I have a new 236 with a Mag 350 MPI - question on oil changes

Danishgod

I am approaching 15 hours with a 2013 Mag 350 MPI.  I was in to see the dealer on another matter and I asked him when I should change the oil.  I assumed he would say that I should bring it in after 20 hours, the break in period.

I was a bit surprised by the response - "it is not a bid deal to run it for the summer - say 35-40 hours and then we can change the oil - no issues."

So forum members, do you have an opinion on this matter?  Oil change now or wait until the summer is over?

Michael T

@ 06 Rinker270 I think many jurisdictions started mandating catalytic converters around 2011. Also different engine sizes were phased-in at different times. If I remember correctly the EPA started with the big (regular production) engines first. So I don't think you were anywhere near the mandated time lines unless you lived in Calif. - even then I don't think they were required in 2006.

I don't know US laws but I believe 100% that your boat can be sold anywhere in the US as a grandfathered manufactured boat. I don't know if it can get into Europe without a CE sticker as I don't know how far they reach back for the CE requirements.

I know in Canada it was as of 2013. I had to have catalytic converters on my 2014 502 magnums.

You can easily tell if you have a cat converter. Just look at your exhaust headers. The first cats (first two years?) were 3 brick units that were real big. After that Mercury went to a 1 brick model that was smaller, cheaper and easier to maintain. Those are on my 2014 EC 360.

As for mid season oil changes - it depends on how long and how hard you use your engines.

*****If you boat from April to November and put 100 hours on your engine then I'd change the oil and filter at 50 hours. If you boated for less months or only put around  50 hours on your engine then I'd just replace the oil filter at mid season and just top up the oil.

Remember I am maintenance obsessed...but I have followed that schedule with every I/O engine I have owned for 25 years and every one of them is still on the water and none of them have had rebuilds.

In extreme uses I have changed the oil more frequently. I have changed the oil and filter on a ski boat after a weekend of constant skiing by my friends and I. I have changed the oil and filter on my high performance engines after one hard run....but that's extreme.

But, back to YOU - if YOU follow the schedule above see *****your engines will, IMO, love you and demonstrate that by remaining in excellent health.

chamberb

Minimum every fall and every 50 hours during the summer. Again that is a minimum, you may wish to change it more often. 

Michael T

I disagree with your dealer! Absolutely!

I would change the oil and filters at 25 hours maximum. That's enough time for the break-in oil/factory oil to allow the rings to seat. I still believe in that.

At 25 hours I would switch to Mercruiser  semi synthetic oil because I believe you have an engine with a catalytic converters and the semi synthetic is better for the cat than full synthetic. In fact Mercury specially formulated the semi-synthetic for its cat equipped engines.

IMO synthetic oil is far superior to oils with just a little synthetic in them. I prefer the Mercruiser brand, particularly for new Mercruiser engines.

At about 50 hours I would either change the oil and filters again or if you are only half way through your boating time I'd remove the filters and replace them with new ones and top up the oil.

I only use Mercruiser High Efficicency oil filters as they have special filter media and anti drain back check valves. They also retain more volume than many brands.

You will get a lot of advice, maybe some conflicting.

Do this and your 350 mag will last forever.

I have owned 5 brand new 350 Mags and followed the above procedures with them.

I keep in touch with previous owners, who have followed that service pattern - all of the engines are still in excellent health and will be, and - IMO - far longer than many other owners' 350 Mags.

BTW I did that with my 2014 set of twin 502 Mags.

That is my opinion.

Congratulations on your purchase!

Danishgod

if my engine does not have catalytic converters, it is 2013, then can I assume that synthetic is still fine in the engines?  I cant seem to get a handle on this issue.  I am sure it is not a big deal, but just checking.

Danishgod

is it possible to change the oil filter and not the oil mid season or is it a big mess to do this?  I am new to this so forgive my elementary questions.

Michael T

Yes, if I had non-catalytic engines I would at least run semi synthetic. If I could get full synthetic (it's the same price or sometimes less) I'd use it. Make sure you use the weight recommended by Mercury to maintain your warranty. I believe its 25W50 but check YOUR manual for YOUR engine.

I found it very easy to just change the oil filter and oil mid season. I wrapped an old towel around the base of the oil filter attachment/post and had a couple of rags handy and two plastic bags. I unscrewed the oil filter after I let it drain down and quickly slid a plastic bag under it. Then I double bagged it and took it to a local garage for disposal - later. The old towel caught any drips and I used the rags just to clean up the area. Never had a mess in the engine bay, hardly even a drip of oil on a valve cover. I did kick over an oil filter once on the cockpit floor - nasty!. LOL .....after that I double bagged the filters right in the engine bay.

Then its just an oil top up. So new oil filter and some fresh oil at the mid season point- this was recommended to me by a guy who was the best race engine (marine and auto) in the area. Did it with all of my boats for the last 25 years.

All engines still in excellent condition!

06Rinker270

@Danishgod congrats on the new boat.  As you can tell lots of good advice from the people on here with years of experience.  Dont be afraid to ask the "elementary questions" everyone here has been there and is very helpful.  

Sorry to hijack but a quick question regarding catalytic converts@"Michael T" What year did Merc start adding cats?  I have a 2006 350.

Also do you still recommend mid season oil changes on older engines?   

06Rinker270

As always thanks for the info @Michael T.  I might go ahead and change it again.

MarkB

20 hour oil change, and then you need to pull and do a 50 hour service on engine and drives ... like check drive alignment, etc. according to Mercury break in procedure.