Engine Measurement

1
Engine Measurement Wear Analysis

• A Visual Guide

2
Objectives

• This lab is designed to teach students how to
• Analyze wear in an internal combustion engine.
• Utilize measurement equipment.
• Record accurate measurements.
• Evaluate engine condition based upon wear.

3
Measuring Cylinder Bore
Tools Dial Caliper or 3 Micrometer,
Telescoping Gauge. Procedure 6 measurement
points. 2 _at_ TDC, 2 _at_ cylinder center, 2 _at_ BDC.
For each set, one is parallel to the crank, while
the other is perpendicular.
4
Measuring Cylinder Bore
Measuring the telescoping gauge
5
Measuring Ring End Gap
Insert one ring at a time approximately 1 below
TDC. Utilize the piston to push the ring into
the cylinder
6
Measuring Ring End Gap
Use a flat feeler gauge to find the rings end
gap measurement
7
Measuring the CrankshaftMag. Journal
Use a 1 micrometer or dial caliper
8
Measuring the CrankshaftCrank Pin Journal
Use a 1 micrometer or dial caliper
9
Measuring the CrankshaftPTO Journal
Use a 1 micrometer or dial caliper
10
Measuring Connecting Rod Clearance
Approximately 1/4 of plastigage is needed.
Place the plastigage in the connecting rod cap as
shown.
11
Measuring Connecting Rod Clearance
Torque the connecting rod cap bolts to the proper
torque specification. It is extremely important
to hold the connecting rod and the crankshaft
still. If not, the plastigage will be ruined.
12
Measuring Connecting Rod Clearance
Remove the connecting rod cap, being careful not
to spin it around the crank. Compare the
flattened plastigage to the scale on the
plastigage packaging. This will give you the
connecting rod clearance.
13
Measuring the Camshaft Lobes
Use a 1 micrometer or Dial Caliper
14
Measuring the Camshaft Journals
Use a 1 micrometer or Dial Caliper
15
Measuring Valve Tappet Clearance

• This final set of measurements must be taken
  during the reassembly lab.
• Alls internal parts must be in place before
  tappet clearance can be determined.
• Do not insert the valve springs to take these
  measurements.
• Rotate the piston to TDC on the Compression
  Stroke to take tappet clearance measurements.
• This ensures that the valves are fully closed.

16
Rotate Piston to TDC on Compression
Top Dead Center
Both Valves Closed - No Overlap
17
Measuring Valve Tappet Clearance
With your thumb on top of the valve, use a flat
feeler gauge to determine the intake and exhaust
valve tappet clearance.
18
Adjusting Tappet Clearance

• If valve clearance is not in the acceptable
  range, they must be adjusted.
• If clearance is too great - Re-face seat and
  valve face, then grind stem end to appropriate
  clearance.
• If clearance is too small - Grind stem end only.
• All adjustments are made with the Sioux valve
  machine and Neway cutting kits.
• See instructor

19
Completion of Wear Analysis

• Upon Completion of your wear analysis sheets
• Make sure that all tools and equipment are
  accounted for.
• Check to be sure that all measurements have been
  recorded correctly along with your appropriate
  evaluation remarks.
• Hand-in your wear analysis sheets.
• Proceed with reassembly - Step 9.