Table of Contents
Advertisement
3.17.3 Breaking In the Saw
Chain
Every assembly of moving parts,
including a chain, requires a certain
initial period after startup for the
individual components to bed in.
This period is known as "break-in".
Although the manufacturing
process is very meticulous, every
surface and hole has microscopic
irregularities which are smoothed
during break-in. Only a few minutes
are needed to break in a new saw
chain.
During this period the running and
sliding faces faces on the cutters, tie
straps and drive links are smoothed.
Almost all STIHL saw chains are
"prestretched" at the factory. This
process shortens the running-in
time and helps reduce chain
stretching.
28
3.17.4 Chain Lubrication
Apart from chain tension and
regular care and maintenance,
lubrication has the greatest
influence on the life of the entire
cutting attachment.
Frictional heat is generated in the
chain joints, between the sliding
faces of the chain links and the
guide bar as the chain travels over
the guide bar.
It is therefore necessary to
introduce an oil film between the
sliding faces and joints in order to
reduce friction to a minimum.
A certain amount of lubricating oil is
thrown off the cutting attachment as
the chain rotates around the bar. In
addition, lubricating oil is wiped off
the chain in the kerf. It is, therefore,
necessary to provide an ample and
continuous flow of oil to the bar and
chain as long as the chain is
running.
This is ensured by a fully automatic
speed-controlled oil pump on STIHL
chainsaws.
1
The oil pump (1) supplies the
necessary quantity of oil to the bar
tail (2) and from there through the
oil inlet hole (3) to the guide bar
groove. The drive link tangs
distribute the lubricating oil over the
whole length of the guide bar
groove.
The Ematic and OILOMATIC
systems (see 4.4) as well as the
Ematic ramp in the guide bar help
improve the efficiency of this
distribution process. In conjunction
with a variable-flow or reduced-flow
oil pump this system can greatly
reduce oil consumption. However,
the chain oiling system can only
function correctly if the oil tank is
filled (with approved lubricant), the
oil pump is in proper working order
and the oil channels, oil inlet hole
and the bar groove are free from
dirt.
Chain and Bar Manual
3
2
®
Advertisement
Table of Contents
