Yamaha BRUIN YFM25BV Owner's Manual page 110

To change the engine oil (with or without
oil filter element cleaning)
1. Place the ATV on a level surface.
2. Warm up the engine for several minutes,
and then turn it off.
3. Place a container under the engine to
collect the used oil.
4. Remove the engine oil filler cap, and then
remove the engine oil drain bolt to drain
the oil from the crankcase.
CAUTION:
_
When removing the engine oil drain bolt,
the compression spring, oil strainer and
O-ring will fall out. Take care not to lose
these parts.
_
1. Engine oil drain bolt
3. Compression spring
NOTE:
_
Skip steps 5–11 if the oil filter element is not
being cleaned.
_
8-7
2. O-ring
4. Engine oil strainer