Oil Pressure - Temp Question

[Super_Dave_D]

Help a rookie out. Does my oil temp and pressure, at idle, look OK?

Outside temp - 90 deg
Car driven about 40 minutes
Idle for 5 min.
oil - 20w50

Also - Friday I sat in traffic for about an hour and my temp guage went about the second mark. I was a little worried but after it reached a certain point it stopped but it seems a little high for my comfort.

Is 20W50 the weight I need to be running for Florida high temps?

[Joe Bob]

Pressure should not hit zero at idle and should follow the rpms.

Also....if you look from the passenger side of the steering wheel BACK at the oil temp gauge....most likely you will see tiny numbers. Most of the time the range is in Celsius....I used to have a pic. I'll look around but if you do a search it will probably pop up in an older thread...

The numbers are under the inside bezel.

Temps....

180F good
180-220, normal
220-250, warm
250-280, hot
280-300, real hot
300-350 too freaking hot
350+, get yer check book out.....

[Joe Bob]

Per the "man" Will Ferch....

I've posted on this before..the archives is your friend.
For your 86....
- bottom white block ...60 degC....140 degF
- next up white line, 8 0'clock ...90 degC...194 degF
- next up white line, 10 0'clock...120 degC...248 degF
- bottom of red block ...150 degC...302 degF

If you allow a little "fudge" factor...these can be estimated as:
150-200-250-300 degF ! Don't need no stinkin' numerical gauges

---Wil



And YES I'M BORED.....waiting on the wife and monsters to get ready for the Easter dinner trip down to SmelLA....

[Super_Dave_D]

So is the pressure OK at the RPM's indicated?

[Joe Bob]

yup.....

Hot months and rush hour traffic I would use a single digit weight oil....like straight 30 or 40.....but that's fine.

[bigchillcar]

yup.....

+1 agree with mike, your numbers are just fine.

i run castrol 10w-40 in the arkansas winter and 20w-50 in the hot, humid arkansas summer. the '50' is the weight on the higher end of the temp spectrum and helps to afford a little more protection against the heat. keep using it, imho.
ryan

[Super_Dave_D]

Thanks guys I appreciate the help!!

[diabolos88]

is straight 50weight available?

[bigchillcar]

(from 'how stuff works')
Multi-weight oils (such as 10W-30) are a new invention made possible by adding polymers to oil. The polymers allow the oil to have different weights at different temperatures. The first number indicates the viscosity of the oil at a cold temperature, while the second number indicates the viscosity at operating temperature. This page from the Sci.Electronics.Repair FAQ offers the following very interesting description of how the polymers work:

At cold temperatures, the polymers are coiled up and allow the oil to flow as their low numbers indicate. As the oil warms up, the polymers begin to unwind into long chains that prevent the oil from thinning as much as it normally would. The result is that at 100 degrees C, the oil has thinned only as much as the higher viscosity number indicates. Another way of looking at multi-vis oils is to think of a 20W-50 as a 20 weight oil that will not thin more than a 50 weight would when hot.
ryan

[bigchillcar]

is straight 50weight available?

it's still available. i think some still use it occasionally in motorcycles. don't know of anyone personally who's run it in their car. once your car reaches operating temp, if you're using 20w-50, it's basically operating as a 50-weight oil...the 20 though should provide for less internal resistance at start..particularly if the oil is cool. multi-viscosity oils are designed for climates where there are ranges, or in some cases, extremes, of temperature variance.
ryan

[Joe Bob]

There are those that LIKE multi weights and those that don't...just like the dyno versus synthetic debate.

"I" use straight heavy weights on hot day use, high mileage motors. Noticeable increase in oil pressure across the board....