Audible alarms for low oil pressure, and for high coolant
temperature are not to be discounted, but you have to be able to hear the alarm over engine noise
. Had an oil cooler line rupture earlier this year and failed to hear the alarm for several minutes --- just a new buzzing sound against the background noise
of the engine. That was a Ho Lee Sh!t moment. No harm done as it turned out (apart from an engine compartment and bilge
covered in diesel
engine oil). Make sure the alarm is LOUD
, and maybe supplement it with a bright red flashing light visible in the sun. But the main lesson is to check and replace oil lines at the first sign of chafe, cracking, or embrittlement.