The engine check is where a charter week is most often saved or lost. Look at the engine cold, start it yourself, test it against the lines, and write down every number that will be read again at check-out.
1 · Engine bay
Look at it cold, with a torch
What should I check in the engine bay before accepting a charter yacht?
Look at it cold, before anyone starts the engine: oil between the marks and not milky, coolant between MIN and MAX, belt with about 10 mm of give, raw-water seacock open and strainer clear, filter bowl clean, tray dry.
Ask for the engine bay to be opened before anyone starts the engine, and check it yourself. A fault found now is the base's to fix; found on Wednesday, it is yours at sea.
Engine bay, engine cold
Oil: between the marks, dark, not milky
Coolant: between MIN and MAX
Belt: about 10 mm of give, no black dust
Seacock open, strainer clear
Filter bowl: clear fuel, no dark layer
Tray and saildrive well: dry
You find
It means
Milky oil, engine or gearbox
Water in the oil: the base's job
Dark layer in the filter bowl
Water or dirt: drain, new element
Soot ring at the exhaust elbow
Exhaust gas leaking into the boat
Damp saildrive well
A seal weeping: an answer in writing
The gearbox has a dipstick too. A packed stern gland drips once or twice a minute while the shaft turns and is greased from its cup; a dripless seal stays dry. Have the tray wiped dry, so a new leak shows.
The raw-water seacock stays open: close it only to clean the strainer, while cranking a reluctant engine (open it again the moment she fires), or when you leave the boat for long. The hose looping high above the engine is the anti-siphon loop: it stops seawater creeping into a stopped engine.
2 · Starting and stopping
Start it yourself and read the panel
How do I know the engine cooling is working after I start it?
Look aft for water at the exhaust. None means no cooling: stop the engine at once, then check the seacock, the strainer and the impeller.
Lever in neutral, key on, wait for the glow-plug light to go out, then crank. At key-on the oil and charge lamps and the buzzer come on: a lamp test. They go out seconds after the engine fires.
Then look aft for water at the exhaust. None means no cooling: stop at once, then check seacock, strainer and impeller. A battery light that stays on means no charge: belt or alternator. An alarm blamed on a 'faulty sender' is no alarm; do not sign for it.
A diesel stops when its fuel is cut, by a stop button or pull handle; the key goes off afterwards. Push the handle back in.
It will not start
Panel dark: the engine battery switch
Cranks, no fire: stop handle left out
Many tries: close the raw-water seacock, each crank pumps water into the exhaust
Half a turn, then solid: water inside.
Do not crank again, call the base
3 · Gear, propeller, thruster
Test ahead and astern with the lines on
How do I test a charter boat's gearbox and propeller before leaving the berth?
Still tied up, click ahead, then astern, at idle: the boat should pull against her lines both ways. A folding propeller that revs without pulling is stuck half-open: neutral, a burst astern, try again.
Still tied up, click ahead, then astern, at idle: the boat should pull against her lines both ways. A folding propeller that revs without pulling is stuck half-open: neutral, a burst astern, try again. Neutral needs a click you can feel, and the engine should start only there.
Rule
Gear at idle only: idle, pause in neutral, click, then throttle.
Test the bow thruster in short bursts each way. It is built for seconds: held for half a minute, its thermal cut-out trips until it has cooled and its breaker is reset.
Check her speed at cruising revs in flat water on day one. Wind and chop take a knot or two; less speed in flat water, or black smoke at high revs, means an overloaded engine: ease back and have the propeller looked at.
4 · Fuel
See it full, mark the filler, count the hours
How do I work out how much fuel a charter yacht has used?
Count engine hours times the hourly burn the base gives you; gauges read in quarters and stick. 'Full on handover, full on return' only works if you saw the tank full: a dip, a sight glass or the fuel quay.
'Full on handover, full on return' works only if you saw it full: a dip, a sight glass or the fuel quay. Gauges read in quarters and stick, so count engine hours times the hourly burn the base gives you.
Fuel plan for the week
Tank 160 L, keep 20 L: 140 L to use
Burn at cruising revs: about 4 L/h
140 ÷ 4 = 35 hours of motoring
Plan: 6 h a day × 6 days = 36 h = 144 L
So: a fuel stop midweek
Rule
Gauge and hours disagree: plan on the worse one. The reserve is not for planning.
Deck fillers: smell, then mark the diesel cap with tape.
Fuel quay: a slow flow, stop at the first gurgle.
Fuel shut-off: along the pipe is open, across is closed. The whole crew sees it: in an engine fire it is closed.
Petrol lives on deck, never below: its vapour sinks into the bilge.
An engine that surges and dies in a seaway has a blocked filter: rough water stirs a dirty tank. Sail or anchor, drain the bowl, fit a spare element, call the base.
5 · Hours, spares and the form
You sign for what you were shown
Why do I need to record the engine hours at charter check-in?
The engine hours on the check-in form are what the week is measured against at check-out. Write what the panel shows, photograph it, and have a wrong figure on the form corrected before you sign.
The engine hours on the form are what the week is measured against. Write what the panel shows and photograph it.
Meter not counting: write it on the form, with how the base will charge instead.
A clause limiting engine hours: get its meaning in writing.
Not shown, like the propeller of a boat afloat: write 'not seen'.
Catamaran: both engines opened, both hours noted. A generator is a third engine, with its own seacock, strainer and hours.
Spares are useless without tools. Ask for a spare impeller and its puller, hose clips and the engine manual, and have the inventory corrected to what is aboard.
6 · During the week
Stop first, find out second
What do I do if the engine overheat alarm goes off at sea?
Stop the engine before it seizes: after an overheat alarm, sail or anchor, let it cool, then check strainer, impeller and belt. On a catamaran, stop the hot engine and carry on with the other.
Each morning: oil, coolant, belt, strainer, a dry tray. Top the oil up to the upper mark, never above; tell the base about an engine that needs a litre a day.
An overheat alarm means stop before the engine seizes: sail or anchor, let it cool, then check strainer, impeller and belt. On a catamaran, stop the hot engine and carry on with the other.
Exhaust
Meaning
White on a cold start
Normal: it clears in a minute
White that stays, temperature rising
Steam: stop
Black at high revs
Overload: ease back, check the propeller
Blue haze
Burning oil: top up, tell the base
To charge at anchor, run an hour at about 1,500 rpm: hours at tick-over charge little and harm the engine.
Practice questions
Questions from this topic, as the app asks them. Open one to see the answer.
Engine bay, before starting
Dipstick: at the top mark, milky grey
Header tank: below MIN
Belt: firm, a little black dust
Tray under engine: dry
The technician lifts the companionway steps and lets you pull the dipstick and open the header tank yourself. What do you ask for before you sign?
A litre of coolant to top up yourself, with the oil colour noted on the form
Nothing — oil goes grey after a season of short runs in the marina
The base to find why the oil is milky and to fill the coolant before you leave
To run the engine hot for ten minutes and look at the dipstick again
Show the answer
C. The base to find why the oil is milky and to fill the coolant before you leave
Milky oil is water in the oil — a heat exchanger or gasket fault; the base fixes it, not you at sea.
All 50 questions of this topic are in the app: practice by topic with the reason after every answer, your mistakes brought back, and a timed mock exam. Free, no sign-up, in the browser or in Telegram.
