Skip to main content

Effects of improper tappet clearances

If tappet clearance is less:
I. Valve will open early & close late
ii. Air induced through inlet valve may leak out. So less air for combustion.
iii. Power will be reduced.
iv. Fuel consumption will increase, engine may become unbalanced, exhaust temp. will be very high.
v. In worst condition, valve may remain open; resulting in loss of compression pressure, burning of    exhaust valve, T/C fouling will increase.
 
If tappet clearance is more:
I. Valve will open late & close early.
ii. Lesser heat energy to T/C, so reduction in scavenge air & hence power.
iii. No proper removal of gases.
iv. Hammering of valve stem-may cause damage to valve stem.

Comments

Popular posts from this blog

Why atomisation test should not be done in slide type fuel valves

Since very small needle lift is obtained in the test equipment result in an unequal pressure distribution in the cut off shaft resulting in a hard contact in a small area along with high frequency oscillations, low lubricity of test oil will increase the chance of seizure. Full lift and high lubricity of heavy oil eliminates this risk  of seizure during normal operation.( Always open and clean slide type valves before testing as cold sticky heavy oil along with small clearances can cause restriction in the movement of the spindle).