Evolution Oil and Transmission Fluids
Mike RoenDescription
It is important to run the motorcycle until it reaches full temperature prior to pulling any drain plugs. This allows for a better oil drain, and also; any engine oil that may have sumped into the bottom of the crankcase will be scavenged and returned back to the oil tank prior to draining. Let the motorcycle and the oil cool a bit while you disconnect the negative battery cable from the battery or from the frame.
On an Evolution Softail, the engine oil is drained from the oil drain hose located on the bottom, right side of the oil tank. The drain hose on early Evo models is secured to a nub on the frame with a screw-style clamp. On later models, the drain hose end is blocked with a steel plug. The plug is also secured with a screw clamp and is retained to the motorcycle’s frame with a small, bendable metal strap. Mike pulls the oil drain hose from the frame nub to drain the engine oil. The oil fill plug/dip stick is removed as well as the oil filter.
Next, Mike removes the front muffler for better access to the transmission drain plug. The drain plug is removed with a T-40 torx bit and the transmission fill plug is removed with a 3/8″ Allen wrench. Mike uses a drag link to remove the tappet screen plug located on the crankcase near the rear tappet block. The screen and spring are lifted out with a pick. Before thoroughly cleaning the screen, Mike takes the time to inspect for any possible grime or debris that may have been captured. The cap is reinstalled with a new o-ring.
*Note: If you do not own a drag link for removal and installation of the tappet screen plug and oil pump plugs, it is possible to remove the plugs with a brass punch. The plugs can be re-tightened with a number 3 screwdriver.*
Mike reinstalls the engine oil and transmission oil drains. Harley Davidson 1340 Evo engine oil capacity is 2 to 2.5 quarts of oil and is poured into the oil tank. Final oil level will be set after the engine has been started and warmed.
The transmission will take approximately 24 oz of fluid. Mike starts by pouring 20 to 22 oz into the fill hole in end cover. Final transmission oil level is set after the thick transmission oil settles in the case.
Critical fasteners are checked throughout this service. Since the rear shock bolts are easily accessible with the front muffler removed, Mike checks these fasteners for proper tightness at this time.