Rather long but interesting reading

http://members.rennlist.com/oil/Motor%20Oil%20101.htm

I read this article a couple weeks ago. IIRC the author advocates running thinner grade oil until you meet the criteria of 10 psi (what's that, about .7 bar?) oil pressure per 1000 rpm.

Initially I balked, but further study reveals that my pickup getting 44 psi at 2000 rpm actually meets the 10 psi/1000 criteria because the criteria is a minimum and if I run my truck up to 4000 rpm (pretty much the max it is meant to go) I am still getting about 44 psi.

So apparently it is OK to have higher pressure midrange so long as it does not drop below the min 10psi / 1000 rpm anywhere.

In fact, if it always ran exactly 10/1000 up the rpm scale, something would be wrong. Oil pressure should be a upward arching curve, not a straight line.

On start up I assume you hit the pressure relief valve at 44psi, and if so probably would even with a 0W .

With a big capacity engine rather than high rev I would have concerns about dropping viscosity to a 0W20 unless increasing HTHS.

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On start up I assume you hit the pressure relief valve at 44psi, and if so probably would even with a 0W .

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Cold runs about 54 psi at speed. I think the spring resistance must drop when it gets hot. With 5w30 I was getting 35 psi hot. Probably could get away with a 10w30/10w40 mix.

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With a big capacity engine rather than high rev I would have concerns about dropping viscosity to a 0W20 unless increasing HTHS.

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Agree. A big capacity engine running 5w20 should have something like Redline with its high HTHS. A small, high winding V engine probably fine with semi-synthetic 5w20.

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A big capacity engine running 5w20 should have something like Redline with its high HTHS.

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Aha. What is a "high HTHS" for a 5W-20 oil?

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Originally posted by Callisa:

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A big capacity engine running 5w20 should have something like Redline with its high HTHS.

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Aha. What is a "high HTHS" for a 5W-20 oil?

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Redline 5w20 has a listed HTHS of 3.3 cP @ 150C ASTM D4741. That is "high" compared to typical of-the-shelf U.S. 5w20s. In fact, it is comparable to a typical 10w30.

D-4683 is what I see almost all other oil makers use the arrive at an HT/HS for an oil .

I wonder what the difference is in the parameters of these two tests and if one will show a higher value than the other ?

Callisa

With a high HTHS you may be able use a lower viscosiity oil and add some bhp.

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With a high HTHS you may be able use a lower viscosiity oil and add some bhp.

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Yes. And with HTHS of 2,9 you may gain some fuel economy in addition to that.

Callisa,

I take it that you prefer low weight oil, so whats your view on this and its application for engine types (High rev / big capacity)

On page 19 this Shell Global test refers to a SAE paper but also gives other pertinate info on ring modeling , vi and more to include a 5w-20 oil giving higher top ring oil film thickness than a 15w-40 they tested along with viscosity affecting ring movement

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I take it that you prefer low weight oil, so whats your view on this and its application for engine types (High rev / big capacity)

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Well, I have seen some very good 0W-30 oils in terms of wear performance. I could not find any disadvantages compared to 5W-40 oils.
I saw some strange results with a 0W-20 oil (fully ester based) like high oil consumption, increased piston ring wear. Conclusion: Oil and engine have to "fit" to each other, not every engine should be lubed with such an oil.

Ester based oils do not appear to perform well with road engines and maybe this is why M1 has moved away from esters.

Perhaps an HTHS of 2.6 is all thats needed and the thinner oils actually performs better at start up and aids cooling and reduces heat and maintains therefore maintains viscosity at operating temperature, compared to a 5W40 which may thin.

Any comments on fuel as LPG appears to produce low wear.

Has anyone ever compiled a list of automotive/industrial engine oils that contain esters?

A list of oils that contain ester would be interesting. Also would be nice to have the percentage. Could that be found in the MSDS's?

BTW, I understand Valvoline Maxlife initially had about 15% ester, but that after a couple years it was reformulated to instead have about 15% PAO. Would be very interesting to know the reason for the change, but probably had more to do with cost, the PAO being cheaper than ester.

Also, I have heard that a lot of the motor oil additive packages include some ester for solubility, so maybe there is ester in a lot more of the oils than we think, but probably a small percentage I would guess.

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Any comments on fuel as LPG appears to produce low wear.

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Well, oil is deteoriated from blowby. LPG is a very clean fuel. I have seen results with 30.000 km OCI which looked like 3.000 km.

Maybe we should open a new thread which is wear related. What is best case / worst case concerning wear? I have seen some "believes" that cold start is worst case for wear. This is only partly true.
And LPG is not better than gasoline in terms of wear in my opinion. It's just that LPG drivers are most of the time long distance drivers, which is best case in terms of wear.

What information especially from these "you all" reliable sources could be given about Esters?

Esters pros:
Sticks to metal
Good for turbo engine use
...etc...etc...

Esters cons:
Makes seals swell [just guessing]
...etc...etc...


I look around to find out what PAO is and always see PAO but not definition. so much info to plow through using search engine. I must also do work here today, boss giving me "the eye". HAHA

I found something on "Kung PAO chicken" recipe.

This message has been edited. Last edited by: Dynamo^Joe,

Dynamo Joe
Ester info

http://www.silkoleneoil.com/techtip8.htm

I posted a bit more detail from John Rowland on an earlier thread
Esyters General
http://www.hatcocorporation.com/pages/about_esters.html

Redline site has a short presentation.

Motul site also has info.

The advantage of esters appears to be film strength and ability to handle heat (jet engines). For an ICE they are really over the top unless racing or using car for track days.

There does not appear to be any evidence that they prevent wear better than a non ester based oil, even on start up, despite claims by Castrol Magnatec/Start Up.

Castor Oil has been used in racing for many years but gums up engine.

Silkolene is appox 20% diester - Motul 20% diester plus blend of ester and PAO and Redline may have highest ester content. Off the shelf Redline could be used in an F1 car and Motul 5W40 used in WRC.

Callisa
The LPG UOA I've seen is with Silkolene and LPG in UK, so perhaps not just high mileage.

A what cause most wear thread would be interesting.

Most oils have some ester as part of additive package but Molakule has stated 10-30% is required for the Silkolene effect and Magnatec may only contain 5%, so maybe just good advertising.

Other oils that may contain that quantity of ester are probably specialist race oils and may include Royal Purple. Another may be Synlube! and M1 may or may not contain ester - lable states uses 3 Synthetics.

I am thinking for the average automobile or light truck, a little ester may be beneficial in helping to clean deposits from the engine internals.

A little ester may go a long way in cleaning department.

As Auto Rx may be best cleaning ester, what is dose rate.

Another idea for selecting oil thickness. At the tail end of an oil change interval I drained off 40 oz from a 4.5 quart system on my wife's Aerostar and installed 40 oz of 15w50. This vehicle always had 30 weight. I had been topping with the 15w50 and they some Synpower Oil Treatment. It ran fine on straight 30 weight (10w30) at 10.9 cSt 100c viscosity, fine all the way up to about 13 cSt (a very light 10w40), but currently it is up to 14.3 cSt and it feels like the parking brake is left on lightly when I drive it. Perhaps a sign the oil is too thick? Even the engine sounds different, a little lower toned. Will be going back to about a 12 - 13 cSt (about a 10w30/40) .

Here, calculate you resultant viscosity from mixing at this site: Viscosity Blending Calculator