On a Honda 150, should I run engine before changing engine and gear oil? I have read yes and no. The no side said there is a backflow valve that keeps the oil up in the warm engine and hence not all will drain out until that valve opens after sitting for a while. Is this the case on a Honda?? Thanks.

No valve but engine needs to tilted up slightly for 5 minutes to allow oil from valve cover to drain back down into oil pan.

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