Why do we change our engine oil? A seemingly innocuous question I was asked a few months ago.
Because we do? Because its dirty? Because the handbook says so? It got me to thinking and to do some research because it's not such a silly question!
Oil in our engine is there to lubricate, to prevent our engines from wearing, to cool it. Basically the moving parts of the engine 'float' on a thin film of oil which is pumped around the engine by a pump from the sump. This oil is also sprayed on the underside of the pistons to help cool them and to lubricate the piston rings and where they come into contact with the cylinder walls. To do all these things it has to remain stable under extreme pressure in the bearing areas, and it is also used in some engines to cool them. It also has to be able to negate acidic combustion products.
Seasonal grades
This story is from the Summer 2022 edition of Practical Boat Owner.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber ? Sign In
This story is from the Summer 2022 edition of Practical Boat Owner.
Start your 7-day Magzter GOLD free trial to access thousands of curated premium stories, and 9,000+ magazines and newspapers.
Already a subscriber? Sign In
Orca sink yacht in Strait of Gibraltar
Spain's maritime rescue service, Salvamento Maritimo, has reported that a 15m (49ft) yacht sank in Moroccan waters in the Strait of Gibraltar following interaction with a pod of orca.
No kill cord or lifejackets were worn during fatal powerboat crash
A kill cord and lifejacket are useless unless worn-that's the warning from the Marine Accident Investigation Branch (MAIB), following its investigation into a powerboat crash that killed a 32-year-old woman and five-year-old girl on 2 October 2022.
Multihull sail work
Brush up on multihull sailing skills before heading off on charter with Gavin Le Sueur's guide to spinnaker handling, tacking and gybing
Five top causes of engine failure and how to prevent them
Jake Kavanagh talks to Sea Start marine engineer Nick Eales about how to avoid the five major causes of an engine breakdown at sea
Sail the Atlantic with strangers
Would you sail across the Atlantic with someone you've just met? Ali Wood meets the cruising crews who've done just that
IZIBoat: simple sailing
Rupert Holmes sails an innovative catamaran design intended to widen participation in sailing among those with little time to get on the water in more conventional craft
30 WAYS TO GET AFLOAT
From tall ships to small dinghies, you needn't own a boat to sail. Ali Wood looks at the options, and how skippers can also find crew
Boats for restoring under £20,000
Duncan Kent picks the best sub-35ft sail and power boats to look for when aiming to undertake a restoration on a budget
Seaworthy dinghies for less than £500
For low cost traditionally-styled GRP trailer-sailers, consider the Foreland and the Otter available at bargain basement prices
Playing with coloured sails
Maintaining an hourglass-shaped balloon and ratcheting up the log numbers