7290-157 Lesson 5 Valve timing

Why must an engine be 'timed'?

• To allow fuel air to be ignited at correct interval

• To turn distributer at same time as valves

• To allow camshaft and crankshaft to turn equally

• to advance ignition when emissions high

When a exhaust valve remains open after tdc, this is known as?

• Valve overlap

• Valve lead

• Valve lag

• Variable valve timing

Which part is responsible for opening the valves?

• Crankshaft

• Camshaft

• Timing chain

• Timing belt

What is purpose of item arrowed?

• Checks timing chain tension

• Checks timing belt tension

• Locks Crankshaft into BDC

• Locks Camshafts in Safe position

After replacing timing belt or chain what must be done next?

• Road test vehicle

• Turn engine 720° by hand

• Apply locking fluid to bolts

• Lock engine using timing pins

What is a benefit of using Wedge designed combustion chamber?

• Simplified valve activation

• Restricted air flow

• No more than two valves per cylinder

• Limited valve diameter

What are domed piston commonly used for?

• low flame propagation

• Maintaining high compression ratio

• Lower flame temperatures

• Reduction of NOx

Which of the following is not a benefit of a 'cross flow' design?

• Exhaust gas heats intake

• Design allows multi-valve configuration

• They have greater Volumetric efficiency

• Continuous flow of gases

When both port are on same side of head it is known as?

• Side valve design

• Reverse port design

• Cross flow design

• Compound flow design