: ZDP Right ? Bad ?



Stoneage_Caddy
03-17-05, 03:41 PM
Bunch of college kids are at it again :

Oil Additives Bad For Aluminum Blocks?

A team of chemists and mathematicians at the University of Western Ontario deduced that most oil additives are complicated compounds containing zinc and phosphate. They then used computer simulations to find out what happens "at a molecular level when a film of oil containing additives is compressed between two hot, hard surfaces" like engine parts. They concluded that as the pressure rises, the molecules of zinc and phosphate form cross-links with each other, according to a science report in The Washington Post. In engines of steel alloys, this process helps minimize wear. But not so in aluminum engines, where the cross-linked molecular hash becomes harder than the metal and abrades the aluminum surfaces. In other words, if these guys are right, additives are good for engines with steel parts but potentially harmful if used in engines with major aluminum parts, especially on wear surfaces. Experts at the American Petroleum Institute told TheCarConnection they were not familiar with the Ontario study. -Mike Davis


http://www.thecarconnection.com/index.asp?article=8302

what do you think bob ? more snake oil scare tactitcs ? or have the kids been celebrateing St Patricks day early ? :drinker

dtyo
03-17-05, 04:54 PM
OK, I'm not Bob, but in my IMO, this is way off base. As far as I know, there are no aluminum bearing surfaces. Any bearing surface is steel to steel - the crank and cams sit on bearing surfaces - at least in most of the engines I'm familar with - Northstars may be different (but I doubt it)...?? Even in the case of an aluminum piston, it rides in a steel cylinder, and I'm not sure that could be considered a "bearing" interface/surface.


Dan

mcowden
03-17-05, 05:45 PM
In general, additives are not good things to use, especially not Teflon particulate additives. "ZMax," et al. may in and of themselves be good for friction properties, but when you add them to oil, which is a carefully engineered balance and blend of base oils and additives that perform specific functions, you throw off the balance of things like antifoaming additives and you wind up with oil that theoretically, and at low speeds, reduces friction, but at normal speeds and especially high speeds and pressures such as those found in modern engines, foams up and causes more problems that it solves. Whether or not these guys know what they're talking about is not what I'm commenting on. They might be absolutely right, but I'm with dtyo when he comments that there aren't many aluminum to aluminum junctions that would be subject to the conditions they're describing. That's my humble opinion. Your mileage may vary.

BeelzeBob
03-17-05, 08:47 PM
Reads like an April Fool joke......

I really get worried when "The Washington Post" starts publishing information on engines. The only worse thing would be The New York Times starting to do car evaluations....LOL

The article is talking about the standard oil additive package, the ZDP that is put in oil for anti-wear protection, not oil additives like the aftermarket stuff (Z-Max, Slick 50, etc...). The standard oil anti-wear additive is called ZDP and has both zinc and phosphate. All oil has this as there is simply nothing better at preventing wear and the GM EOS has a lot of extra ZDP in it for extra wear protection for assembly lube and breakin lube.

There are no "...two hot, hard surfaces like engine parts...." that are both aluminum in an engine....so the whole idea is pointless..... The wear surfaces are steel in case they forgot.....

There are several holes in the theory of what they are proposing.....

One, an "aluminum" engine has the same operating or wear surfaces as a cast iron engine...i.e...the crank journals are steel in both cases and the crank operates against the bearing inserts that separate the crank journal from the aluminum of the block. So....where is this area that the "...cross-linked molecular hash becomes harder than the metal and abrades the aluminum surfaces...." It doesn't exist...there is no aluminum to aluminum surface....so what is their point..??

The engine bearings currently in use are all aluminum surfaced...have been for many years. The old lead/babbit bearing surfaces are out of favor due to the limitations of using lead (environmental) and the need for higher strength bearing surfaces. So....regardless of whether it is an "aluminum engine" or a "cast iron" engine the steel main and rod journals of the crankshaft are running against an aluminum surface of the bearing face....and it works fine with ZDP. If the problem they are imagining were to really happen within the confines of the crank to aluminum bearing face it would surely eat up the bearings in no time.

