Page 62 - CTS - Mechanic Diesel - TP
P. 62
MECHANIC DIESEL - CITS
TASK 2: Measure the clearance between the liner and piston
• Clean the oil and dust of the piston with kerosene
• Clean the piston with compressed air and baniyan cloth.
• Clean the cylinder bore with baniyan cloth
• Insert the piston (without ring) inside of the cylinder bore/ liner
• Measure the clearance between the liner and the piston below the gudgeon pin by the feeler gauge
• Note the reading of feeler gauge leaves and compare with service manual specification.
TASK 3: Measure the clearance between the crank pin and connecting rod big end bearing
• Clean the big end bearing and crank pin
• Install the shell bearing in connecting rod and lower cap of big end
• Place the piece of gauging plastic to full width of crank pin as contacted by bearing. (avoid oil hole).
• Install the connecting rod bottom cap and tighten the nuts gradually, as follows;
a Tighten all cap nuts in hand tight.
b Retighten them as per specified torque.
c Repeat the relevant steps to all the connecting rod end caps
d Once again check the tightening torque.
• Remove the big end cap and using scale and gauging plastic width at the widest point (Clearance). If clearance
exceed its limit use a new standard size bearing and remeasure the clearance between the crank pin and
connecting rod big end bearing.
• If the clearance cannot be brought to within its limit even by using a new standard size bearing regrind the
crankpin to under size and use 0.25 mm undersize bearing
• Same method to be followed to other crank pin and connecting rod bearings.
Note: Never place plastic gauge above oil holes.
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CITS : Automotive - Mechanic Diesel - Exercise 2.19