Oil change and end of season

[LindMark]

I've always heard its best to not let old oil sit all winter. I'm really not sure that matters. Time for oil change but season is wrapping up. Should I change oil now and then not worry about it or go over by 5-10 hours and change before winter? PCM 343. Thanks.

[kylant]

go over, then change for winter

[bturner]

Depends on how OCD you are with you're boat and if you want to follow best practices/manufacture's recommendations. Will changing the oil next season or going 5 - 10 hours really hurt your boat? With today's oils and a good quality filter (which is really more important these days than the oil) probably not. Is it a good idea? Well..... probably not. I mean if you're going down this road why just go 5 - 10 hours over and do say 10 - 20 or go big and just change the oil every other season? A bit dramatic I know but you get the meaning, slippery slope type of thing, right? The smart move is always to follow the maintenance schedule whenever possible.

The bottom line is it's you're boat and the decision to either maintain it properly or not is purely up to you. And as Chris Rock once said "You can drive your car with your feet too but it doesn't make it a good idea." Just because you don't have to follow best practices doesn't make it a good idea either.

But that's just me, who knows I could be completely wrong.

[LindMark]

I guess OCD would say change it now and then change it again in 5 hours so it sits all winter with fresh oil. Seems a little extreme so I was just wondering what the lesser of two evils would be. I tend to think it would be better to go over then change it as apposed to change it now and don't worry about changing it next year until it is time.

[scottb7]

My opinion is that at 50 hours oil change - which i do - these boats are very over maintained, as people said based on the quality of the oil, and the 50 hour standard never having changed.

I would also say that in my opinion no one would live long enough, or use their boat enough, or ever know if leaving old oil in their boat wore out their engine prematurely or had any effect.

What i do, is stick to the 50 oil change schedule and I don't worry about how many hours are on the oil at the end of the season, I leave the used oil in....

[bturner]

Or split the decision. Change the oil but leave the filter. Buy a good filter (I like Wix, GM, NAPPA Gold, K&N but there are a bunch of others out there), dump the oil and just refresh what's in the pan. 15W40 is super cheap even for the full synthetic. While on the going overboard topic I started using the Rotella full synthetic this year. 4 quarts at Wally World is $20.....

https://www.walmart.com/ip/Shell-Rot...llon/869812640

[H2O]

Just for your information, that particular Rotella 15w-40 is Not certified for Spark Ignition (gas) engines. It would have SN or SM rating besides CK4. Does it matter? I don't know. I have been using Royal Purple 15w-40 (#04154) which this year is not API certified SN and it was last year with the same part number!

[bturner]

I believe that would be a true statement of any 15w40 oil by definition right? I mean if you look at the Shell write up on the standard Rotella it never mentions spark engines, doesn't carry the SN rating and that was the oil that was specifically called out for by Indmar engine in my last boat. 15W40 in general is Diesel oil with only a couple manufactures calling it anything other than that with the exception of Royal Purple and Amsoil. Not arguing with you or disputing your point but.....

There's a good article (that's probably more of an ad) on the Amsoil site that's pretty good about diesel in combustion engines here.....

https://rotella.shell.com/en_us/prod...rotection.html

The whole oil thing, especially when you get to using synthetics can pretty much get saints to argue. The whole 15W40 thing has had me wondering for years why this spec came about. I would assume it's due to the duty cycle and possible blow by based on the duty cycle marine engines see but it's always left me wondering why they would spec a diesel oil instead of a full synthetic.

Your point on the Royal Purple SN rating isn't lost on me either as I agree with everything you've stated. I'd be willing to bet that API certifications cost a pretty penny and companies are only going to spend the money to certify products that are going to be sold primarily in certain market to segments. I mean how many other sectors are using a 15W40 spec for their engines other than diesel? So, if your certification is about to expire and you have to make the decision to do both CK, SN or both certifications, which are you going to spend your money on for a product that almost exclusively sells to a diesel market?

So I guess my closing thoughts would be..... If using an oil recommended by the manufacture that doesn't carry the SN spec is okay in non synthetic oil, how can using the synthetic blend or full synthetic oil from the same manufacture that states that it exceeds the standards of the non synthetic oil be any worse?

And here we are full circle again with the oil discussion.

[kylant]

do you really think 5 hours is going to make a difference??

do you change your car oil exactly at the 3K, 5K, 10K (whatever your interval is) mark and not go over by any mileage? doubt it

[Skidave]

I used to have a 2002 Saturn SL2 for commuting to work (100 miles a day). It burned a bit of oil. When I changed the boat oil, I would use it to top off the Saturn. People cringed at this, but the used boat oil was nothing like used car oil. Low hours, no emission junk, low engine operating temps, etc.

I found the fuel to be more of an issue than oil. And forget spark plugs. I tried everything. The best were the style with the iridium tip. For 6 years, I filled up at the same gas station and calculated my mileage at every fill up (87 octane).

Winter: 38 mpg
Summer: 42 mpg using AC

They put a blend of some garbage in the winter and mileage suffered.

Great car for its intended purpose. One water pump, one coil pack failure, one exhaust hanger, plugs once a year with a throttle body cleaning, tires and brakes as needed. My wife snapped a half-shaft backing out of the driveway one time - odd.

I sold it with 265K miles.

Sent from my SM-J337V using Tapatalk

[bturner]

do you really think 5 hours is going to make a difference??

do you change your car oil exactly at the 3K, 5K, 10K (whatever your interval is) mark and not go over by any mileage? doubt it

On my cars I do 7K oil changes with Mobile 1 and Wix XP filters and rotate the tires at the same time. If I do go over it's only by a 100 miles or so at the most, typically I'll do it before I hit 7K. Then again I'm on time to parties, dentist/doctor appointments and that kind of stuff too. I never have a problem moving my used cars, boats and such as friends and relatives know how I take care of my stuff and will buy them from me most times before I list them when I'm ready to move on. I have yet to actually list something that the first person to show up to look at it hasn't bought.

Everyone is different, has different priorities and will take care of their possessions differently. This is just how I am and it seems to have worked out for me over the years.

[killerrkyle]

It is unequivocally a waste of time and money to change oil after 5hrs, regardless of how long it will be laid up.

[shag]

Inserts 'eating popcorn' meme

[bturner]

I think Scott said it best when he stated that these boats are way over maintained. The maintenance schedule assumes the worst (as it should) and most likely errors on the conservative side on oil life to ensure it's getting changed regularly. I mean look at the conversions here and opposing views......

Where I see the concern is the slippery slope aspect of the conversation. The stated interval is 50 hours and we're looking at extending that 5 - 10 hours which works out to 10% - 20% over the recommendation right? I mean if you're good with 10% over, why not 20%? You could also continue you to play this game and say screw the maintenance schedule, it's been proven that new oils last for 2x - 3x times longer as they're being changed so why not only change it once a season (which BTW I've known several people over the years say is their practice and actually do it this way). In all honesty I think you'd probably be good here as well.

The example I suggested about doing something in the middle and changing the oil but not the filter is something I actually did this year on my jet ski. We put 4 hours on it this season due to the incredibility crappy start to summer we had that effectively pushed the start of our summer back to July. On the Jet ski I couldn't see replacing a K&N filter that only had 4 hours of use. To be truthful I believe the oil was fine as well but for the 10 minutes and $10 it took me to swap it out, I did so pretty much on principle, not need.

If you don't want to swap yours out, I get it, don't. I wouldn't call you out for it or criticize your decision because in all honesty I can clearly see your point. Like wise I can see the other side of it too just from the OCD perspective. But in that context who would you rather buy a boat or car from?

In the end it's your boat to do with as you see fit.