The only conceivable place that a layman might suspect aluminum against aluminum in an engine is the aluminum piston against the cylinder wall of an aluminum block. But....this doesn't happen either. Aluminum will not wear against aluminum in an application like that so the cylinder bore is always either a cast iron insert (like the Northstar) or a coated bore (like Nikasil) or , in the case of a Reynolds 390 aluminum block with high silicon (a la Vega, Mercedes, Porsche, BMW, etc...) the piston is iron plated so as to prevent aluminum-to-aluminum contact.

Interestingly....a simple Briggs and Stratton engine (there must be millions and millions of them slaving away) has an aluminum bore and an aluminum piston since it is a cost effective way to make a limited use engine with low output yet it seems to run fine with ZDP in the oil and the more ZDP the better.....

I would give those "students" a failing grade, make them dissassemble an engine to find out what is in it and fire the Washington Post for publishing the drivel. They only did it, I'm sure, because it smacked of sensationalism if it were to be true then they could be the ones with the scoop.

"Experts at the American Petroleum Institute told TheCarConnection they were not familiar with the Ontario study."......yea, right. They were probably choking back their laughter which is why they were "not familiar with it.."

Pjs
03-18-05, 07:51 AM
Reads like an April Fool joke......

I really get worried when "The Washington Post" starts publishing information on engines. The only worse thing would be The New York Times starting to do car evaluations....LOL

LMAO.. :histeric:

Stoneage_Caddy
03-20-05, 02:30 PM
Reads like an April Fool joke......

I really get worried when "The Washington Post" starts publishing information on engines. The only worse thing would be The New York Times starting to do car evaluations....LOL

The article is talking about the standard oil additive package, the ZDP that is put in oil for anti-wear protection, not oil additives like the aftermarket stuff (Z-Max, Slick 50, etc...). The standard oil anti-wear additive is called ZDP and has both zinc and phosphate. All oil has this as there is simply nothing better at preventing wear and the GM EOS has a lot of extra ZDP in it for extra wear protection for assembly lube and breakin lube.

There are no "...two hot, hard surfaces like engine parts...." that are both aluminum in an engine....so the whole idea is pointless..... The wear surfaces are steel in case they forgot.....

There are several holes in the theory of what they are proposing.....

One, an "aluminum" engine has the same operating or wear surfaces as a cast iron engine...i.e...the crank journals are steel in both cases and the crank operates against the bearing inserts that separate the crank journal from the aluminum of the block. So....where is this area that the "...cross-linked molecular hash becomes harder than the metal and abrades the aluminum surfaces...." It doesn't exist...there is no aluminum to aluminum surface....so what is their point..??

The engine bearings currently in use are all aluminum surfaced...have been for many years. The old lead/babbit bearing surfaces are out of favor due to the limitations of using lead (environmental) and the need for higher strength bearing surfaces. So....regardless of whether it is an "aluminum engine" or a "cast iron" engine the steel main and rod journals of the crankshaft are running against an aluminum surface of the bearing face....and it works fine with ZDP. If the problem they are imagining were to really happen within the confines of the crank to aluminum bearing face it would surely eat up the bearings in no time.

The only conceivable place that a layman might suspect aluminum against aluminum in an engine is the aluminum piston against the cylinder wall of an aluminum block. But....this doesn't happen either. Aluminum will not wear against aluminum in an application like that so the cylinder bore is always either a cast iron insert (like the Northstar) or a coated bore (like Nikasil) or , in the case of a Reynolds 390 aluminum block with high silicon (a la Vega, Mercedes, Porsche, BMW, etc...) the piston is iron plated so as to prevent aluminum-to-aluminum contact.

Interestingly....a simple Briggs and Stratton engine (there must be millions and millions of them slaving away) has an aluminum bore and an aluminum piston since it is a cost effective way to make a limited use engine with low output yet it seems to run fine with ZDP in the oil and the more ZDP the better.....

I would give those "students" a failing grade, make them dissassemble an engine to find out what is in it and fire the Washington Post for publishing the drivel. They only did it, I'm sure, because it smacked of sensationalism if it were to be true then they could be the ones with the scoop.

"Experts at the American Petroleum Institute told TheCarConnection they were not familiar with the Ontario study."......yea, right. They were probably choking back their laughter which is why they were "not familiar with it.."

thanks for the input bob , i figured this was BS but i thought id let you take a look and lets us know what really goes on...I had a hard time myself thinking where Alum and Alum would contact eachother in a engine ...figured i was missing something ...