Mercury 60 ELPT oil question

[stcif]

Yesterday I bought a used 2013 Crestliner Fishhawk 1600. It has the Mercury 60 hp ELPT four stroke on it. Prior to buying it I did some research as to recommended oil and read that many use a 25W40.
When I picked it up I spoke with the tech who went over the boat with me. I asked him what oil they used. He said they put 10W30 in everything.
As he was explaining why they use 10W30 (because it gets cold here in NY) I noticed a sticker on the top of the engine. It shows Mercury recommends 10W30 from zero to 40 degrees Fahrenheit. It then recommends a 25W40 from zero though and above 40. I basically will use this boat from late April through October.
I think I am going to dump this oil soon. The question now is do I go with a 25W40 Quicksilver oil or an HDEO like Rotella 15W40? Does Quicksilver have additives a marine engine needs that Rotella doesn't?
The excuses the tech had for using 10W30 were weak at best. Especially since there was a sticker on the engine explaining that 25W40 can be used during cold weather. Thanks for any advice.

 

[BigCahuna]

If the motor can use 10/30 when it's below 40, I can't see how using a 15/40 wt would hurt anything. I'm sure you will have some cold mornings during the months you'll be using the boat. And Rotella is a heavy duty oil that works in diesel motors and people use it in motorcycle motors where it's run thru the motor, transmission, and to cool and lubricate the clutch.It's tough stuff. The anti wear additives in oils are the same, if you look thru the VOA'S or UOA"S. Just different levels by brand. Do you know what wt oil is in the motor now?.I would run Rotella if I had to do a change right now.,,

 

[Phishin]

I'd stick with an HDEO oil in a 40 weight.

If you want to run dino, anything that reads 15w40 is good....many recommend Rotella, Delo, or Delvac.

All three of these dino HDEO's also come in a synthetic version, and their weights will be 5w40. Run any with confidence.

 

[bubbatime]

Lots and lots of people run regular 15W40 with great success. That is what I would run too. Most people average less than 50 hours a year on their boat engines, and 15W40 will definitely hold up just fine over a 50 hour yearly run.

I agree that the tech's argument for 10W30 are weak. Probably just use it because they can get it cheap and it surely isn't a HDEO and doesn't meet most manufactures specs which is doing a great disservice to their customers.

 

[stcif]

Thanks everyone for the replies. I'm guessing they are using some bulk 10W30. Probably not even Quicksilver as he mentioned.

 

[sweezy722]

I have owned the same engine since Feb 2011. I have asked a lot of questions to marine mechanics, and also asked the Marine Doctor on his forum. I have used Amsoil WCF but have come back to Quicksilver synthetic blend 25w-40. You may be fine running a lighter oil but at this time I will not do so.

That 60hp motor will sit at 6000 rpm under max load for and hour at a time. It works harder than any engine I own.

I sent quicksilver synthetic blend to blackstone. Virgin Quicksilver synthetic blend oil starts as a very strong 40 weight and in 20 hours is a middle of the road 30 weight. Amsoil with the 4.6 HTHS sheared just a little more than the Quicksilver. If you start with a lower oil I am guessing it will shear even lower.

An oil change with 25w-40 cost $30-35 depending on where I buy the supplies and do it myself. An oil change with any of the cheaper oils will still cost me around $20.

Boating is very expensive and I am not trying to save $15 per year on oil. Good luck and you will love the motor.

 

[stcif]

Thanks sweezy. Good info. I am taking the boat out tomorrow for pike opener. After that I am changing the oil out.