Still having oil Detergents confusion....

While technically true their source is still labeled by the labs who provide the UOA as "Detergents". We then remark how different formulations have different levels of these elements which people then infer as differences in the comparative amount of additive or differences in formulation (ex, SP vs SN). Without this segment of the UOA a lot of what is spoken and worried about on BITOG would vanish.
Since these levels appear to be of no significance maybe they should stop reporting them all together. Just show contamination/wear info.
 
So detergents are more like Scotchgard then a true detergent.
If you cook a lasagna in a ceramic pan, invariably, some of the cheese bakes onto the ceramic and requires scrubbing to remove, just dumping some dawn on it and running some water over it isn't going to take it off, heck, even putting it in the dishwasher won't remove it. This is similar to trying to remove varnish, if you don't have something that can attack and dissolve the deposit (think oven cleaner for example, a strong solvent), it's going to require physical scrubbing to remove. Dawn makes the removal easier, with scrubbing, and helps carry away the material you break off, but it's not going to remove the deposit by itself.

On the other hand, the grease/oils in the bottom of the pan, which aren't adhered, some hot water with some dawn, let it sit, it will rinse off. This is somewhat similar to how sludge/emulsification can be removed by an oil.
 
I keep reading conflicting information on detergents in motor oil. Some sources say they clean, others say they keep deposits from forming on surfaces. Can they do both, or which is it? Does one do a better job then another?

What in motor oil actually cleans up old deposits? Is it the base oils used?
Yes, even after all of the discussions we have had on BITOG. Do a search on "Question of the Day" where in the past we discussed most if not all of these additive components.

"Oxidation inhibitors, detergents, and dispersants make up the general class of additives called stabilizers and deposit control agents. These additives are designed to control deposit formation, either by inhibiting the oxidative breakdown of the lubricant or by suspending the harmful products already formed in the bulk lubricant. Oxidation inhibitors intercept the oxidation mechanism, while dispersants and detergents perform the suspending part.

Detergents neutralize oxidation-derived acids as well as help suspend polar oxidation products in the bulk lubricant.

Dispersancy (as in organic dispersants) pertains to a dispersant’s ability to suspend by-products of combustion, such as soot, and lubricant degradation, such as resin, varnish, lacquer, and carbon deposits..." Lubricant Additives Chemistry and Applications, chapters 4 and 5, by Leslie Resnick, editor.

Some base oils such as esters can also act as detergents by dissolving and suspending carbonaceous
materials. HPL's Engine Cleaner has the chemistry to do all of the above.
 
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When I worked for Toyota we had the V6 sludge motors. I was removing heads to clean and replacing seals. I tried new engine way but Toyota sent a bulletin for us to remove oil pan and pressure wash only. Only if it smoked afterwards could we request a new engine.
 
I keep reading conflicting information on detergents in motor oil. Some sources say they clean, others say they keep deposits from forming on surfaces. Can they do both, or which is it? Does one do a better job then another?

What in motor oil actually cleans up old deposits? Is it the base oils used?
Zddp? Solvents?
 
Detergents are there to prevent deposit formation. They can clean up sludge, but are not sufficient to solubilize varnish films. @OVERKILL has a nice flowchart that helps delineate the difference between sludge and varnish. Significant solubility is generally achieved by incorporation of specially engineered Group V base oils.
Back in 2005 or so when I raced my rx-7 one of the guys kept on and on about using non-detergent oil as detergents would "attack" bearings. It took me forever to get him off that kick. I told him if detergents in oil attacked bearings wouldn't alot more engines be self-destructing than do?
 
People like to obsess over things even if they don't understand the significance.
And people like to make wild claims to try and fit their misconceptions - wild stuff that hasn't been heard for years. Seems to be a growing theme lately.
 
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