Timing

[Gabor15908]

Talking about changing oil and fuel filters....what is the thinking about this?
At the beginning of the season say April , May or at the end of the season October, November? I like to do all this at the end of the season but I see some of my neighbors at the marine like to start the season with "fresh" fluids in the engine in spring.

 

[dlochner]

The theory behind the fall oil change is to reduce the time old, perhaps slightly acidic, oil sits in the oil pan. The oil in the engine is nice and clean, hopefully, not degrading the metals in the engine.

I used to follow this routine. Reading the owner's manual for the engine revealed a recommendation of an oil change every 100 or so hours. 100 hours in a car at 60 mph is about every 6000 miles, a number that sounds reasonable.

Reviewing my engine hours I saw that I was running the engine for 50 or fewer hours a season. I now change the oil every other season and at the end of the season so the really spent oil is not sitting in the oil pan all winter.

 

[bawlmer]

This has been the subject of many threads and the consensus is that you change your oil at the end of the season so your engine sits over the winter with fresh oil in it. Some folks (including me) change it twice at the end of the season to insure the oil is definitely clean. That would be your choice of course.

 

[capta]

We do our lube oil filters (ME & genset) about every 150 hours, which is about twice as often as the manufacturer recommends. However, we are full-time liveaboards and a charter boat, so these tools are essential for our lives and livelihood.
We did get over 19,000 hours out of our last genset and it was a running take out when we changed it out, so I don't mind the added expense of a few extra filters and some oil.
As for clean oil sitting in an engine for an extended period of non-usage, I do not consider that any advantage. As a professional captain, I would change my truck's oil immediately when I got back to town and began using it, so if I had a seasonal boat I would probably change the oil at the beginning of the season rather than the end.

 

[DArcy]

I change my oil every spring just after launch. I just like the idea of fresh oil in the spring. Similar to Dave above, I only run the engine about 50 hours a year so the concern with old oil sitting in the pan over the winter doesn't really concern me; it's just not that old.

 

[NYSail]

I’m a fall changing guy....... like to put to bed clean to get acidic oil out.

Greg

 

[Gunni]

End of season, prior to mothballing. Acidic and water-emulsified oil doesn’t just just sit in the oil pan, it bathes and clings to bearing journals and gear surfaces. Fresh oil coats everything with a full compliment of anti-corrosives and wear additives - which go right to work when I twist the key in the spring.

 

[jon hansen]

i agree with gunni's logic.

it is what i was taught.

fresh oil before putting the boat away is what i do

 

[Davidasailor26]

One more vote for end of season changes. I do it because I was taught it's better to get the combustion byproducts out rather than letting them sit. I don't see how there could be any real advantage to letting it sit. It's not like the fresh oil is going to go bad sitting in the pan for the winter. Also, once the weather warms up, would you rather be sailing or changing oil? In the fall you need to winterize anyway, so the oil change is just one more maintenance task while you have everything opened up. In the spring I just turn the key and go sailing.

 

[NotCook]

Used to change every fall, before layup, or every 100 hours, whichever comes first. Now, it is just annually or 100 hours, whichever comes first. Oil and filter are a small price to pay to keep an engine running for a long time.

Here's what I don't understand about the price of engine oil. When petroleum was in the range of $100 a barrel, motor oil could be had for $9.99 a gallon (Rotella T SAE 30, for example). Then, when the price of petroleum dropped to the $50 a barrel range, now oil is routinely $20-24 a gallon. What's up with that? Makes a fella want to go "hmmm"...

 

[jssailem]

Be careful @NotCook it is a slippery road you are treading on. From a man of wonder “hmmmm”
to a Conspiracy Theorist.

 

[Rick486]

Used to change every fall, before layup, or every 100 hours, whichever comes first. Now, it is just annually or 100 hours, whichever comes first. Oil and filter are a small price to pay to keep an engine running for a long time.

Here's what I don't understand about the price of engine oil. When petroleum was in the range of $100 a barrel, motor oil could be had for $9.99 a gallon (Rotella T SAE 30, for example). Then, when the price of petroleum dropped to the $50 a barrel range, now oil is routinely $20-24 a gallon. What's up with that? Makes a fella want to go "hmmm"...

I would hazard a guess that the producers of lubricating oil have discovered that the demand for their product is inelastic, meaning they can raise the price and the consumption does not change very much. On the other hand, demand for gasoline has historically been quite elastic. Price goes up, consumption goes down. So the producers try to squeeze profits out of the lube market. Just a guess.....

 

[sailme88]

At the end of the season you should change your oil for 2 very good reasons. First, you rid your engine oil of the contaminates that it has consumed during the season. Second is moisture. Simply said your oil pan collects moisture in the form of condensate. The mere event of heating up when running and cooling down creates condensate. Get rid of it !