How often do you change the oil?

[rauch0812]

Being new boat owners (of an older boat)... how often do you change the oil? It's a I/O 5.0L Merc with 172 hours on it (if any of that makes a difference)... the dealer changed the oil when we purchased it and we've taken it out twice putting 11 hours on it. Someone said to me "you should change the oil soon"... what? Are you kidding? How often do you have to do that? And what oil is recommended?

Thanks,
Des

 

[Philster]

Re: How often do you change the oil?

You are overdue!!!! 10 hours max!!!!!!!!!!



Once per season. At the end. So it doesn't sit with water in it (even as a byproduct of combustion) and contaminants all winter long.

Sort of depends on amount of use it gets, but here where boating is May through September, it is hard to put that many hours that you need a change mid-season.

Also, don't confuse advice around different fluids. I will tell you this: If the dealer changed the engine oil 11 hours ago, you are good for the season. BUT, if the outdrive GEAR LUBE was not changed, then holy smokes, I'd drain that sucker and replace it with Merc High Performance Synthetic yesterday.

Don't mix drive lubes. If you don't know what is in the drive, drain it now (and replace it, of course!)

Buying a use vehicle, especially a boat, pretty much requires you drain and replace all the fluids. The only exceptions would be if you were already familiar with the boat (you were the mechanic, or you REALLY trust a relative or friend who owned it).

 

[642mx]

Re: How often do you change the oil?

100 hours or once a year... whichever comes first. Same with the drive fluid.

 

[Fireman431]

Re: How often do you change the oil?

Every 100 hours without fail. Also check to see if the fuel filter (if equipped) has been changed. If you don't have one, I recommend installing one.

 

[bomar76]

Re: How often do you change the oil?

I go no more than 50 hours, and at the end of the season.
But then again I use the boat a little harder than most on here.

 

[rbh]

Re: How often do you change the oil?

Last year we logged less than 50 hours on the engines, I will not change oil till this fall.
If there is any condinsation in the pan or galleries it will be gone in an hour of running.

 

[Fordiesel69]

Re: How often do you change the oil?

Honestly you will need to send a sample into blackstone labs to be sampled before you can know for certain. Suck some thru the dipstick and send it for a sample mid way thru the season.

I say this becuase you need to address these following areas:

-Fuel dillution
-Water/Coolant contamination
-Holding its viscosity SAE30 will stay a 30wt if used correctly. If not it may fall to a 20wt.

Technically it should last all season and still come out semi transparent. If it gets thin or jet black, then it is overfuling. Boats will tend to use oil moreso than a car being under more load all the time. Make certain to top off if need be.

 

[rauch0812]

Re: How often do you change the oil?

Being new boat owners this forum is pricesless! Ok - so we're good on the oil. We also check it before we go out everytime (only being twice) and it still looks new.

We did notice the power steering fluid was low, we were just going to add more to the reservoir? Can I use fluid from an auto store or do I need to buy marine? I see quick silver power trim & steering fluid online...?

The gear lube we are going to drain completely and refill... (thank you philster) Does anyone have an opinion on Quicksilver High Performance Gear Lube?

Any other fluids we should be checking or replacing?

Desera

 

[redone4x4]

Re: How often do you change the oil?

i change engine oil and outdrive oil at the beginning of every season, before the first trip. I use only synthetics since i want it to last as long as possible.

 

[QC]

Re: How often do you change the oil?

I just read a couple of manuals. Volvo says once a season, no reference to hours which seems stupid as the manual does not appear to be pleasure craft only . . .

Mercruiser says 100 hours or annually.

Four cycle OBs are too numerous to discuss, and two cycles, well " if you need to ask" . . .

My point is that this thread has not identified which product we're talking about, and this is an engine topic (doesn't belong here). Let's leave these discussions to the individual engine sections please, as it gets waaaay too confusing when you mix up technologies and manufacturers.

Also, DonS gets credit for what I think is the only way to think about this topic. If you are not going to follow the manual, then this is just a matter of opinion and simply decide which alternative you want to go with. There may be plenty of reasons that the manufacturer may be wrong, but once you deviate you have determined that you are smarter than they are, so simply go for it.

 

[rauch0812]

Re: How often do you change the oil?

