Engine oil change advice

[alanporter]

My sailboat engine has only run 28 hours this year, the last oil change being November 2005. Do I need to change this "hardly used" oil ? Thanks in advance for the usual helpful advice.

Happy New Year to all forumites !

 

[LittleShip]

Hmmm!
Alan, do I want an argument????????????????????

IMHO after 28hours I would say you don't need to. It is unlikely that after such a short period that there would be enough contaminates in the oil to cause a problem!

After some engine work on mine this year she has run for 31hours and I am not changing 3 gallons of oil after such a short period.

So,............. the next post should be the complete opposite of this one! /forums/images/graemlins/laugh.gif /forums/images/graemlins/laugh.gif

Tom

 

[Fr J Hackett]

In order to oblige, that is to say with an opposite view. Yes change the oil, its not expensive, its a simple task and diesel engines benifit greatly from reasonably frequent oil changes. Their will be some acidic residues in your oil and changing it and leaving new oil in the system will benefit you in the long run. I rarely do more than 150 hrs/ year on engine, if the wind gods are favourable less than 75hrs but still change the oil twice a year filter once.
As has been said though you are going to get 2 answers to this question both of which are firmly held by their proposers. Also buy your oil in 5 gall lots which will save you money, dont buy from chandlers and buy the correct grade for your engine which is most likely a simple oil and not the modern synthetic motor oil.

Best of luck

 

[NPMR]

I change every year however many hours run. Plus filters and fuel filters and internal anodes and water pump impellors.

Costs are really low and, to date, touching wood, hanging on to rabbit's foot and ALWAYS give Neptune a share of our booze -- we've never had a problem with the engine.

I work on the principle that there's no RAC 'out there' and I'm on my own! So better safe than sorry.

 

[duncanmack]

Alan,

The recommendation for oil changes is always given as "so many miles/hours run OR every so many months"

Oil is cheap. Engines are not. If it were mine I'd change it.

I run a fleet of vehicles in our Garage/brakedown and recovery fleet. The all do colossal mileages They fall apart before we get engine problems due to regular and frequent oil and filter changes.

 

[michael_w]

Why do you change the oil, yet pump the nice clean stuff through a grubby filter?

I know this is what Volvo reccommend. I had a conversation with one of their boat show bods, who admitted that the advice in the manual was balderdash. Change the oil and the filter at the same time. ie 100 hours.

I've stuck to the routine of 100 hrs for oil. 200, or every season for the fuel.

This has worked well for:
Volvo MD3
Volvo MD 6B
Volvo 2002
Volvo 2003T
Perkins 4108
Mercedes - (can't remember the number but 90hp)
Yanmar gm both 10 and 20
Ford 1800
B&W Alpha 2-stroke 135hp
Gardner 6LXB

 

[sailorman]

for the small cost involved, change it.
the oil is the only thing that keeps the metal bits apart.
assuming the engine oil was changed at around 10 hrs ( first service ) i might concider leaving the filter & just change the oil

 

[brianhumber]

Re: Engine oil change advice To Change or not to Change?

Oh dear, all these people changing oil just in case when its run for shock horror 50, even 100hrs.
What a waste.
Oil has a tough job but we are not in the 1950s here, its a highly researched product.
On the engines I am responsible for ( totalling over 40MW) oil is only changed when its condition dictates this is required. In some cases the engine has run for many thousands of hours before requiring changing or in standby engines on low hours ( less than 1,000 in 10 years) sometimes this has never been required. I use fuel a dam sight more corrosive than marina fuel I can tell you. Big ends/liners come out as new, its poor combustion quality and incorrect temperatures that wear out engines.
I also put this into practice on my own yacht, changes being needed after about 4 years. Interestingly dispite what all the 'experts' tell you the oil never loses its base number, showing how little sulphur is in Marina fuel these days. Does not stop the magazines repeating this tosh every year however.
Am about to change the oil this year after four years, engine now 20 years old and smoke free, starts on 7 year old ordinary batteries used on domestic applications as well, but thats another area where thousands of pounds are thrown away by owners following crap battery purchase advice as well. Eventually the message will get through that this unnessary waste of worlds resources needs to stop. One can but hope the penny will drop soon.

