Furuno 851 MARK-2 - Manual (Page 12)

1. MOUNTING
1-6
Fixing holes inside antenna unit
This method requires removal of the RF unit in the antenna unit to access inside
fixing holes. Use hex head bolts, flat washers, spring washers and nuts (local
supply) to mount the antenna unit, confirming length of bolts.
1. Loose four hex. bolts to open the antenna unit. Refer to Figure 1-10 for
location.
RFunit
Hex head bolt
M10X20 4pcs.
Hex head bolt
M8X25
2pcs.
Spring Washer
M10 4 pcs.
Cover
Pan head screw
M3X8 4pcs.
Upper chassis
Square bushing
Lower chassis
Figure 1-9 Antenna unit chassis, upper chassis separated
2. Unplug connector connected between upper and lower chassis.
3. Separate upper chassis from lower chassis by removing two hex head bolts.
4. Remove cover by unfastening four pan head screws.
5. Remove connector from RF unit.
6. Remove RF unit by unfastening four hex head bolts.
7. Lay the corrosion-proof rubber mat (supplied) on the mounting platform.
8. Fasten the lower chassis to the mounting platform with hex head bolts, spring
washers, flat washers and nuts (local supply), and then coat flat washers,
nuts and exposed parts of bolts with silicone sealant. Cut a slit in rubber
bushing and insert bolt into bushing. Do not use seal washers.
9. Reassemble RF unit, cover and upper chassis.
10. Set four caps (supplied) into outside fixing holes.
11. Do steps 6-8 in “Outside fixing holes”.