Hydrocruiser

I just bought a new Ford SUV...I sucked out a sample and sent it in for analysis...the oil in the engine from the factory was conventional 5W-20...had no anti-wear or anti-friction agents in it...it definately is a "break-in oil".

I believe in a break-in period before going synthetic in offshore boats and feel that 40 hours is about the right interval. Using Kendall 40wt would be my choice or of course the Mercury product.

After 40 hours or roughly 2 oil changes...it's time for a high ZDDP synthetic oil to assure long life and excellent performance.

vandeano

Thats not a bad idea. I use to use M-1 20W-50 V-Twin. But I figured I would play it safe and run the Mercruiser oil for warranty reasons. So just and case something went wrong I could at least say "its your oil"

Hydrocruiser

In actuality in talking with Mercury they indicated that the only true oil related failures they see from time to time are from uneducated do it yourself boaters using a totally incorrect product or procedure such as:

-Non-detergent/non-additive oils that cost a buck a quart.

-Oil that is in the wrong viscosity range such as a 5W-20.

-Not checking the oil and running way below correct levels or overfilling and windage.

-Sludge from not changing the oil.

-Oil pump or line failures and system failures and addition of aftermarket products that failed.

Mercury does not do oil analysis to determine what brand is in the crankcase. The Magneson Moss Act forbids them to mandate what brand of oil you use (unless they provide it at no charge to you for life) or to inflict damages upon you for using another brand. So they recommend in their manual or if you call and ask that you use an equivalent to 25W-40 which is mostly a 40wt oil blended with 25% 25wt...so in essence it is a "37wt" oil. My opinion..a conventional blend oil such as 25W-40 is just plain stupid. I think you can safely round off to a 40wt. Now the additives in Kendall and Castrol 40wt oils are the same as Mercs.

If you think using their product will afford you protection in the event things go wrong...it won't.

FYI...Mercury told me they have never seen an oil related engine failure specifically related to use of synthetic blends or synthetic oils.

They will eventually have their own brand of synthetics as they are negotiating a deal with a provider much as Volvo-Penta has.

Remember...Mercury is NOT in the oil business...there is little profit in it for them and they know that "we" know where to get Mobil-1 and Amsoil. Mercury's Racing Teams usually have cases of 20W-50 Amsoil Severe Service Racing Oil in their transportation vehicles.


Remember...the same oil Merc says to use in a 4 cyliner 120 HP engine is what they tell you to use in the 1075's.

Sterling uses 15W-50 M-1 in their engines after much testing..that says a lot I think.

vandeano

Very good info. I'll change back to the M-1 after Im sure this engine is broken in. I have about 10 hrs so far. So maybe another 30 hrs. then I should be OK

Hydrocruiser

20-40 hours should be all that is needed for the engine to settle in. Break-in is usually best if you avoid excessive idling...long wot intervals...or short jaunts.

Best is cruise with a good run for 10 minutes initially they say and build up from there as you head towards 20-40 hrs.

Hydrocruiser

Thought I would share this recent experience.

My brother has a Pantera 24' with a highly modified 454 putting out about 550 HP.

His oil pressures were too low with 15W-50 M1 so he tried Mecr 25W-40 and they were about the same after a good run.
His previous experience with M-1 20W-50 was pressures were too high. I don't have the exact numbers.

So I had him try a 50/50 mixture of M-1 20W-50 V-Twin with
M-1 MX4T 10W-40 Motorcycle oil because it is the exact formulation as V-twin but a lesser viscosity.

The mixture probably yielded an overall viscosity equivalent to a beefy 40wt.

The pressures are great now...and both oils have a ZDDP level of 1800ppm which is the highest you can get.

This would probably be what I will use in my next offshore boat...please let those options hit the strike price...

Mobil told me that mixing these two oils is logical as the base and additives are equivalent.

What do you guys think?

minxguy

The chemistries in both of the formulations are probally the same. I am pretty positive that Mobil wouldn't change additive packages on different viscosities, hell they own Infinum. You would have no problem with the blending of two different viscosities, what you end up with takes more than a guess. You need to know the viscosity of each oil at 210 F, know what percentage of each "flavor" is going into the mix, and then graph it on a two componet blending chart. then and only then will be able to say "I have a heavy 40 or a light 50" Not real heavy science but protocol non the less. Ken

minxguy

The Magneson-Moss act does forbid the mandate of OEM products but it is only for the duration of the warranty, not for life. As far as Mercury recommending a 25w-40, it's not that stupid. A 25w-40 will offer faster oil pressure than a straight 40 on start up in cooler mornings, (I am sure that there are boaters in the Northern part of the States who boat in April) and a 25w-40 being a multi-viscosity still needs polymer to be added to the blend. As we know polymer sheaing is one of the major causes of viscosity loss. With such a short viscosity spred from heavier basestocks and less polymer there is less shearing so the stay in grade performance is better. And because it is a 25w-40, it will have the same viscositiy as a SAE 40 at 210. But, and a big but, at temps above 210F the 25w-40 will thin less than the SAE 40 therefore offering better film strength than the straight weight. This is due to the polymers that were added to the formula to produce the multi-viscosity charatristics in the first place. Ken

Hydrocruiser

A 25wt is still a hard cranking cold start oil in many parts of the country depending on ambient temp. It is a blend not an actual multi-vis..so it's more a straight 37wt oil they told me.
Supposedly they say no polymers added.

minxguy

A 25w is still "thinner" than a SAE 40 at any ambient temp. Probably not by much but it still will be thinner because it does meet a "w" specification where the SAE 40 does not. I would imagine that somewhere around 10-15 degrees above zero the SAE basically becomes a "candle" and stops pouring where as the 25w40 will continue to pour to 0 because it meets the w classification. If it were not a multi viscosity, Mercury could not label the bottle as a 25w-40. It would have to be labeled an SAE 40. As far as no polymers.........are they using a 40wt base stock and a pour point depressant to achieve the low side performance? If the Mercury oil was a straight "37wt" which by the way is just a number, there is no SAE viscosity spec for 37wt , how does Mercury get the oil to a 40 grade? You can't call a heavy 30 (which a 37 wt would have to be called) without adding some sort of viscosity improver or a blending in a heavier basestock. Ken