Question Worksheet #11 Camshafts, Valves and Lifters

Name:____________                                                                  Transportation Systems

Date:_____________                                                                 Mr. Wood

Question Worksheet #11 Camshafts, Valves and Lifters

1. List six possible valve defects that should be included in the inspection of a used valve.
   1. _____________________________________
   2. _____________________________________
   3. _____________________________________
   4. _____________________________________
   5. _____________________________________
   6. _____________________________________
2. Poor fuel flow into the cylinders past the valve can be caused by excess____________________
3. List three things to examine when testing valve springs.
   1. _________________________________
   2. _________________________________
   3. _________________________________
4. A worn valve guide may allow the valve to ______, thus allowing exhaust leakage.
5. Normal guide to valve stem clearance is usually about ___________.
   1. .002”-.006”
   2. .001”-.002”
   3. .002”-.003”
   4. .003”-.005”
6. If integral valve guides are used and found to be irregular, they can be ___________to fit an oversize valve stem.
7. After a valve guide has been cleaned with a special wire brush, the inside diameter can be measured with a tool called a(n) ______ _______ gauge and a micrometer.
8. Some engines have valve guides that are __________________.
9. When reaming valve guides, it is important to rotate the reamer in the _________ direction when removing it.
10. It is extremely important to wash away any ___________ after valve guide reaming.
11. Briggs and Stratton valve guides are coded by ______ and ________ on the guides.
12. What two results may occur if a valve seat is too narrow?
    1. ________________________________________
    2. ________________________________________
13. A valve seat that is too wide may not seat due to _______________ on the seat.
14. A valve seat that does not seat will warp and ______________________.
15. On some engines, valve seat ________________ can be removed and installed.
16. To counter bore for a new insert, a special counter bore is needed with a proper ______________ to guide it.

1. Specified valve seat widths normally range from____________.
   1. .030”-.060” b. .020”-.040”   c. .030”-.040”    d. .010”-.020”
2. When installing a new insert, the ___________side should be facing toward the ____________of the hole.
3. The valve seating line on the valve should be located ____________of the face.
   1. Near the top    b. Anywhere between top and bottom

1. Near the bottom  d. Near the center

1. A valve seating grinder or cutting tool must be guided with a ________________ fastened in the valve guide.
2. Valve lapping is done with a course _________ ____________ abrasive combined with special grease.
3. A tool called a ___________________ has a suction cup that attaches to valve head.
4. Valve refacing can be done on a ______.

a. Special valve grinder           b. manual valve refacer

c. valve lather                          d. all of the above

24. A valve grinding machine can, in addition to refacing a valve grinds the ends of valve ___________ and _____________.

25. Why do some engine manufacturers specify different valve clearance settings for the intake and exhaust valves? ________________________________________________________________________________________________________________________________________________

26. The tool used to measure valve clearance setting is called a ____________________.

27. Too little valve clearance can result in a burned valve __________ and ___________.

28. Insufficient clearance will cause valve timing to be _______.

            A. Advanced                          B. retarded

29. Too much valve clearance will alter valve timing and _________valve lift.

            A. Increase                              B. Decrease

30. Valve steam –to –lifter clearance is measured with a _________gauge.

31. If the engine does not have adjustable tappets, the valve clearance can be increased by grinding a small amount from the ______________________.

32. The camshaft is driven by the crankshaft and rotates _________as the crankshaft.

            A. One-half as fast                  B. One-fourth as fast

33. The part of the cam that contacts the valve lifter is the _______________.

34. The crankshaft gear and camshaft gear have ________marks that must be aligned when installing the cam.

35. The ____________ __________ release mechanism lifts the exhaust valve a small amount during cranking and release part of the compression pressure.

36. Once the engine begins to run, the automatic compression release is disengaged by ____________________ ________________.