Oil film thickness - recommended oil

[Pidziek]

Hello,

I have a question for you.

The man page for the repair of Toyota Motor 4A-FE/ 2C-E (Oryginal factory repair manual toyota corolla) :



There are two marked values.

Do you know any value of the oil film thickness that would be best ?

Does anyone has information about the oil film thickness, eg:

10W40 A3/B4 Ci4/ CH4 or 5W50 5W40 ?

Perhaps somewhere are about optimum lubricant film thickness?

I approach to the subject very thoroughly and I want to investigate the optimum oil film thickness for this engine.

I will be grateful for the professional statements in the topic.

Maybe someone has data on the oil film thickness by. Data cSt. vs temperature vs lubricating layer thickness ?

B.regard
Peter

 

[Jim Allen]

For the most part, that question is answered for you in the owner's manual. They pick the viscosity best for the engine. The only time any radical changes are needed from that basic recommendation is if you step way outside the operating parameters.

Two concepts you need to study (please Google them) are hydrodynamic lubrication and boundary lubrication. Your "oil film" terminology refers more to the latter than the former. You will find a fair bit of info compiled at the homepage for this forum www.bobistheoilguy.com>. Have fun!

 

[Zaedock]

X2 on what Jim said.

Looking at the chart you posted, I can tell you that the tolerances listed for each clearance are pretty typical in automotive ICE's.

I found a couple of good sites when googling "motor oil film thickness". Good luck with your search.

 

[brandini]

What would probably be best to do it to find the oil pressure requirements of the engine, install a gauge, and pick the weight that meets the low end of the range they'll give you under normal operating temperatures.

 

[mechtech2]

There is a new assembly range given , and a wear limit.
There is quite a difference! [This is very normal]

What is best for one is not best for the other.
So is your engine new or well worn?
A 5-30 oil is good for a good engine.