Question 78Motor Plants - 1st Asst/Chief
70% to passWhich of the following effects will excessively cold lube oil have on the operation of a diesel engine?
AThe engine will crank slowly and may fail to start.
BThe cooling system will overheat causing the engine to stall.
CThe engine will overspeed when started.
DThe fuel oil supply will become diluted resulting in rough running.
AI Explanation
The correct answer is A) The engine will crank slowly and may fail to start. Excessively cold lube oil will increase the viscosity (thickness) of the oil, making it more difficult for the engine to crank and start. The increased oil viscosity requires more effort from the engine's starter motor to turn the crankshaft, resulting in a slow cranking speed. In extreme cases, the engine may fail to start altogether due to the resistance of the thick, cold oil. The other options are incorrect because: B) Cooling system issues would not be directly caused by cold lube oil, C) Engine overspeed is not a typical effect of cold lube oil, and D) Fuel oil dilution is not a direct consequence of excessively cold lube oil.
Related Questions
Q205:An immediate repair is required if a leak occurs in the high-pressure fuel pipin... Q58:Intercoolers installed on starting air compressors, reduce the possibility of __... Q164:When an additional load is applied to a diesel engine which is using an inadequa... Q167:The thrust bearing shown in the illustration has over eight years of ahead runni... Q84:A bronze bearing liner with a lead-tin flashing has a milky-white color over mos...
Ready to test your knowledge?
Take a Motor Plants - 1st Asst/Chief Practice ExamOfficial Resources