When you say "don't mix the gear lubes" since we don't know what brand is already in there, simply draining the oil lube out (including the reservoir) and refilling with new lube is what you mean, right? There would still be residue from the old oil...?
Desera

P.S. bought the boat used, don't HAVE a manual, thought forum would help. Don't claim to be "smarter" than manual, as a matter of fact I think I've made it clear in all my posts I'm a new boat owner who doesn't have a clue... therefore I bring EVERYTHING to the forum for help =)

As a matter of fact, would never have even thought to change the gear lube before Phils friendly post! Thank you again everyone who's offered advice - I'LL TAKE ALL I CAN GET!

 

[QC]

Re: How often do you change the oil?

Hey Desera,

Don't take my comments in any way other than they're intended:

1) reminding all that we try to keep this section free of engine topics

2) That the manual is really the best source although I completely understand the need to discuss and the benefits of that.

I am an old OEM guy, as are some of the other technical mainstays here. I don't follow all OEM guidelines, that's for sure, but it is important to delineate what are actual factory recommendations and opinion. That's all.

I have a .pdf copy of the owners manual. PM me with your email address and I'll send it to you

 

[642mx]

Re: How often do you change the oil?

When you say "don't mix the gear lubes" since we don't know what brand is already in there, simply draining the oil lube out (including the reservoir) and refilling with new lube is what you mean, right? There would still be residue from the old oil...?
Desera

You'll still have a little fluid left in the drive, but its not enough to be concerned with. Just change it with some high quality lube (I use the Merc brand) and you'll be fine.

P.S. bought the boat used, don't HAVE a manual, thought forum would help. Don't claim to be "smarter" than manual, as a matter of fact I think I've made it clear in all my posts I'm a new boat owner who doesn't have a clue... therefore I bring EVERYTHING to the forum for help =)

99% of the people on this forum was in the same 'boat' as yourself at some point. Thats why we join forums to gain knowledge and pass out useful tips we've learned. Don't let anybody discourage you from posting questions.

 

[642mx]

Re: How often do you change the oil?

1) reminding all that we try to keep this section free of engine topics

QC- would it not be easier to move the thread to the proper forum and then post a friendly reminder of why you did it? Keep in mind, we where all newbies at some point.

 

[Philster]

Re: How often do you change the oil?

Drain drive gear lube.

You should read up on how to do this, but essentially you remove the bottom drive plug, and the top one.

The top vents the internals so the fluid is pushed out via gravity and natural air pressure.

To refill, use Merc High Perf synthetic gear lube. You need a pump, which is designed to fit onto a gear lube bottle, and you add the gear lube by pumping it into the bottom hole until it oozes out the top/vent hole.

I forget the specifics on dealing with the reservoir inside the boat. The directions are on the web.

You don't have to get in there and lick the gears clean! Just drain it.

 

[QC]

Re: How often do you change the oil?

QC- would it not be easier to move the thread to the proper forum and then post a friendly reminder of why you did it? Keep in mind, we where all newbies at some point.

Maybe so, but I am thinking these need to be very specific and that it had run it's course. I am not chastising anyone. Moving was obviously one option, but these threads often don't do well even in the proper section. That was my point about opinion, but I understand the possibility that those comments stifle good debate. I am truly on the fence when it comes to this topic, it's almost general boating and almost I/O repairs . . .

He does have the manual now.

Edit: I just re-read my posts . . . I apologize if my comments seemed cold or rude. I never intend for that. Actually, I am usually posting with a smile on my face and trying to get a chuckle. As is obvious by my rambling and even contradictory posts, like I mention above, on the fence as to moving this particular thread and decided to make my internal debate public

 

[rauch0812]

Re: How often do you change the oil?

"she" does have the manual now, I appreciate you sending it over QC. I admit, I'm so far out of my element I didn't even realize this was an engine topic.

Philster, I searched changing the lower gear lube on the internet and found a helpful video, looks like we can handle it. If not for this forum it's likely I would have found out too late to change the gear oil. We went down to the marine store and picked up 3 quarts of Quicksilver High Performance Lube like the manual QC sent over to me stated. It did not say synthetic, I purchased just what it said, so I hope I went the right direction on that.

Thanks all!
Desera

 

[rauch0812]

Other Fluids?

Other Fluids?

How about power steering fluid or trim pump fluid? Should those ever be completely replaced or do you just check the levels regularly?

Thanks,
Des

 

[QC]

Re: Other Fluids?

Re: Other Fluids?

I just top off those ^^^^^

High Performance is synthetic

 

[rauch0812]

Re: How often do you change the oil?

Ha ha... that's funny. I searched and searched for synthetic quicksilver and fretted over whether to follow the manual like you suggested or all the advice on synthetic in the forum. Same thing... ha.