Could the little use damage the engine?

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cmedsailor

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Hello,
Most of the times when I go for sailing I turn off the engine as soon as I get out of the marina and only turn it off when I am back. So, the engine in total works very little (15-20 minutes in total) probably not long enough to bring it into “normal operating temperature”. Could this be damaging the engine?

PS: I believe a lot of people out there do the same.
 
In short yes! And the fact that many others do too is one of the main factors in deterioration. Short bursts are bad, small throttle openings are bad, but so is hammering the bejesus out of it when cold, so go out, get it warm on moderate throttle openings and then give it a good run for as long as possible at at least 3/4 throttle.
 
It's good practice to at least run the engine up to operating temperature, this will also ensure the power to start has been replaced in your battery.

Perhaps the odd trip on calm days will help.

Avagoodweekend......
 
[ QUOTE ]
It's good practice to at least run the engine up to operating temperature, this will also ensure the power to start has been replaced in your battery.

[/ QUOTE ]

How long - approx - does this take in typical UK air temps of 10 to 15c?

I would normally start the engine before I get ready to sail - so 10 mins of playing with halyards / shore lines etc plus I engage fwd and astern to make sure the thing turns etc pre departure.
 
I second Flipper. With mine I would start the engine as soon as Im on the boat and get the rest of the boat all prepped. When it comes to leaving the engine is warmed, and better still has warmed while idling. It also means that if the engine is going to cut out because of any dirt etc in the carb, it'll cut when im safely tied up.
 
Most engine wear happens in the period immediately after starting . But you are not starting your engine any more often than you would be if you ran it longer, so logically you cant be any worse off in that respect. What wont help however, is not getting the engine oil up to the temp at which water produced in combustion is boiled off. But if you change the oil reasonably regularly, I wouldnt worry.

Nor would I worry too much about starting current. If your starter motor is 1000watts and you run it for 10 sec to start the engine, then you will have taken a quarter of an amp hour out of (say) a 200 amp hour battery bank. If your alternator charges at a miserable 20 amps during your short running time, you will have replaced that leccy in less than 2 minutes. Mind you, that doesnt take into account any leccy used whilst sailing.

But then if you've been doing this for months or years without a flat battery - why worry!

The thing to avoid is running your engine on the mooring / pontoon just to charge up the batteries. Thats an extra wear inducing start up, and you're running at light load too.
 
It is unlikely to reach working temperature in 10 mins, of ticking over. You have a temp gauge? Then use that to let you know, if not 15mins, turning the prop on your mooring, in astern would do it more than likely, it needs to get the heat through the engine, to evaporate and moisture from inside the engine, as well as getting the oil hot and round everywhere and tolerances closed up, no or little use of diesel engines is death to them. As can be seen with so many low use engines junk/burning oil after only couple of thousand hours, which is nothing. Give it a damn good blasting once a month and it will reward you, with low oil consumption and reliability..
 
Running a diesel engine with no load in the marina is another way to kill it.

Start it and off you go, it will warm up very quickly under load. Take the engine cover off, locate the top of the thermostat and when it opens (it gets very hot all of a sudden) then the engine is just about at operating temp. So how long did that take? That's how long it takes to warm up.

PS get someone else to steer when you do this!
 
You took the words out of my mouth.

Running a marine diesel at tickover will not raise its temperature very much.
Do your other preperations, single up your lines, start the engine and then go. When you get the water temperature gauge reading normal you ideally want at least 30 minutes running at that temperature. Remember that is the temperature of the cooling water, not the engine or engine oil. If you habitually run the engine less than this you will get exessive corrosion, sludge in the oil, glazed bores and carbon deposits, all of which shorten the life of an engine. Remember, the diesel is like the human body, you have to use it or you will lose it! Starting it and pottering for 10 minutes out of the marina is like you getting out of bed, staggering down stairs and falling out of your house into your car. Go for a good run every day and you will live longer!
 
[ QUOTE ]
Go for a good run every day and you will live longer!

[/ QUOTE ]

I was begining to like you, then you went and spoilt it! /forums/images/graemlins/laugh.gif
 
Sorry /forums/images/graemlins/frown.gif
There is an alternative.... More lubrication! /forums/images/graemlins/smirk.gif /forums/images/graemlins/smirk.gif /forums/images/graemlins/smirk.gif
 
Wow, I had never done the maths before and didn't realise how little time it take to put the juice back in the battery after engine starting.

I have Yanmar 3GM30F - I haven't looked at the specific maths but I guess it is a similar answer. I have an old fashined 1-2-off and always kept the engine battery charging for 30 mins before turning it back to charge the domestics.

Perhaps I was wasting my time - I will cut it down. And come back to blame the forum if I end up with a flat battery

/forums/images/graemlins/wink.gif
 
I agree with Boatmike: running the engine just for ten minutes or so from cold does it no good at all: the oil never gets warm enough to pick up and remove contaminants and sludge. The block never warms through properly so that internal condensation never gets properely boiled off, resulting in internal corrosion, including pitting the valve springs which may then break.

The head never warms up properly, so is subjected to uneven expansion stresses producing head gasket problems.

Running cold or cool means inefficient fuel combustion so the injectors, cylinder and exhaust will get carboned up leading to reduced eficiency, lower power output, increasingly poor starting, rough idling, rough running, smoke...

In other words - dont!

Of course, not every engine treated this way will produce all - or even any - of these symptoms, except carboning up which they will all do without fail. But why risk expensive repairs?

Its not for nothing that commercial sea angling boats go roaring around at full throttle when they are not actually fishing: they are also giving their engines a good blast after idling all day to get them thoroughly cleaned out. It also gets them home to the pub quicker, but thats an added bonus!

If you MUST run your engine for only a few minutes, you should give it a good half hour blast on load at least 3/4 throttle every 10 hours or so. It will definitely reward you with longer life, better starting, and fewer breakdowns as it gets older.
 
[ QUOTE ]
What does it matter? If you only use the engine for 20 minutes a day it will outlast you anyway!

[/ QUOTE ] Unlikely. A certain law means it will let you down at the worst possible moment. That might just be embarassing, could lose you your boat - or worse.
 
Englander: [ QUOTE ]
... 15mins, turning the prop on your mooring, in astern would do it more than likely, it needs to get the heat through the engine ...

[/ QUOTE ]
skipper_stu:
[ QUOTE ]
why astern?

[/ QUOTE ]

I imagine he was thinking of being on a swinging mooring rather than being tied up alongside.

Alan
 
Because you would be pulling aft on your mooring, which is the normal strain on it, saves going round and round in circles if you went ahead. If you understand what I mean? But if tied up in a marina, then doesnt matter, astern or ahead.
 
To no-one in particular.

The concept of heating the engine to operating temperature is essential, but the thermostat opens when the head needs cooling water and as it's the hottest part of the motor there will still be parts of the motor (block, lower cylinder walls) which are not hot enough and at risk of attack from the acids produced in combustion.
A better way to judge engine temp is oil temperature. In cars you shouldn't use full throttle below about 50°C as the oil isn't providing full protection at lower temps.

When I was an ambulanceman the Ford Transits with the awful V4 engines would operate in the worst possible way
Cold Starts
Full Throttle
Short Journeys
Even though the vehicles would do normal duties during working hours the motors would be knackered after about 15,000 miles as a result of the emergency work out-of hours.
 
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