Brian

 

[fuss]

Re: Engine oil change advice To Change or not to Change?

I also sometimes wonder why people wish to change the oil so often. Just a thought..... If the oil appears fresh and not black and also smells good, if you know what I mean.... then surely it is still ok no matter how many hours running or years it has been in the engine.
What does the panel think???

 

[supermalc]

Re: Engine oil change advice To Change or not to Change?

Some interesting posts here, and although this may sound strange, I support BOTH views.

I've know people, with sound, engineering backgrounds, that have taught me a lot of what I know, and who have never changed the oil in engines, only adding a little when necessary.

I also know others who have changed oil very frequently, often running high milage diesels for years longer than others.

However, I feel the question here is WHY NOT change the oil, rather than do I change it, or not. If your engine holds around 5 litres, and I know some hold more, then this will only cost around £10 per year. Not a great sum, even for me, the worst paid Englishman of anyone I know.

It also depends on your personal circumstances as well. Is the engine easily accessable, and have you easy means to dispose of the old oil, are just a couple of instances I can think of quickly. Also of course. If your engine were to fail, due to sludging in the oil, or a similar incident, are you in a position to have it repaired, or can you do the job yourself. All these are relevant factors in making this decision.

A car was brought into my friends garage for a service when I was a visitor there, around 10 years ago now. The sump plug was actually rusted in. After the difficulty of removing the oil and changing the filter, it was impossible to get any oil pressure. The change had disturbed the sediment in the bottom of the sump, causing it to be sucked into the oil strainer, and blocking the system.

If your boat engine is like mine, it has no sump plug, so cleaning the sludge from the bottom is even more difficult. Far easier to try to not let it build up in the first place.

In another incident, around a similar time as the last one, one of the young men who visited the garage did a bit of banger racing. This was not the destruction derby type, but one where racing, rather than wrecking was the object. In fact you were supposed to do the first three laps without touching another car. On one occasion he took a car, that he knew had a good engine (A 1600 Cavalier in fact) as it had belonged to a friend. After only 2 laps the oil light came on, and the crankshaft welded it'self in. This was because the engine was being highly revved, and once again caused the sludge in the bottom of the engine to block the system. At the time they laughed at another person who went to the trouble of changing the oil before he went racing. But he raced his car all evening.

Your engine may never be worked very hard, especially in a boat, until one day you encounter a problem, bad weather unexpectedly arrives. You have to 'thrash' the engine i.e. run at full throttle to try to beat the storm. Or you are not too far offshore when someone has a medical emergency that requires attention. Do you really want to take the risk of this happeneing, just because you don't want to change the oil.

So I'll finish by saying again. I think the question is why not change it, rather than why.

Just trying to contribute.

 

[LittleShip]

Alan,

See I told you!!

However this gent is asking does he need to change his oil after 28 hrs, I stand by my previous post.

Tom

 

[supermalc]

Btw, Happy New Year everyone.

Hi Alan. The answer is, do it if you want to, but if you don't want to, it should not make any difference.

Let's face it, I suspect your boat is your 'toy', and changing the oil is an excluse to 'play' with it. I think it's that simple.

 

[ParaHandy]

I change the oil twice a year and the oil filter once. Boat's in the water all year round. engine's a yanmar 3gm. it does seem quite happy and sounds really pleased with itself for a short period with new oil ....

 

[ArthurWood]

Re: Engine oil change advice To Change or not to Change?

<< What a waste.
Oil has a tough job but we are not in the 1950s here, its a highly researched product.>>

Agreed. At the very least, every 100-200 hr should be fine on a boat.
It's the oil companies and marine service co's who are out to make more money by saying every 100hr or less. A bit like in the car servicing industry over here - they still recommend oil changes every 3000 miles, even if the car's manual says every 10,000. Such a waste, and drain on scarce oil resources. I'm afraid I don't agree with the attitude "it's cheap, so do it more often."

 

[cliffb]

Re: Engine oil change advice To Change or not to Change?

