Bar / Chain Maintenance; Guide Bar Maintenance; Chain Maintenance - MTD Yard Machines MTD1640NAVCC Manuel Del Dueño/Operador

8-1. GUIDE BAR MAINTENANCE

Frequent lubrication of the guide bar (railed bar which sup-
ports and carries the saw chain) sprocket tip is required.
Proper maintenance of the guide bar, as explained in this
section, is essential to keep your saw in good working con-
dition.
SPROCKET TIP LUBRICATION:
CAUTION
The sprocket tip on your new saw has been pre-lubricated
at the factory. Failure to lubricate the guide bar sprocket tip
as explained below will result in poor performance and
seizure, voiding the manufacturer's warranty.
Lubrication of the sprocket tip is recommended after 10
hours of use or once a week, which ever occurs first.
Always thoroughly clean guide bar sprocket tip before lubri-
cation.
TOOLS FOR LUBRICATION:
The Lube Gun (optional) is recommended for applying
grease to the guide bar sprocket tip. The Lube Gun is
equipped with a needle nose tip which is necessary for the
efficient application of grease to the sprocket tip.
TO LUBRICATE SPROCKET TIP:
WARNING
Wear heavy duty work gloves when handling the bar and
chain.
1. Move the STOP switch down.
NOTE: It is not necessary to remove the saw chain to lubri-
cate the guide bar sprocket tip. Lubrication can be done on
the job.
2. Clean the guide bar sprocket tip.
3. Using the Lube Gun (optional), insert tip of lube gun
into the lubrication hole and inject grease until it
appears at outside edge of sprocket tip (Figure 8-1A).
4. Rotate saw chain by hand. Repeat lubrication proce-
dure until the entire sprocket tip has been greased.
GUIDE BAR MAINTENANCE:
Most guide bar problems can be prevented merely by keep-
ing the chain saw well maintained.
Insufficient guide bar lubrication and operating the saw with

8 - BAR / CHAIN MAINTENANCE

8-1A
chain that is TOO TIGHT will contribute to rapid bar wear.
To help minimize bar wear, the following guide bar mainte-
nance procedures are recommended.
BAR WEAR - Turn guide bar frequently at regular intervals
(for example, after 5 hours of use), to ensure even wear on
top and bottom of bar.
BAR GROOVES - Bar grooves (or rails which support and
carry the chain) should be cleaned if saw has been used
heavily or if saw chain appears dirty. Rails should always be
cleaned every time saw chain is removed.
OIL PASSAGES - Oil passages on the bar should be
cleaned to ensure proper lubrication of the bar and chain
during operation.
NOTE: The condition of the oil passages can be easily
checked. If the passages are clear, the chain will automati-
cally give off a spray of oil within seconds of starting the
saw. Your saw is equipped with an automatic oiler system.

8-2. CHAIN MAINTENANCE

CHAIN TENSION:
Check the chain tension frequently and adjust as often as
necessary to keep the chain snug on the bar, but loose
enough to be pulled around by hand.
BREAKING IN A NEW SAW CHAIN:
A new chain and bar will need chain readjustment after as
few as 5 cuts. This is normal during the break-in period, and
the interval between future adjustments will begin to length-
en quickly.
WARNING
Never have more than 3 links removed from a loop of chain.
This could cause damage to the sprocket.
CHAIN LUBRICATION:
Always make sure the automatic oiler system is working
properly. Keep the oil tank filled with Genuine Factory Parts
Chain, Bar and Sprocket Oil.
Adequate lubrication of the bar and chain during cutting
operations is essential to minimize friction with the guide
bar.
Never starve the bar and chain of lubricating oil. Running
the saw dry or with too little oil will decrease cutting efficien-
cy, shorten saw chain life, cause rapid dulling of chain, and
lead to excessive wear of bar from overheating. Too little oil
is evidenced by smoke or bar discoloration.
CHAIN SHARPENING:
Chain sharpening requires special tools to ensure that cut-
ters are sharpened at the correct angle and depth. For the
inexperienced chain saw user, we recommend that the saw
chain be professionally sharpened by the nearest
Authorized Service Center. If you feel comfortable sharpen-
ing your own saw chain, special tools are available from
the nearest Authorized Service Center.
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