Some relevant questions on tappet clearance and v/v
What position to carry out tappet clearance
- Answer: In a 4-stroke engine, the tappet clearance is carried out at TDC of the combustion stroke
- There are 2 TDC positions for every cycle
How to differentiate between 2 TDC position in 4 strock?
- At the combustion stroke, the fuel pump plunger would have moved upwards for fuel delivery
Why are double springs provided?
- Springs tend to skew to one direction when compressed. To counter this, a second spring is provided with a counter-skew.
- This will enable the valve spindle to be maintained in an upright position during operation.
- The secondary purpose is as a back up if one of the springs break.
Areas requires special attention:
- Valve stem
- Valve seat
- Guide bush
- Valve cage
- Valve spring
- Rotocap
- Actuating mechanism