Rubbish advice on BITOG these days...

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Originally Posted By: Shannow
I disagreed that the engine designers, en masse, were intentionally relying on jamming excess oil through the bearings to keep them cool.

In an IC engine, the supply pressure is there to ensure that the worst bearing receives adequate volume of oil..

En masse, maybe not. However there is info out there about using higher supply pressure in high performance applications to increase bearing flow to help keep bearing temperature down so bearings are less susceptible to damage. Our viewpoints differ there, but it's OK to agree to disagree.
 
I can work in that realm...
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The engineers rely on oil pressure within the normal life expectancy of the device. They design flow to be adequate as bearings wear and still be adequate near wear limits. New motors that are tight will exhibit either higher than needed pressure, or will be in by-pass. It's at the other end of the bathtub curve where things get off track ...
 
isn't it key to stay away from that other side of the curve as long as possible? And will running slightly higher viscosity oil from early on help with that, rather than going up after you recognise the first symptoms of low oil oil pressure?
 
As the bearings wear and the clearance increases, the oil flow volume coming out of the PD pump will still remain the same (output volume vs RPM curve) if the pump is not worn and still in good shape. Forced lubrication will still be there, however the oil pressure seen on the gauge will be somewhat lower due to less overall flow resistance of the oiling system from the worn bearings (takes less force to flow the same volume).

The portion of the total flow coming out of the pump that goes to the bearings will increase (for both Qh & Qp) due to more clearance and less flow resistance. That means some of the other components that receive forced oil flow would see a corresponding decrease in flow volume. An extreme example would be if the bearings were so worn that a huge majority of the pump's output was going through the bearings, then the rest of the engine would be lacking of oil flow since a much higher percentage of the total output volume is now going through the worn bearings. Extremely worn bearings can have a negative effect on the whole oiling system.
 
Well, the thread subject is concerning rubbish. Not sure if you're pro-rubbish or anti-rubbish. Planned? ... doubt that.
 
Why not have another endless and useless and condescending debate with ZO to keep you busy - I like to read the first one and then then go directly to page 14 ...
 
OK, since YOU are an proponent of the Bottle Glug Test of 5W oils at -40C, would you like to explain what the tests actually prove when presented as evidence of "something" to a newbie asking a question about starting his car ?

Easy question, eh ?

Or I refer you back to the title of the thread...
 
You are putting your info in and not mine - I actually have run viscosity tests and don't take anything away from their value. But coincidentally the temp in question on the actual post is right where a household freezer operates. Not extreme.

So when a boutique oil that carries rotational test data can't even muster a "glug" at that temp - I'm not trusting the data they publish ...
I have to wonder how "synthesized" it that - or is it still too waxy ?
I'm not going to use it if I get sent back to Russia ...
 
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