Fluid Changes for Winterizing, Do I Need to?

[zellerj]

if you did not use the boat at all (zero starts)

then leave it.

however if you started the motor even once......



then the acids start building up in the motor. these acids are a byproduct of combustion. the first thing they attack is the soft metal in the bearings

an oil change is cheaper than pulling a motor to rebuild it.

The duty cycle between oil changes in a large diesel is 25,000 miles, and if the engine is tight so blow by of exhaust gases into the sump is minimal, this can be stretched to 50,000 miles.

If your Mercruiser engine(s) are in good shape with minimal blow by, I think you are wasting your time, money and effort. Check your dip stick, if the oil looks the same as when you put it in, it does not need changing. If the color is black, consider changing it, because black oil indicates contamination by exhaust gases.

New oil formulations are designed to run a lot longer between changes than they used to be.

 

[dingbat]

Not under Australian consumer law. Companies have been (successfully) taken to court over latent production defects in all sorts of products (including cars and boats). If the product does not perform or last as long as 'a reasonable person would expect', the courts will find in favour of the consumer, every time. But if your engine fails after 5 years, and you haven't done oil changes, the courts are going to laugh in your face...

Here's a prefect example of what I'm talking about... (slightly different issue than an engine, but vehicle out of 'warranty', and the courts still hung LDV out to dry, and rightly so!)

Rigby v LDV Automotive Pty Ltd [2021] QCAT 316 - Caselaw

Rigby v LDV Automotive Pty Ltd [2021] QCAT 316 | Queensland Civil and Administrative Tribunal Caselaw.

www.queenslandjudgments.com.au

This is up my alley….25 years of international contract and warranty negotiation experience under my belt.

The US has similar warranty provisions under the Magniso-Moss Warranty Act.

Problem is….there are so many “loop holes” you could drive a truck through them. All I can say is beware of anything in CAPS in a contract or warranty Terms and Condition

Paragraph 17….. Judgement based on seller’s negligence to advise…not on the buyers failure to perform.

Obviously a poorly written warranty clause from the sellers perspective. Nobody in their right mind offers a “life time” warranty w/o conditions or waiving or restricting consequential and incidental damages as a condition of warranty.

This would appear to be the equivalent of US small claims court. Good luck getting a major Corp into small claims court. You couldn’t afford it.

 

[Lou C]

I don’t think a once a year oil change should stress anyone out; keep in mind older carbed engines run cool and rich therefore fuel dilution of the oil is a real issue and this has also been a problem on modern 4 stroke outboards. Despite up to date fuel and ignition systems they run very cool like 125-135. On a modern inboard with closed cooling at least these can get to 160-180 warm enough to burn off any condensation and fuel contamination. I do the boat once a year every year even if I put very few hrs on it. On our two older Jeep’s that only get driven 1500-4000 miles a year once a year change. Other cars in our family that get driven more every 6 months/6,000 miles with syn oil.

PS
When I had the heads off 4 years ago due to blown head gaskets even though there was water in the oil there was virtually no sludge build up anywhere and at the time the engine was 29 years old. So there you have it.

 

[Lou C]

This is up my alley….25 years of international contract and warranty negotiation experience under my belt.

The US has similar warranty provisions under the Magniso-Moss Warranty Act.

Problem is….there are so many “loop holes” you could drive a truck through them. All I can say is beware of anything in CAPS in a contract or warranty Terms and Condition

Paragraph 17….. Judgement based on seller’s negligence to advise…not on the buyers failure to perform.

Obviously a poorly written warranty clause from the sellers perspective. Nobody in their right mind offers a “life time” warranty w/o conditions or waiving or restricting consequential and incidental damages as a condition of warranty.

This would appear to be the equivalent of US small claims court. Good luck getting a major Corp into small claims court. You couldn’t afford it.

Very interesing here we have the lemon law, they get 4 tries to fix a problem but there is some interpretation, in that the defect must impair function in some way, so things like minor blemishes or squeaks and rattles don't qualify but water leaks that cause rust, operational problems that affect reliability and safety, in most cases would.
Back to the issue at hand, if Mercruiser says to change the oil minimum 1x per year under most use, then a 'reasonable' person should do that, if you really want proof of how often you should do it, you can always do an oil analysis which will tell the tale, of how much fuel dilution there is, water from condensation, did the oil lose viscosity, etc. I did this 2x on my old engine, just curious, and found that the Merc 25/40 oil held its viscosity as well as a straight weight, and before the head gaskets blew, I was getting elevated sodium levels in the oil (salt water cooling) so I knew something was up, related to a previous overheat. I did not have fuel dilution though, might be because OMC specified the 160 stat even in salt water which lets it run a little warmer. On that topic, when I pulled off the heads I did not find evidence of salt or calcium clogging any cooling ports, as is sometimes reported, and a justification for the lower temp stats used in raw water cooling in the salt.

