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8391D Description 18V Cordless Hammer Driver Drill 13mm (1/2") ONCEPT AND MAIN APPLICATIONS Model 8391D has been developed as the successor model of 8390D, featuring: Single sleeve keyless drill chuck for easy bit installation/removal New tool design Dimensions: mm (") Model 8391D is available in the following variations.
Note: 1) Pay attention that the machine except Keyless drill chuck starts revolving with strong force. Do not pinch your hand between the moved machine and Vise in this step. 2) If it is impossible to remove Keyless drill chuck, use 1R359 (Chuck removing tool) to remove it. Refer to Makita repair tool list.
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P 3/ 7 epair [3] DISASSEMBLY/ASSEMBLY [3]-2. Gear Ass’y, DC Motor DISASSEMBLING (1) Remove Keyless drill chuck. (2) Gear ass’y and DC Motor can be disassembled in the order of Figs. 3, 4, 5, 6 and 7. Fig. 3 Fig. 4 Gear ass’y Housing set (R) 3x16 Tapping...
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P 4/ 7 epair [3] DISASSEMBLY/ASSEMBLY [3]-2. Gear Assembly, DC Motor ASSEMBLING The following portions of DC motor, Motor bracket and Gear ass’y have to face the same side. (Fig. 8) * Red point mark (designated as plus terminal) on DC Motor * None of protrusion side of Motor bracket * Gear assembly’s protrusion Fig.
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P 5/ 7 epair [3] DISASSEMBLY/ASSEMBLY [3]-4. Leaf Spring ASSEMBLING Before assembling Gear ass’y and DC motor, Leaf spring has to be mounted to Housing set (L) as illustrated in Fig. 12. Fig. 12 Housing set (L) Leaf spring Leaf spring [3]-5.
P 6/ 7 ircuit diagram Fig. D-1 Connecting of Lead Wire (red) Color index of lead wires' sheath to DC Motor Black red point mark Connect Lead wire (red) to the Terminal marked with red point mark. DC Motor Switch viewed from Switch viewed from Housing set (L) side Housing set (R) side...
P 7/ 7 iring diagram Fig. D-2 Housing set (L) Rear view of Housing set (L) Red point mark DC Motor DC Motor has to be so assembled to Housing set (L) that its Red point mark Switchs’ Lead wires (black, red) have to be fixed with Lead wire is positioned on the back holder.