
Feuling Vent Gauge designed to replace the original oil filler cap and vent excess pressure from the crankcase via a PCV-type breather. Machined and engineered to limit blow-by accumulation in the reservoir, it features an oil separator, a perforated disc, a replaceable filter, and a non-return valve for clean and reliable operation. Made in the USA.
Tests mentioned by the manufacturer indicate a decrease in usable engine oil level, a freer engine, and a reduction in consumption and blow-by. Note: the oil suction port is located on the right side of the engine, and warming the bike on the side stand may skew the reading.
Manufacturer's ref: 3090 — particularly appreciated by owners of custom and vintage/classic touring bikes (e.g., Harley-Davidson FXDLS, FLSTFBS, FLSS).