A different oil question

I read every post in the 17+ (at this time) page thread on synthetic vs. dino oil. Fascinating, and educational stuff there, and I'm not being sarcastic.

But I have a different question, that maybe you all could help with -- at the risk of starting another debate.

What are peoples' opinion on when to perform a normal annual oil change (as well as other maintenance items such as belts, filters, etc)?

We are in the Pacific Northwest, so our boat stays in the water year round, however my boat basically just sits in the marina from roughly October through February. I plan to add some cold-weather cruising amenities to reduce that time, but the fact is our boat usage drops dramatically in the winter, and probably will do so for a while.

So, I see generally two options 1) change at the end of the fall or 2) change at the beginning of spring.

If I change in the fall, the engine sits in clean new fluids all winter. Any time we take the boat out in cold conditions would be using the new product. And with no time commitments the task can be done when convenient.

But, if I change in the spring, then I know everything is new when I actually start to cruise. Boats sitting in our winters tend to grow into problems.

Does the lack of use of the newly changed items concern anyone else?

We change our oil and filters based on hours, not time. The FL120 manual calls for a 200 hour oil change interval. We change the lube oil and oil filter every 100-150 hours. The injection pump oil gets changed religiously every 50 hours per the book.

If a boat is going to be laid up for a season or more, like the boats many people haul for the winter in the Great Lakes and New England, it's a good idea to change the oil immediately before layup so the contaminants in the dirty oil can't attack the bearing surfaces and other components it's in contact with while the engines are just sitting.

The couple we boat with a lot don't use their boat in the winter as he's with FEMA and is usually away managing a disaster relief operation during much of that part of the year. He generally changes the oil and filter in his 420hp Cat at the start of their "off season" or if he's called away before he can do this he has it done.

But if you use your boat year round as we do, changing the oil and filter per the manual interval is the best thing to do. Some people change the oil but not the filter, changing it every two or three oil changes. To me that's totally counter- productive since all they're doing is leaving a quart or more of dirty oil in the engine when they do this.

Since compared to many other boating costs oil and filters are damn near free it makes no sense to me at all not to change both at the interval specced by the manufacturer. And if one chooses to change it more frequently, well, I've never had anyone in the engine manufacturing or service industries-- automotive, rail, aviation, or marine-- tell me that fresh oil is bad for an engine.

Best to change in the fall, and put a way clean as oil tends to come acidic. If we have not used the boat much, 20 hours, did an oil analyses to see if the oil should be changed. I usually have the oiled changed in the fall/winter. However oil should be change every 100 to 124 engine hours regardsless. For belts hoses they should be checked every year to cracking and make sure they are still soft, but as a general rule they should be change ever 7 to 10 years.

Phil Fill said:

Best to change in the fall, and put a way clean as oil tends to come acidic............

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That's the advice generally given in owners manuals and such and I agree with it.

Oil like good scotch does the body a service. The best thing to do is to follow the mfg instructions, and deduct hours depending on severity of use. If you are on a continous cruise running at the sweet RPM perhaps a change at 50 hours might be necessary. Regardless the longevity of engines are a direct result of timely, frequent lub changes.
The other issue is the start up after a period of long rest. You must find a way to circulate the oil before a firing. With gas not an issue, just take off the coil wire and crank the engine until oil pressure is obtained. With a diesel I am sure there is a way to do this as well. That way the engine has had its drink before it starts and will reduce the wear and tear. Bill. PS: donot forget the tranny/gear, it should be changed annually as well.

I think you can view boat diesels a bit like how we all saw car mileage intevals creep up as oil and engines got better.

I have mostly heard 100 or 200 on boat engines. I've always have been in the 200 hr camp and never had an issue even with 3000+ hr engines, both gas and diesel.

I think dropping down to the 100 hr interval if the engine has seen hard service or the oil looks/smells different than normal (though I am for the first time thinking about oil analysis)...a change could be warranted.

I think all engine layups should include an oil change...

Gear oils can go quite a bit longer as there are no combustion products in them...this is where syn oils really shine due to the nature of gearboxes. I have gone 2-3 years without changing gearbox oil even in commercial aplications with not noticeable damage/wear.

