15Checking the spark plug– Only use the supplied universal wrench to remove or to install the spark plug.– The gap between the two electrodes of the spark plug should be 0.6-0.7 mm(0.024”-0.028”). If the gap is too wide or too narrow, adjust it. If the spark plugis clogged with carbon or dirty, clean it thoroughly or replace it.CAUTION: Never touch the spark plug connector while the engine is running(danger of high voltage electric shock).Supply of grease for the flexible shaft– Supply grease (Shell Alvania 2 or equivalent) to the flexible shaft every50 hours.(Genuine MAKITA grease may be purchased from your MAKITA dealer.)To apply grease, perform the following steps:1. Remove the bolts (A) and (B).2. Remove the head unit from the shaft.3. Pull out the flexible shaft by hand and apply grease.Suction head in the fuel tank– The fuel filter (1) of the suction head is used to supply the fuel required by thecarburetor.– Visually inspect the fuel filter periodically. To inspect the filter, open the fuelfiller cap, use a wire hook and pull out the suction head through the tankopening. Replace the filter if it has hardened, become particularly dirty, orclogged.– Insufficient fuel supply may result in the maximum permissible speed beingexceeded. Therefore, the fuel filter must be replaced at least quarterly toensure satisfactory fuel supply to the carburetor.(A)(B)(1)Any other maintenance or adjustment work that is not described in this manual must only be performed by authorized service center.0.6 mm-0.7 mm(0.024”-0.028”)