Every time I added oil to my lawn mower, it would splash as it slowly glug-glugged down the funnel. So I made my own no-glug funnel with a straw and an empty plastic water bottle. Here's how: Slice off the bottom of a bottle at a 60-degree angle and discard. On the remaining part of the bottle, near the tapered end of this cut, make a hole in the plastic with a paper punch. Insert a straw through the hole and into the bottle's neck. The straw gives the displaced air in the tank a chance to escape, eliminating the glugging and splashing.
David S. Wise, Sequim, WA