Engines/genset oil change: before or after winterization?

MapisM

MapisM

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I keep hearing different theories on this.
Actually, I also seem to remember that we already discussed the pros and cons, but a search didn't point me to anything interesting...
Views welcome!
 
I take the view that its better to let the engines sit over winter with clean oil in them instead of used oil.
Also during the service any problems will be discovered sooner than later which invariably means it costs more to rectify. And if its costly you have several months to spread it over before the next season instead of the pressure of getting it done in a short space of time as the season is beginning.
 
spannerman said:
I take the view that its better to let the engines sit over winter with clean oil in them instead of used oil.
Also during the service any problems will be discovered sooner than later which invariably means it costs more to rectify. And if its costly you have several months to spread it over before the next season instead of the pressure of getting it done in a short space of time as the season is beginning.
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Good advise I do the same on our main engine.
David
 
Definately before. The oil becomes acidic so it is essential to have clean oil distributed around the engine before winterising.

Also coolant change if due.

Some other things can be left tilll later such as belt and impeller but make sure you keep a log of what has been done and what is needed before recommisioning
 
Commercial operations do not change oil just because there is an r in the month, we get a oil sample tested and base our changes/maintenance of the engines on that. This practice has been going on since the 60s to my certain knowledge because thats how I learnt to do it as a young engineer with a major oil company.

With the current reduction in Sulphur content of fuels, I doubt very much if your oil will become acidic after a season or more's use, for example my little 24 year old boat engine currently has 5 year old oil in it, the larger engines built in the 60s I look after have over 10 year + old oil in the sumps. What tends to increase gradually is suspended solids and water content and an annual test allows you to monitor this as well as giving other useful information such as ferrous, iron content, flash point etc. I have never had to change oil because it had become acidic or even approach the lower limit of alkalinity that was specified by the OEM.

Do not believe what you read in the comics.

Brian
 
brianhumber said:
Do not believe what you read in the comics.
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Not sure if you mean that YBW forums are comics...
...hang on, on second thought, sometimes they definitely are, LOL! :D

Anyway, jokes aside, I see where you come from.
I've never trusted those who recommend oil changes every season, regardless of running hours.
Also because those who give such recommendations usually sell oil at 3 times its real price, if not more.
Otoh, oil tests are probably worth making only for big, high hours commercial engines, as you also say.
Look and feel of my engines/genset oils is still not bad, but I was thinking to change them anyway this year, along with filters, just to be rather safe than sorry.
That's why the question of "when" wasn't meant as after how many hours/years, having already decided to do it, but just focused on whether before or after winterization.

Overall, I would say that the "before" view is the most popular, as also the previous replies show.
The argument against that, used from the "after" supporters, is that the oil veil distributed around the engine will be drained to the sump anyway, after some days. And during winter, the condensation will increase the water content in the oil, whether new or old. So, it's better to leave the old one in winter months, and let it drain out completely (together with the water) for a few days, before hitting the water again. After refilling with fresh oil, of course!

Wadduthink?
 
I'm in the change before winter camp, believing it is better to distribute clean oil around the engine before the winter lay-up. As you say, there is likely to be some condensation over the winter, but this should "cook-off" as soon as you get the engine hot next time.

For the sake of the cost of the oil and a couple of filters and a couple of hours with the Pela, in my view it is not worth not doing.
 
I guess my take on this is.........

In the grand scheme of things an engine oil change is relatively small money, and if there's one thing you can do to look after your engine it's change the oil.

In a prefect world you'd change the oil and filter before lay up, then once recommissioned change just the oil again. If any of us can be arsed to do this is another matter!!
 
I work for one of the largest diesel engine manufacturers in the world and many of my commercial customers never change their oil. Okay, a commercial diesel is a bit different from most of our engines, but the principles are the same.

I'm in the 'after winter' camp and will change my oil and filter before she goes back in the water due to water being absorbed. Yes, it will burn off, but I'd rather know that the bearings are running on fresh oil rather than an oily water mix lol
 
Oil change

Set me thinking.....

My car, well over 100 bhp/litre has an oil change each 18k miles, at a nominal 50 mph average that's 360 hrs.

Now my boat (50 bhp/litre) needs an oil change each season, say 40 hours. I think I will give it a miss this year !
 
I posted with the before winter brigade, but should have added that the boat remains in the water with the occasional use every few weeks just to enjoy some great winter days.
David
 
LOL, ok then, spill the beans, did you change the oil, or will you wait for recommissioning time? :)
 
MapisM said:
LOL, ok then, spill the beans, did you change the oil, or will you wait for recommissioning time? :)
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Yes I do the lot, oil change and all filters, anodes etc along with a coolant change if its not been done in the last 2 years.

Mind you all with newish volvos, read the latest MBY and andrew 38s story about VP dealers trying to extract servicing charges at the wrong hours just to cover the warranty that they should give in the first place!, well done andrew38, to be fair he did contact me about it but I coulnt give a honest answer as ive taken flack from a uk dealer once this year for giving help on matters that VP should have just plain and simply given warranty on there faulty products without any questions whatsoever.
 
volvopaul said:
Yes I do the lot, oil change and all filters, anodes etc along with a coolant change if its not been done in the last 2 years.
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Sounds sensible.
I'd be interested to hear also what's your take on the pros and cons of oil changes before or after winterization, if I may ask.
 
Oil does not become acidic as such, it protects from the normal acids which form in an engine from combustion, it dissipates them into the oil and generally they are burned off along with other deposits through the oil being at working temperature. Moisture is more of a problem, oil deteriorates naturally in an open environment, and to an extent it actually absorbs tine amounts of this moisture. With new oil you are better off because it offers more protection over winter, and for what it costs i always change it.
 
Why has nobody mentioned the engine manufacturers recommendations in the service manuals for oil changes or are these comics too? Personally I'm in the change oil before winter camp and have the old oil analysed because as spannerman says, it gives you the winter to sort any probs out.
Also, I would make a distinction between a high revving/high power engine in a planing boat and a low revving/low power plodder in a displacement boat. Somebody flame me if I'm wrong but isn't the oil running at a higher temp/pressure in the former than the latter and therefore require changing more often?
 
Mike, there are cleverer folk than me on here, but what you say is not necessarily true. While the oil may work harder in a planing boat, a "plodder" could take much longer to get up to temp, thereby suffering greater fuel wash issues, and the engine could suffer more wear as a result.
 
rafiki_ said:
Mike, there are cleverer folk than me on here, but what you say is not necessarily true. While the oil may work harder in a planing boat, a "plodder" could take much longer to get up to temp, thereby suffering greater fuel wash issues, and the engine could suffer more wear as a result.
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Take your point but what we are talking about is not how well the oil lubricates the engine but how long it remains in a condition in which it is capable of doing it's job of lubricating the engine. I'm happy to be corrected by wiser forumites but I'm guessing that must be a function of temp, pressure and total engine cycles
 
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