Mercury Oil

[juggernaut1]

I was looking into which oil to use for Mercruisers and happen to come across this article written in Sept 2015 in relation to the Mercury 25W-40 oil and thought it may be of interest to those of you running Mercruisers.

http://www.boatingmag.com/how-marine-oil-made

The article suggests that the Mercury oil has a new formulation:

.......new oil retains 99 percent of its original viscosity through its service life

Mercury says its new additive package offers 33 percent more wear protection and features a new corrosion inhibitor.


The above was confirmed during my discussion with a Merc tech recently as he commented that several owners were reporting reduced oil consumption with the new Merc oil. Possibly do to the improved viscosity over the life of the oil as mentioned above?

And a comment on the differences between the dino and synthetic blend.

There are two versions of the Mercury 25W-40 formula, the standard and the synthetic blend. Both have the same additive package, but the synthetic blend has synthetic base stock and is thus more durable in extreme conditions..........


Other interesting comments on the weighting of the oil

A multiviscosity oil, like the Merc 25W-40, behaves like a 25-weight oil when it’s cold but has the protection of a 40-weight oil when it’s hot.

Mercury settled on the 25W-40 viscosity range because “that’s where the protection is,

Edit - Confirmation of the new formulation

https://www.boats.com/reviews/mercury-introduces-new-four-stroke-oils/


And further

http://boatingindustry.com/news/201...new-lineup-of-four-stroke-marine-engine-oils/


Interesting from the above link:

In high-temperature shear stability testing the oil proved to be 40 percent stronger than the next best marine oil


Tech Oil Article:

http://www.repairfaq.org/filipg/AUTO/F_oil_facts.html

 

[paulswagelock]

Lots of marketing hype in there. It is a fine oil, and will provide adequate lubrication.

 

[juggernaut1]

I realise a completely different application (60HP outboard) but interesting nonetheless. The Merc oil in the second column is the new blend - fourth column is the old blend. New Merc blend looks one of the better oils? Fuel in the Delo is higher than the others.

Any comments on the comparison?

http://www.bobistheoilguy.com/forum...03/Outboard_oil_analysis_4_stroke#Post3833803

 

[juggernaut1]

Scott - what differences/improvements have you noticed?

 

[paulswagelock]

In the end, all four oils yielded the same results. The only difference is how much lighter his wallet was with each one. Delo is $12/ gallon, Merc is $8/qt and Amsoil is $10/ qt.
they each have a different combination of detergents and high pressure wear additives, but in the end, they all worked fine.

Hence my post above, it is fine, but nothing spectacular. I ran a comparison with Delo, Delvac and Merc brand in my last boat with a 350 mag. On that engine, the Merc had the poorest results, but they were close enough that it didn't really make a difference.

 

[Quint4]

What difference do you notice? Short of tearing the engine completely apart and taking high def photos/ measurements, then reassembling it and running it for a year then dis-assembling it again for inspection.

Now repeat this for each oil on identical engines ran under exactly the same conditions / rpm ranges and report findings.

 

[juggernaut1]

Paul,

Similar price ranking in Oz but the pricing is higher - for example Amsoil Marine 10-40 is AUD$19.50 per quart on-line and is hard to come buy. Merc blend is approx AUD$12.40 quart online or a little more at my local chandlery but easy to come by and Delo is the lowest.

 

[juggernaut1]

What difference do you notice? Short of tearing the engine completely apart and taking high def photos/ measurements, then reassembling it and running it for a year then dis-assembling it again for inspection.

Now repeat this for each oil on identical engines ran under exactly the same conditions / rpm ranges and report findings.

I rang a few Merc techs re this exact point - they advised the motor is going to fail from other causes before it will wear out due to oil choice.

 

[eweise]

I used to use Mercury full synthetic in my engines....when they discontinued it, I switched to AMSoil and haven't looked back.

Ditto on the Amsoil

 

[scoflaw]

mobile 1 full synthetic 15- 50 , doesn't use a drop all season.

 

[juggernaut1]

Just noticed that Amsoil has now brought out a 25/40 synthetic blend oil to go head to head with the Mercury offering.

Spec sheets are here. I've also included the spec sheets for the full synthetic marine oils for comparison. Of note is that the viscosity of the blend is higher, has a higher HTHS and a lower Noack volatility compared to the full synthetics. TBN and the wear test is the same as the full synthetic 10/40. Overall - looks like a good oil and I would expect to be cheaper than the full synthetic.

http://www.thebestoil.com/wp-conten...gine-Oil-Product-Data-Bulletin-G3418-5-16.pdf

https://www.amsoil.com/lit/databulletins/g2133.pdf


Marketing:

http://www.oildepot.ca/amsoil-releases-new-25w-40-oil-for-mercury-marine-engines/

 

[tony357]

I use penn grade 1 in my boats and race boats.. I had issues with mobile one in the race boat it foamed up too much and would lose oil pressure above 6000 rpm. I tried several fixes but having the crankshaft in the oild from the 14deg angle just beat the oil too much and had to use a crude grade oil. I use to run Valvoline off road use only race oil until it was discontinued the replacement was vr-1 which did not have enough zinc additives for flat tappet cam. I then through research mostly my cam grinder switched to penn grade 1 4 years now and no issues.
http://www.penngrade.com/penngrade-1/

 

[juggernaut1]

I think I will stick with the AMSoil 10w40. Let's not forget that for several years, Mercury produced a full synthetic oil that they recommended for the 8.1, so for them to later come back and suggest that it is made to run on a semi-synthetic rather than full synthetic is a load of crap, IMHO, of course. At any rate, I'll stick with full synthetic.

Not trying to change anyone's preferences - just posting that Amsoil has good alternative to the Merc equivalent. But given Amsoil has taken a "step back" and made a semisyn suggests the takeup of the full synthetic hasn't been widely accepted by the boating community for whatever reasons.

 

[juggernaut1]

I use penn grade 1 in my boats and race boats.. I had issues with mobile one in the race boat it foamed up too much and would lose oil pressure above 6000 rpm. I tried several fixes but having the crankshaft in the oild from the 14deg angle just beat the oil too much and had to use a crude grade oil. I use to run Valvoline off road use only race oil until it was discontinued the replacement was vr-1 which did not have enough zinc additives for flat tappet cam. I then through research mostly my cam grinder switched to penn grade 1 4 years now and no issues.
http://www.penngrade.com/penngrade-1/

Not a fan of Mobil 1 myself although I do use it in the wife's Toyota Aurion for tootling around. I used to use Mobil 1 in a turbocharged street car I used to track and it sheared badly - very low oil pressure at idle at the end of each session. I switched to Motul 300V after having the motor rebuilt/modified and spun it to 8,000 rpm every time I took it out without issue for the last 8 years (sold it last weekend). I use Castrol Edge 0W/40 in my daily turbo'd car without issue.

Brother also tried Mobil 1 in in his LS2 powered car after it was twin turbo'd and the gauge would drop back to nothing at idle after it warmed up! He switched to Castrol Edge 10w/60 before it cost him an engine.

 

[juggernaut1]

But I see what Amsoil has done, they've essentially put a guarantee on a box.

There's a guarantee on the full synthetic 10W-40 box too isn't there?