Deck 10: Two-Stroke Engine Top-End Inspection

Question 1

What procedure should you use to start a freshly rebuilt engine?

Answer 1

Make certain that all of the reassembled components are in place and all fasteners are properly tightened. Make sure all fluids are topped off and kick the engine over. It should start within 10-15 kicks. Let the engine idle once it's been started and check for leaks. Shut the engine off and top off the coolant once it has reached room temperature.

Question 2

Explain how a power valve works and what affect it has on engine power.

Answer 2

A power valve works by opening and closing valve near the exhaust port. Most power valves move shafts in and out to change the height of the exhaust port. By varying exhaust system volume and port height the useable power of the engine can be greatly extended.

Question 3

A stuck piston ring often results from over heating the oil.

Answer 3

True

Question 4

Explain the importance of proper piston to cylinder clearance.

Question 5

______is the difference between the largest cylinder bore measurement and the smallest on the same axis.

A)Out of round
B)Parallelism
C)Taper
D)Warpage

Question 6

The side of the piston running parallel to the length of the wrist pin axis is called the__________.

A)thrust face
B)crown
C)ring land
D)pin boss

Question 7

A(n)____ is used to measure ring side clearance.

A)micrometer
B)feeler gauge
C)caliper
D)dial gauge

Question 8

Describe how a technician services a power valve and what tools are used.

Question 9

Deglazing is done correctly if the cross hatch angle is _____________degrees.

A)45
B)60
C)90
D)120

Question 10

A dial bore gauge can be used to check the piston to cylinder clearance.

Question 11

Scuffing and scoring are two words for the same thing.

Question 12

Explain how you perform a compression check and what it is actually measuring.

Question 13

A straight edge is used to check the cylinder head for warpage.

Question 14

You must remove the engine to service the top end of a two-stroke motorcycle engine.

Question 15

The _______ is the uncut area between the ring grooves.

A)thrust face
B)crown
C)ring land
D)boss