oil and oil filter

[123joedrake]

Hi how do i go about changing my oil and clean the oil filter system, any tip would greatly appreciated.

[marzini]

Hi Joe,

I've worked out a procedure that avoids having to remove the LH clutch side-case that LM said must have taken a LOT of common sense to pull off. I say it saves replacing a gasket every time.

First, drain the oil by unscrewing the plug under the engine. Replace the plug securely after the oil has finished draining out of the engine.

The key to accessing the oil filter without removing the case even on the earliest small-port CB77 engines is by using a chopstick backwards (with its big end notched). That helps to position and maneuver the unit inside and through the constricted opening.

Loosen the port cover's screws. Pry the port cover out with two flat screwdrivers and remove the O-ring from the inside of the port opening so the oil filter will have enough clearance through the hole. Account for the whereabouts of the pin near the outside end of the shaft and the thin thrust-washer between the pin and the filter's outside facing cap.

Pull the shaft out (if it hasn't already come out with the cover-plate), letting the filter rest down inside the case. Insert the chopstick where the shaft was and maneuver the filter up with chopstick while lifting the chain off its sprocket with a wire or probe. Now coax the filter out through the case port opening for disassembly (the notch in the chopstick's end helps grab the filter unit).

Remove the clip from the filter and tap the cover off with a drift from behind and clean out the filter with solvent, brush and a soft scraper. Lubricate the cap's edges, put the 48.6mm x 1.6mm O-ring on the cap and fit the cap with its clip.

Using the chopstick, insert the unit all the way through the port opening and lay the chain over the filter sprocket using the probe. While suspending the unit with the chopstick over the shaft's seat in the engine-casting, reach in with one finger and press the filter back against the engine-casting. Pull out the chopstick and insert the steel shaft into the filter body. Now it's easy to suspend the filter with the shaft and insert the shaft into its seat. That's it.

Lubricate the case port's O-ring and install it in its groove. Double-check to make sure that the thrust-washer and the pin are in the correct position on the shaft.

The washer goes on the shaft outboard of the filter. The spinning filter's cap and the case port cover are aluminum and they will gall if that washer isn't there. Install the pin next, positioning it at 12 o'clock-or so, then install the case port cover— making sure the pin aligns with the oil galley hole's notch in the case port's cover.