Takeuchi TB 175 Handbuch Seite 816

4. Disassembly, inspection and reassembly of engines
Piston pin hole measurement
(b)
Measure the outside diameter of piston pin and the
inside diameter of piston pin hole. Calculate the
clearance between piston pin and piston pin hole. If any
data exceeds the limit, replace the part with a new one.
Model Item
Pin I.D.
3TNV82A Pin O.D.
Clearance
Pin I.D.
TNV84 to 88 Pin O.D.
Clearance
Pin I.D.
4TNV94L•
Pin O.D.
4TNV98 (T)
Clearance
Pin I.D.
4TNV106 (T) Pin O.D.
Clearance
Piston ring, ring groove and end clearance
(c)
measurement
• Except for the top ring, to measure the piston ring
groove width, first measure the width of the piston
ring. Then insert the piston ring into the ring. Then
insert the piston ring into the ring groove. Insert a
thickness gage in between the piston ring and groove
to measure the gap between them. Obtain the ring
groove width by adding ring width to the measured
side clearance.
• To measure the end clearance, push the piston ring
into the sleeve using the piston head, insert a thick-
ness gage in end clearance to measure. The ring
shall be pushed in to approx. 30 mm above the bot-
tom end of the cylinder. For the top ring, measure
only the piston ring joint end clearance in normal
state.
Measuring side clearance
(R.1)
Standard Limit
23.000 to 23.009 23.039
22.995 to 23.000 22.965
0.000 to 0.014 0.074
26.000 to 26.009 26.039
25.995 to 26.000 25.965
0.000 to 0.014 0.074
30.000 to 30.009 30.039
29.989 to 30.000 29.959
0.000 to 0.020 0.080
37.000 to 37.011 37.039
36.989 to 37.000 36.959
0.000 to 0.022 0.080
Width
Thickness
Measure at positions a,b and c
in directions A and B.
A
mm
B
Piston pin outside diameter
Ring components
Head surface
Cylinder block
Pistonring
Approx.
30mm
Ring joint end clearance
measurement
102
a b c
Top ring
Top ring
Second ring Second ring
Oil ring Oil ring
4TNV94L 3TNV82A
4TNV106(T) 3/4TNV88
Joint end clearance