Question 20Motor Plants - 1st Asst/Chief

The correct answer is C) excessive lube oil consumption. Worn diesel engine intake valve guides can result in excessive lube oil consumption because the worn guides allow oil to pass from the engine's crankcase into the combustion chamber, leading to higher oil consumption. This happens as the worn guides no longer effectively seal the oil from entering the intake valve area. The other answer choices are incorrect because: A) Increased engine breathing efficiency is the result of properly functioning valve guides, not worn ones. B) Excessive valve lash is not directly caused by worn intake valve guides. D) Lower than normal fuel consumption is not a consequence of worn intake valve guides.