Operation; Chain Tension; Breaking-In The Chain - Efco MT 5200 Operator's Instruction Manual

OPERATION

Chain Tension

WARNING: Never touch or adjust the chain while the
motor is running. The saw chain is very sharp, always
wear protective gloves when performing maintenance
to the chain.
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1. Stop the engine before setting the chain tension. Loosen
the guide bar nuts slightly, turn the chain tensioning screw
clockwise to tension the chain. Refer to Assembly-Assembling
the Bar and Chain Section. Retighten guide bar nuts. A cold
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chain is correctly tensioned when there is no slack on the
underside of the guide bar, the chain is snug, but it can be
turned by hand without binding.
For warm chain, see Item 3.
2. Chain must be retensioned whenever the flats (A) on the drive
link tangs hang out of the bar groove. See Fig. 29.
3. During normal saw operation, the temperature of the chain will
increase. The drive link tangs of a correctly tensioned warm
chain will hang approximately .050" (1.25 mm) out of the bar
groove. See Fig. 30. To help determine the correct warm chain
tension, the tip of the combination wrench (Fig. 31) can be
used as a guide.
CAUTION: Chain tensioned while warm, may be too
tight upon cooling. Check the "cold tension" before
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next use.
CAUTION: A new chain has to be retensioned more
often than one that has been in use for some time.

Breaking-in the Chain

New chains will stretch and must be tightened frequently.
Lift the chain out of the bar groove and lubricate the bar groove
with additional oil, see Fig. 32. Place the chainsaw on a piece
of cardboard or scrap plywood. Start the chainsaw (refer to
the Operation-Starting Engine Section) and allow it to run at
moderate speed for approximately one (1) minute. Stop the
engine. Check that the oil pump is working properly. The
cardboard should have excess oil from the chain rotation if
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the oil pump is working properly, see Fig. 33. Adjust the chain
tension (refer to Operation-Chain Tension Section). Start the saw
again and make a few cuts in a log to heat up the chain. Stop
the engine and re-adjust chain again. Repeat this process until
the chain retains proper warm tension adjustment as shown in
Fig. 30 in Operation-Chain Tensioning Section. Never touch the
ground with the chain.
33
en
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