I agree with Arthur.
The way I look at it is that if you had a car engine you'd change the oil every 9 or 10 thousand miles. Given that you average about 40 mph in a car that equates to 225 to 250 hours. So on balance, every 200 or so hours should be fine, or at the end of the season, whichever comes first.
To some this may seem excessive. But I sure wouldn't want my engine to fail for the want of an oil change. /forums/images/graemlins/smirk.gif

 

[Chris_d]

You've got many different opinons here, oil always seems to cause this. If you change it no harm done, if you don't it won't make any difference either, maybe in another 10-15 years of changing oil every 2 years or so it might make a difference but probably something else will have fallen off by then. Boat diesels get so little use that underuse is the real killer.

Friend of mine is a farmer and ran an Isuzu trooper diesel as a general workhorse, engine was basicaly running all day, they changed the oil every 2 weeks from a 25gallon drum in their workshop. They retired it at 750000miles as it was a little bit smokey and generaly tatty, still got £1500 for it though. That longevity has to be down to the frequent oil changes, so in my opinion unless its a real pain do it every year regardless, depends how long you expect to keep the boat I suppose.

 

[brianhumber]

Re: Engine oil change advice To Change or not to Change?

Malc
I agree interesting to read why people do actually change oil. Seems to be either
its cheap so why not I cannot go wrong then
or
I do not understand what oil ( or the filter for that matter) actually does or how it functions so the more hanges the better, again I can't go wrong.

If the oil can keep rotating parts separate( bearings, small ends), cool parts ( underside of piston crowns), transport large particles( soot, paint flakes, sludge) to a filter which if left could cause contact damage, keep in suspention contaminates up to a specified level( water, fuel, combustion left overs) and has enough base left to neutralize acidic combustion products
then it does not matter how old it is or what colour it is. There does seem to be a basic ignorance here.

The magazines would do a far better job for their readers if they started explaining things like this and how people could do simple tests on oil before just changing 'just in case'.

I suspect pigs will fly over the moon before the mags would do something this useful.
It may only be say 5 litres per volvo but if you multiply that up by the numbers doing it twice a year and you are chucking a fair tonneage away. If its worth remembering to switch off a mobile phone charger equally it must be worth not changing oil before you need to ? Millions of grains of sand make a lovely beach.

Brian

 

[Avocet]

Re: Engine oil change advice To Change or not to Change?

Why can't one of the mags change the oil in a variety of boat engines, run each boat for a season and then send oil samples from each off to a lab to see what sort of condition the oil is in? A variation would be to try several different brands of oil in the same engine but this, of course, would take several years!

Interestingly, the current car diesel engines with variable service intervals can (I think) monitor some aspects of oil quality. They sometimes seem to manage a couple of years between changes in the right ciscumstances.

 

[billcowan]

Re: Engine oil change advice To Change or not to Change?

Obsevations:

Very few sailing yachts ever wear out their engines, so what oil and how often you change it doesnt really matter.

I NEVER change the oil in lawnmowers despite dire warnings in the manual, because always the rest of the mower falls to bits first. I suspect the modern AWB will die of lack of value while its moter yas years left to run, different if you own a 'classic' of course.

But then, as it has been said, oil is cheap and easily changed.

Any oil is better than NO oil.

Cadillac have a car that is lubed for life with high tech aviation style lubricant.

 

[brianhumber]

Re: Engine oil change advice To Change or not to Change?

Cliff/Arthur
Would not disagree with your running hours. I would say using good fuel in an engine with good combustion that is not on a start stop routine you can extend the careful worst case mileage stated by car engine makers considerably.
My car engine is now approaching 200,000 miles and I find I normally have to change the oil at around the 20,000 miles marker. Just passed its MOT smoke test and the injectors have never been lifted.
Yacht engine is 20 years old now and has over 5,000 hours on the meter. The one management aspect I do follow is not run off load or just on tick over to charge the batteries.

Comes back to my point of not changing oil/filters till the condition tells me too not on a just in case yearly calendar basis. However each to his own and what you feel comfortable with yourself.

Brian