Furuno 821, 841 manual Preventative Maintenance, Replacing the Fuse

4.2 Preventative Maintenance

Regular maintenance is important for good performance. Always keep the equipment as free as possible from dirt, dust, and water splashes. Make sure all screws securing the components are properly tightened.

A maintenance program should be estab- lished and should at least include the items listed in Table 4-1.

4.3 Replacing the Fuse

The 5A fuse in the power cable protects the equipment against reverse polarity of ship’s mains, overcurrent, and equipment fault. If the fuse blows, find the cause before replac- ing it. Never use a fuse rated for more than 5A–serious damage to equipment may re- sult and void the warranty.

Table 4-1 Recommended maintenance program

Period	Item	Check point	Remarks
3 to 6	Fixing bolts	Check for tightness and	Replace corroded bolts. Coat
months	for antenna	corrosion.	bolts with anti-corrosive sealant.
	unit
	Radome	Foreign material on the radome	The only recommended cleaning
	cleanliness	face will cause a considerable	agent is alcohol. Do not use
		drop in performance. Clean the	other cleaning agents; they can
		radome with a freshwater.	remove paint and markings.
	Radome	Check for wear. Permanent	If a crack is found it should be
	cover	damage to the antenna's internal	temporarily repaired by using a
		circuitry will result if water leaks	small amount of sealing
		into the radome.	compound or adhesive. You
			should then contact your dealer
			for service.
	LCD	The LCD will, in time,	Do not use chemical cleaners to
		accumulate a coating of dust	clean any part of the display unit;
		which tends to dim the picture.	they can remove paint and
		Wipe LCD lightly with a soft	markings.
		cloth.
6 months	Display unit	Check for tight connection and	If corroded, contact your dealer
to 1 year	connectors	corrosion.	for replacement.

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