Cyclone said:

.......... The other issue is the start up after a period of long rest. You must find a way to circulate the oil before a firing. With gas not an issue, just take off the coil wire and crank the engine until oil pressure is obtained. With a diesel I am sure there is a way to do this as well. That way the engine has had its drink before it starts and will reduce the wear and tear. .

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Don't you think that if that was really necessary the manufacturers would have included a convenient way to do it and put it in the operating instructions?

There's such a thing as overthinking things.

If one believes that cranking a diesel over prior to firing it off is necessary so as to build oil pressure (I don't), with the old engines like the FL120 you can do this by simply pulling the fuel shutoff knobs up. The engine will crank but no fuel will be sent to the injectors.

Depending on the design of the exhaust system there may be a danger of filling the muffler with raw water that can then back up into the manifold and thus into a cylinder or two. Our fiberglass mufflers have petcocks at the bottom that can be opened to drain the mufflers or prevent them from filling under longer bouts of engine cranking, but we've never had to use them.

I don't believe pre-cranking an engine adds enough to the life of the engine to warrant the additional wear on the starter. The engine will crap out for some other reason long before the tiny bit of wear induced by starting the engine cold has any detrimental effect. As Ron said, if it was actually an issue the engine manufacturers would have made some provision for pre-pressurizing the oil system when they designed the engine.

"What are peoples' opinion on when to perform a normal annual oil change (as well as other maintenance items such as belts, filters, etc)?"

Why would "peoples opinion" matter when the folks that built the engine already published Their opinion?

OH yes so right!!, but then again some of us feel we can walk on water. I have found that those who read the manuals supplied are called "Nerds" and those who make that water walk are the ones who keep the economy going so we "Nerds" can have a comfortable existance. RTFQ. Read the "F" Question.

FF said:

"What are peoples' opinion on when to perform a normal annual oil change (as well as other maintenance items such as belts, filters, etc)?"

Why would "peoples opinion" matter when the folks that built the engine already published Their opinion?

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Fair enough question, but my owners manual simply states every 100 hours or annually, whichever comes first.

I figure annually is more likely with our boating usage, so I was just wondering "when, if annually?"

mattkab said:

Fair enough question, but my owners manual simply states every 100 hours or annually, whichever comes first.

I figure annually is more likely with our boating usage, so I was just wondering "when, if annually?"

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Best before it sit' idle for any length of time.

Matt: The annual date for most is just before lift out onto the hard. For you folk in warmer areas, set your own date, but most likely just before US Thanksgiving so that when Easter rolls around you have fresh oil for the next season. Bill.

I have noticed that my DD 8.2's start to use a bit of oil as they approach 95 - 100 hrs use. Basic thinking, perhaps, on my part, but I look on that indicator as a sign the oil is ready for change. We change at 100 hrs +/-, filters are changed as well. Oil samples are done annually, & final change of the season is done just before haul out. So far so good.

I change oil, filters & clean the centrifugal filter between 100 hrs & 120 hrs on the Hinos. The boat stays in the water year round but isn't used during Jan. or Feb. & limited use in Dec. or Mar. I have pan heaters on the mains & gen. to keep the oil warm, I use them during the summer as well.

Follow the builder's manual for maintenance of your engine.

I did it all this past weekend. We, generally use our boat year-round-ish and doing it in the Spring make me feel more optimistic that boating season is coming. And that's good enough for me.

Re changing just prior to layup does anyone just pump out the old oil out and not put any back in? Perhaps oil in the crankcase helps to prevent condensation. Or ther's the danger of someone starting the engine w no oil but it would seem that could be prevented. Seems such a waste to put new oil in .... let it sit all winter and then throwing it away. Any opinions? We could do facts later. Or a mix like we usually do.

manyboats said:

Re changing just prior to layup does anyone just pump out the old oil out and not put any back in? Perhaps oil in the crankcase helps to prevent condensation. Or ther's the danger of someone starting the engine w no oil but it would seem that could be prevented. Seems such a waste to put new oil in .... let it sit all winter and then throwing it away. Any opinions? We could do facts later. Or a mix like we usually do.

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I drain the old oil, add the new oil, then start the engine and run it for a few minutes so new oil is distributed throughout the engine.

This is standard practice, what you would find in the manual, a textbook, or be taught in auto shop class.

