Answers to the Oil Final Exam

I feel these were all very difficult questions. You would be doing well to get 10 correct.

1- While starting up your car at 75 F, mid-winter in Florida, which of these synthetic oils provides the least startup resistance, minimal battery and starter motor load?
A- 0W-20
B- 0W-30
C- 0W-40
D- 0W-50
E- They are all exactly the same
The correct answer is A- 0W-20.

2- While vacationing in Orlando, it is 104 F mid-summer in Florida. The rental car company put a straight mineral based 30 weight oil in their car because they wanted the operating temperature viscosity to be at 10 cS. What will be the approximate viscosity of the oil when you start up your engine now?
A- 10 cS
B- 20 cS
C- 30 cS
D- 100 cS
E- 400 cS
The correct answer is D- 100 cS

3- While vacationing in Florida you are able to race your car at the Sebring track. At an oil temperature of 302 F what is the approximate difference in viscosity between a 20 and 40 weight oil. Pick the closest number.
A- 1
B- 10
C- 20
D- 40
E- 400
The correct answer is A- 1

4- Assume there are no losses in the system and your oil pump is truly volume based. Also assume there is no cut off pressure valve and you are using a 40 weight motor oil. If at 1,000 RPM your pressure is 30 and your pump output is 1 (one), what will the pressure and output be at redline, 8,000 RPM?
A- 240 PSI, flow = 8
B- 180 PSI, flow = 8
C- 240 PSI, flow = 4
D- 180 PSI, flow = 4
E- 120 PSI, flow = 8
The correct answer is A- 240 PSI, flow = 8

5- Water can be used as a lubricant.
A- True
B- False
The correct answer is A- True

6- If you increase the pressure in a bearing, all other things being constant, the force of separation between the parts increases.
A- True
B- False
The correct answer is B- False

7- The best weight oil for racing any Ferrari or Lamborghini is a 40 weight multigrade synthetic oil like Mobil One 0W-40.
A- True
B- False
The correct answer is B- False. It can best be determined by driving the car with one type of oil and see what happens.

8- For my Maranello 575 the 0W-20 weight Mobil 1 oil is actually too thick for my driving conditions.
A- True
B- False
The correct answer is A- True

9- The major problem with engine oil is that it thins with increasing temperature.
A- True
B- False
The correct answer is B- False. The problem is thickening when the engine is turned off. With long term use the problem is also thickening.

10- Your 1993 sports car manual states to use an API / SAE SH rated 10W-40 mineral based motor oil. Your engine has only 4,550 miles on the odometer. On your next oil change it would be better to use a SM rated 0W-40 synthetic oil.
A- True
B- False
The correct answer is A- True

11- According to SAE J300 a 0W-30 and a straight 30 weight oil must have a viscosity of between 9.3 and 12.4 centiStokes at operating temperature (212 F).
A- True
B- False
The correct answer is A- True

12- In my list of recommended oils what did I list as the best mineral based motor oil in the 50 weight class?
A- Pennzoil multigrade 20W-50
B- Castrol GTX 20W-50
C- Red Line 15W-50
D- Valvoline Durablend 20W-50
E- No oil was recommended
The correct answer is E- No oil was recommended. They all are too thick at startup for daily use.

13- You are running 5W-40 Shell Helix Ultra fully synthetic motor oil in your Mercedes Benz. You are in a K-Mart shopping center and checked your oil and it is 1 1/2 quarts low. You will need to add one can of oil now. Which of the following is the best choice.
A- Mobil 1 - 0W-40
B- Pennzoil Synthetic 5W-40
C- Red Line Synthetic 5W-40
D- Castrol Syntec 0W-30
E- Shell mineral based 10W-40
The correct answer is E- Shell mineral based 10W-40. You can mix any SM rated oil in there but this is my first choice based on my research.

14- Motor oils that are labeled “for racing only” should not be used for everyday driving because:
A- They do not have detergents
B- They may have harmful levels of some additives
C- They are generally unrated, there is no SJ, SL or SM approval
D- You would have to take your engine apart and clean it periodically
E- All of the above
The correct answer is E- All of the above

15- ASTM stands for:
A- Automotive Standards and Test Methods
B- Automotive Society for Tooling and Machining
C- American Society for Testing and Materials
D- American Standards Trade and Manufacturing
E- Society for American Standard Testing Methods
The correct answer is C- American Society for Testing and Materials

16- If your engine is running too hot at higher RPM one thing you can try to bring the temperature down is to use a thinner oil.
A- True
B- False
The correct answer is A- True

17- Oil with a startup thickness of 100 (at 75 F) that becomes the appropriate thickness of 10 when fully warmed up (212 F) is called a 10W-30 weight motor oil.
A- True
B- False
The correct answer is A- True

18- A main advantage that the synthetic has over the mineral based oil of the same grade is the ability to lubricate better at startup.
A- True
B- False
The correct answer is A- True

19- In ASTM D 4485 3.1.4: Engine oil is defined as - - “a liquid that reduces friction and wear between moving parts within an engine, and also serves as a coolant.”
A- True
B- False
The correct answer is A- True

20- I am (single best answer):
A- Surgeon
B- Biochemist
C- ‘Halfass mechanic
D- Absurdly interested in motor oils
E- All of the above
The correct answer is E- All of the above

 

You would be better mixing a non synthetic with a synthetic than two different synthetics. The weights are less important.

I would mix Pepsi and Coke however.

aehaas