99色精品-9色在线-99色在线-99色视频国产欧美日产一区二区三区_亚洲精品亚洲人成在线观看_四虎在线精品永久观看_免费一级a一片久久精

<source id="mkaea"></source>

<dl id="mkaea"></dl>

單項(xiàng)選擇題

Operating a diesel engine for prolonged periods, with a closed freshwater cooling system, at temperatures lower than the normal design temperature can cause （）.

A.the formation of sulfuric acid
B.a decrease in lube oil viscosity
C.a decrease in cooling water pH
D.a thermostat failure

你可能感興趣的試題

單項(xiàng)選擇題

Improper maintenance of the fuel oil burners in an automatically fired auxiliary boiler, could result in （）

A.increased fuel consumption
B.increased feed water consumption
C.fuel pump failure
D.combustion control system failure

單項(xiàng)選擇題

Which of the following conditions may need to be reduced when operating a large, low speed, main propulsion, diesel engine at low loads?（）

A.Injection pressures
B.Control air supply pressure
C.Cooling water flow through after-coolers
D.Lube oil temperature

<dl id="980k8"></dl>

<pre id="980k8"><legend id="980k8"></legend></pre>