I don't see any advantage to your suggestion and I see several disadvantages to it. Oil doesn't go bad sitting in the engine. It's running the engine that causes it to need to be replaced on a regular basis..

Ron: The new oil circulated until eng get to temp should be left in over the winter and then used over the next season. None running of the engine does not contaminate the oil. Bill.

Ron and Cyclone,
I think the oil does "degrade" over the winter chemically and can possibly cause etching of metal parts. Otherwise why is it typically done? But I've only heard and read that this is the case.

Oil doesn't degrade in 6 months or so otherwise buying in bulk would kill mainas, fleet operators, etc...etc...

The engine may pick up moisture...but it will whether empty, new oil, or old oil.

Old oil may have ph problems and may etch...new will not...unless you get a LOT of water in it or something else happens.

99 percent of the boats I know of around me do it in the fall...only a handfull do it again in the spring.

Wouldn't all the oil be completely back in the pan in a matter of hours? What good does new or old do in there? How many surfaces will it adhere to for the entire winter to provide protection? Would changing the oil and then running it for a little while clean enough of the contaminants off from the previous oil to do any good whatsoever?

I, of course, could be wrong, but I will again, I come back to my synth oil point I made in the other thread, and that point is that my 80's Perkins is a big and stout lump of engine designed for more abuse and life than I will every give it. Even IF etching was happening, would it really affect engine longevity? Especially since I am probably changing oil more often than recommended.

I am not being argumentative, I am honestly trying to understand why these apparent Brahma Bulls of the engine world need to be treated like kittens?

Tom-

Yes etching is bad...especially year after year...

No...some oil stays at least microscopically I guess...that's why thicker dino oils have a better rep for long term storage...even better is a "fogging oil".

yes...yes....and yes..to the other questions

But you are probably correct as it won't matter a hill of beans for the average winterized engine.

Mobil Oil agrees as that was their recommendation to one Q&A...that fall or spring was OK with them...

Like many discussions here...it may be minutia compared to a lot of other things that may be hurting your engine over the life you own it.

But if the choice...I pick fall layup over changing in the spring.

If you really want to do it right..like FF always goes back to...there are long term layup procedures for machinery that have to be better than the just let them sit with new/old oil in them.

manyboats said:

Seems such a waste to put new oil in .... let it sit all winter and then throwing it away. Any opinions? We could do facts later. Or a mix like we usually do.

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I've never heard of anyone changing the oil before a winter layup and then changing it again prior to using the boat in the spring/summer. The only reason to change before layup is to prevent contaminated oil from sitting in the engine and on the bearings and such all winter.

As Ron said, clean oil doesn't go bad just sitting there so there is no reason at all to change the new oil out in the spring. You just start up and go boating until it's time for the next winter layup at which point you change the oil prior to the layup.

Except DD expects an unsealed engine to allow condensation to drip water into the oil passages all the out of service months.

Might make sense to fog the engine then seal it up.

I agree with those who change before winter, then use that the following season. I suspect you've thrown away a lot of good oil, Eric...sorry...oh, and one other thing. Your idea of changing the oil more often than the filter. Where did that come from? Does not compute for mine. In fact a case could be made for changing the filter once halfway through the season keeping the same oil, in view of the fact that the solid contaminants are filtered out in the filter, and it makes sense to remove it, rather than put clean oil in to run through a contaminated filter, just sayin'...

HaHa This is funny.
We all have our own ideas.
But it's not my idea that oil breaks down and becomes undesirable by spring. I've just heard that many times.
And Peter I've never stored a boat through the winter so never thrown out good oil for that reason but changing every 50 to 70 hours I probably throw away good oil that way. Perhaps one of the local TF members would want to get it from me and run it another 50 to 70 hours?
Being single weight that may be an advantage.
This winter is the only winter I've stored a boat and I do intend to throw away the oil ... unless I find that what I recall that I've heard and read is false.
But if I didn't throw away good oil I'd have to throw away bad oil. And if I threw away bad oil that would mean I'd have been running bad oil in my engine.
No I'll stick to changing my 30 weight oil frequently.

manyboats said:

Being single weight that may be an advantage.

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What is your married weight advantage?

Single weight is the advantage unless your'e paying taxes.

Proper answer would involve TC.