 

[AShipShow]

Holy crap... I started a "whats the best oil" thread... sorry everyone... a bit ironic as I reply at a sprint car race where they replace engines after almost every race... im tending towards the better safe than sorry camp.. mostly cuz i took college Chem 3 times to pass.. moral of the story.. do what you want.. I'll at least change the motor oil.. gonna keep the filter

 

[Cortes100]

I do agree on changing the engine oil before winter storage even though it had low hour usage. Once per year.

What I don't understand on why to change the gear case fluid every year. How is it different than a truck, you don't change the diff fluid for years and thousands of miles. The truck is exposed to water, salt, dirt, temps from +30C to -40C.
If water can't enter, the lube doesn't go bad. On the last 2 Merc Alpha drives I've owned from new, I'd drain a few ounces of gear lube. If it looked good, put the plug back in and top up to the full mark. Been doing that for years.
Seems like a waste of perfectly good oil. Am I missing something?

 

[Kubaat3lover]

But for pressure drive you have to drain the lube, same for impeller change..
what do you think to drain to clean container then refill with same oil?
I have same issue, drive ran only 10 hrs , fresh fluid and now i have to change it..

 

[Drcoffee]

I do agree on changing the engine oil before winter storage even though it had low hour usage. Once per year.

What I don't understand on why to change the gear case fluid every year. How is it different than a truck, you don't change the diff fluid for years and thousands of miles. The truck is exposed to water, salt, dirt, temps from +30C to -40C.
If water can't enter, the lube doesn't go bad. On the last 2 Merc Alpha drives I've owned from new, I'd drain a few ounces of gear lube. If it looked good, put the plug back in and top up to the full mark. Been doing that for years.
Seems like a waste of perfectly good oil. Am I missing something?

if you actually submerged your differential in deep water ( not rain water) then you really should change the gear lube more often. Water can get in the vent which is normally a 1” stub vent with a rubber seal on the pumpkin or thru the the axle seals. When you dunk the hot differential in cold water the rapid cooling will cause the diff to suck in water. Similarly, The outdrive is submerged constantly in water. Nothing ruins gears faster than water Exposure.

in my truck, I run a 3/8” hose from the differential up to behind the gas filler with a breather so even deep water wont get into the differential. Some boat ramps are a shallow grade and I could be up to the bumper when launching and submerge the axle.

 

[Lou C]

If you really put just a few hrs on it you can remove the drain and see what comes out. If its pure gear oil then its probably fine to keep running it but any sign of moisture its worth the $20 to replace 2 qts of gear lube.

 

[2550SX]

I have a 2002 Chevy 2500 silverado with the 8.1 and I bought it new. I dont drive it every day but I I do drive it a lot. I managed to put 168,XXX miles in it so far and it seems to run fine. I don't change the oil every night. Which means it has had acid in the oil for 19 years now. I do use Mobile 1 and I believed the oil is engineered to combat acid. My guess would be that it more depends on the oil you use. That old straight 30 quakerstate can you have in your garage from the Eisenhower administration probably does not have an anti-acid package engineered into it. Your fine. Enjoy boating next season.

 

[CayugaCobalt]

I wouldnt sweat it, especially if you are not going out to sea and not running WOT all day long; some of the "annual must change" rules only apply for sea going vessels. For example, you MUST replace your impeller every season. Not True. I have experienced several summers of very limited use and have not and will not again waste good oil to fulfill some "rule". They way in which I use mine, I have noted no detriment. Its a 1997 7.4LX MPI.

 

[Scott Danforth]

Holy crap... I started a "whats the best oil" thread... sorry everyone...

LOL

 

[AShipShow]

I'm not here to call anyone out for being wrong... But there is a lot of "information" being thrown around here without any sources...
Unfortunately this is how bad info gets propagated.
If anyone has actual useful info to show that "new fangled" oil is better I'd be interested to read it...

I know wiki can be a little iffy on its accuracy, but some interesting info here...
Motor Oil Wiki Page

 

[Scott Danforth]

sources...

Mahle symposium on bearing failure due to acid buildup - compression ignited and spark ignited motors. about 2006 or 2007 held at Cummins CMEP (Cummins Mid-range Engine Plant)