Synthetic Oil in I/O

Jerry

Wonder if that's the same GPS he uses to set his trim?

LOL!

I have an easier method:

1. Drive boat to dealership.

2. Tell servicewriter to winterize boat and motor, wash and wax boat, and shrinkwrap entire package. Batteries are removed and stored indoors.

3. Store rig at back of dealer's huge fenced lot.

4. Mail the bill to me.

Deal performs service competently, changes oil and filter, checks for any warranty items, takes care of, et cetera.

In the spring, about two weeks before I want the boat, I call the dealer and say:

"Recommission."

-- Skipper

Jerry

It could provide better protection in severe service or extended storage.

5W-30 would be adequate, 15W-40 too. I've used both in our antique inboard.

Rob

There has been quite a discussion about whether Quicksilver oil is multi-viscosity or not. The following speaks for itself:

Quicksilver 4-Cycle marine engine lubricant is a specially blended oil which is intended for use in our MerCruiser products. This is not an off the shelf automotive tvpe lubricant but is specially formulated to incorporate the features needed to satisfy the unique operating environment of marine products.

Quicksilver oil is classified as a 25W40 multiviscosity lubricant. The multiviscosity properties are obtained by blending very special base stocks eliminating the need for the synthetic polymers commonly used to give automotive lubricants their multiviscosity properties. Quicksilver oil is a Newtonian fluid which means that the viscosity does not change with the rate of flow. Automotive oils using a synthetic polymer to make a 10 weight base oil have the added viscometric properties of a 30 or 40 weight oil are called non-Newtonian fluids. The viscosity does tend to change with flow rate due to the "shearing" or breaking apart of the long "strands" of the polymer. There are some polymers which experience permanent shear loss resulting in a subsequent change in viscosity.

Mercruiser products are designed to operate at very high speeds and loads when compared to a passenger car. These extreme operating conditions can shear the polymers used in some automotive oils. The result is a dramatic loss in oil pressure and potential engine damage.

To eliminate this problem and still provide a lubricant capable of being used throughout a range of operating temperatures and conditions. Quicksilver 25W40 is formulated without any polymers. The requirements of a marine lubricant extend beyond the need to penform well at high speeds and loads. Extended periods of idle or trolling create the need for the oil to continue to function even when diluted with fuel and moisture. Quicksilver 25W40 has a unique "marine" additive package to deal with the potential problems caused by these operating conditions. Some of the polymers used in multiviscosity oils are hygroscopic (water gathering) and form a light brown emulsion usually observed in the crankcase breather areas. The marine environment, being very "wet" tends to accentuate this problem. Emulsified polymer is no longer available to help the 10 weight base oil maintain 30 or 40 weight properties.

-- Skipper

I suppose if you are trying to "fake" being Skipper, there are many of his cut and pastes moldering around, like this one. Which was posted a dozen times by Skipper in his attempt to show he knew something about boats.

Actually, it's a over exaggeration of the terms Newtonian and non-Newtonian fluids.

Non-Newtonian fluids do use shear force to enforce a change in viscosity - just like Newtonian fluids. What did he say?

Take my word for it - shear is a mathematical term to describe linear mapping and is very useful in chemical compounding.

Back to the real world.

The difference is in how the shear is applied to change viscosity - in a Newtonian fluid it's applied in a linear fashion while a non-Newtonian fluid is evolved in a non-linear fashion.

The end result is that they both act in the same fashion, do the same things and are described in the same way.

The other little secret is this - the automotive oils apply the shear differently, the lubricant properties are exactly the same as Quicksilver's "Newtonian" brand.

Also be aware that any oil that has been compounded to a particular "standard" has to perform to the standard - thus, oil compounded to a 25-40 standard is the same as any other oil compounded to a 24-40 standard, Newtonian or non-Newtonian.

In my opinion, rather than pay the price of Mercruiser Quicksilver, use a good premium heavy duty oil like a 15-40 diesel or even a straight 30 weight SAE.

According to Mercury, they mix a SAE 25 and SAE 40 oil and call it a 25W40 oil. There is ABSOLUTELY NOTHING concerning the formulation or rating of oils that makes THE LEAST sense in this as relates to a multi-viscosity oil. The 25W oil rating has nearly nothing to do with viscosity.

Take two base stocks, say, SAE 25 and SAE 40, mix them together and you have some single weight oil with a viscosity of something between SAE 25 and SAE 40. You do NOT have a 25W40 oil.

The only significant bit of information in the article is that single weight oils are not subject to the failure of viscosity improvers and, thus, may offer more protection than synthetic oils.

Sometimes, you just gotta wonder.

You haven't done either, because you know this is the real deal. You have gotten your wish.

"Harry Krause" <harry.krause@gmail.com> wrote in message