Change Oil Fall or Spring

[Cadence]

Originally Posted by upstateny

Obviously I live in the North East. Worst case it can get down to -20F.

I have an IRWIN 30 with 16HP Kubota diesel. Is it better to change the oil in FALL when I put the boat on land or in the SPRING when she goes back in the water?

Previous owner changed oil both FALL and SPRING. The last two years I have been changing the oil in the FALL. I also wonder if the answer changes when you are further south.

I believe the previous owner had some wisdom. What does a few qts of oil cost, throw in a filter.

[TBear60]

Well, you've heard the entire gamut of opinions. And they're all right.

However, if it doesn't cost you anything extra to do so, I would recommend putting up your boat with fresh oil. While the old "myth" (if you believe it or not) of the acid in the old oil damaging (or not) your motor's internals may be debunked with newer blended/hybrid/synthetic oils; it is most prudent to change in the fall and not take the risk (risk is never certain) of damaging your motor. While the "damage" that may occur is probably very slight, if you're one of those who will keep the boat/motor for 10+ years, changing it in the fall will certainly help prolong the peak performance of the motor.

To put this in context, storing your boat/motor for 4 months of every year for ten years, means your motor sat idle for 40 months of it's life; more than 3 years (one third of it's life)! Sit a diesel for 3 years and you'll have to do an entire overhaul before using it again.

Ask any diesel mechanic, one of the biggest killers of a diesel motor is not running it, ie putting it in storage for 4 months in the winter (the other killer being bad lubrication, ie not changing the oil on time).

So storing the motor with new oil might be the cheapest investment to saving your motor! Good luck!

[Bargain Bill]

Don't bother changing - - the oil will get you through the next season.

[rslifkin]

Originally Posted by TBear60

Sit a diesel for 3 years and you'll have to do an entire overhaul before using it again.

That's BS. If it's properly stored, it'll be fine after 3 years. I've seen diesels stored for 3 years and after being put back into service and given some quick prep, they fired right up on the first crank and ran like they'd last run yesterday.

[OBT]

Having been in charge of a fleet of very expensive diesel engines during my career and having been through several engine educational workshops - change your engine in the fall and store it with fresh oil. I would never leave the old oil in for the winter. If those who dispute this info wish to extend their oil change schedule, fine. Good luck to them. Not my problem.

[Cheechako]

Fall, so the acids created in combustion don't sit on the bearings etc all winter with no engine heat up. But, I thinks it's a very minimal problem....

[Shrew]

Originally Posted by Cheechako

Fall, so the acids created in combustion don't sit on the bearings etc all winter with no engine heat up. But, I thinks it's a very minimal problem....

This is one of the two reasons I was told to do it in the fall.

The other was water. As it was explained to me, the water will sit on the bottom and oil doesn't circulate through the dipstick tube. The only easy way to tell if you have water in the oil is to drain the oil and let it settle and look.

You don't want the acid in the used oil sitting long term and you don't want water in there long term either. So, it is safest to do an oil change before the boat is laid up for any length of time.

How much of this is truth vs wives tale?? Who cares, it needs to be either in the fall or the spring. I've never heard a good reason to wait until spring.

[Heathenly Twins]

I would do both, why let your engine sit in contaminants? Then, as you said, in the spring change it again because of the moisture etc. It's a 16hp so not that much oil to begin with. If cost is a concern I bet you could source a decent bulk purchase.

[upstateny]

Many thanks for all the posts. I think I will be changing the oil before I pull her out of of the water. Thanks again everyone.



BTW- This year I only day sailed on the Hudson River due to COVID-19. I doubt I put more than 15 hours on the motor this year. I wonder how many others sailed close to home and put less than 20 hours on the motor this year.

[Compass790]

Originally Posted by upstateny

Many thanks for all the posts. I think I will be changing the oil before I pull her out of of the water. Thanks again everyone.



BTW- This year I only day sailed on the Hudson River due to COVID-19. I doubt I put more than 15 hours on the motor this year. I wonder how many others sailed close to home and put less than 20 hours on the motor this year.

I'd take your old oil & use it to do my 150hr oil change if I was next door & do my next one at 135 hrs. You are throwing away perfectly good oil but it's yours to throw away.

[David B]

Originally Posted by upstateny

Obviously I live in the North East. Worst case it can get down to -20F.

I have an IRWIN 30 with 16HP Kubota diesel. Is it better to change the oil in FALL when I put the boat on land or in the SPRING when she goes back in the water?

Previous owner changed oil both FALL and SPRING. The last two years I have been changing the oil in the FALL. I also wonder if the answer changes when you are further south.

Fall - clean oil, without contaminants (including acids) for your engine during the rest period. Why leave the engine sitting with dirty oil all that time.

[flyingfin]

Never change oil then immediately layup a motor. If you decide to change oil before hauling in the fall, make sure you put at least one hour run time on the new oil and filter. We have had customers (or their "marine mechanic buddy") drain the oil and refill crankcase after being placed on the hard. Piston rings stuck because top end had very little oil residue. And dont forget to fog the engine just as they haul you. Run engine hard and spray engine fog into the air intake until the engine dies from lack of oxygen!

[rslifkin]

Running the engine to circulate the new oil is good, but it doesn't taken an hour. For me, the process is to change the oil (with a short run to confirm to filter leaks), then the night before haulout, warm up the engines, move the boat to the lift pit, then winterize and fog the engines.

That's it for the season, then in the spring I change the spark plugs before launch (gas engines) and once we hit the water, open the seacocks, bleed the air out of the strainers, check fluids, and if all is well, they should start right up (and if any time-consuming issues are found at the last minute and I'm not the last launch of the day, ask the marina nicely to tow me the 300 feet to my slip).

[S/V Illusion]

The few marine engine experts I know advise fogging a diesel is useless.

[BlackHeron]

Originally Posted by S/V Illusion

Myths die hard. It makes no difference.
Most sailors put less than 200 hours on every year.

200 hours barely gets us up the East Coast in one seasonal migration. What is this winter layup thing anyhow? I thought this was "cruisers" forum, not couchsailors forum.