Bearing fit ... engine oil gravity feed

[rotorwrench]

Multi viscosity engine oil uses polymer plastic micro sized coils that expand when they get hot. The expansion of all of those tiny plastic coils is what increases the viscosity when it gets warmed up. The plastic gets degraded over time in operation and becomes useless as a film build viscosity changer. These oils have a finite life in service and need to be changed regularly. SAE 30 gets thin as it heats up to give a film build that stays about the same but all oil degrades with the combustion products it holds that the filter won't remove so it's also limited in life span. Some oil is better than no oil so use what ever you want within good reason but whether one is better than another is debatable to no end.

High EP gear lube is another debate that I won't even get into. Just because stuff is modern doesn't mean it's better.

 

[Jim Brierley]

In So-Cal I run 20-50 all year, my cars are garaged, so are rarely below 60* at start-up.

 

[Benson]

" End Quote

Yes, for all the bearings we work with.

Take a little 5-30, or other multi oil, an warm some in a little saucepan, and and when you can touch it without burning yourself, put some between your index finger, and thumb, and rub them back and fourth, hard. Then do the same thing with 30-Wt., and see what you think.

I hope I didn't tell you more then I know!

Herm.

As always ... thanks for the info that you post!


No on too much ... a person can never learn too much!

 

[johnneilson]

Herm is technically correct in the clearance to dia size of the bearing posted earlier.


I regularly see mis-conceptions and "old wives tales" when discussing such subjects as clearances.


I tell My Kids all the time, you have to value the information found on the web by the cost. Usually, it is free, do your own homework. And yes, I have several Machinery Handbooks that date back to early 1900's, Herm's formula is spot on.


John