Piston Assembly; Piston Diameter Check; Piston Stroke Clearance Definition - Husqvarna TC449 Workshop Manual

H01756
H01755
H06461
ENGINE DISASSEMBLY/REASSEMBLY

Piston diameter check

Check
• Measure piston diameter (A) crosswise to piston pin axis.
• Size (B) defines the reading beyond piston pin lower edge.
Technical specifications
Piston diameter
Tolerance group 1
Piston diameter
Tolerance group 2
Result: Piston diameter is outside tolerance values
Action:
Replace piston.

Piston stroke clearance definition

Check
• Piston diameter (B) less cylinder diameter (A) = piston clearance.
Technical specifications
Piston installation
clearance
Result: Piston stroke clearance is outside tolerance values.
Action:
Replace piston and cylinder.

Piston assembly

• Fit piston with the arrow pointing to exhaust side.
Caution
Comply with the markings for cylinders and pistons unit.
The marks denoting cylinder and piston groups must match.
F1.56
New, transverse
450
to piston pin axis,
97.925
above piston lower
edge by 4 mm
480
100.925
New, transverse
450
to piston pin axis,
97.935
above piston lower
edge by 4 mm
480
100.935
0.06...0.08 mm
1 edition (08-2010) _Rev. 11-2010
st
+0.005
mm
- 0.005
+/- 0.005
mm
+0.005
mm
- 0.005
+/- 0.005
mm