Grandma's CRX - what oil to use!

foxdonut, Dec 26, 11:34am
Nanna's little red over-locker needs and oil change - Early 90's CRX Del Sol - D15b 1500 single cammer vtec motor. Mostly used for short stop and go shopping trips. 180k on the dial.

20-50 or 15-40!

Anyone know of oil and filter combo deals that are on at the moment!

jono2912, Dec 26, 11:45am
5w-30, or 10w-40

lugee, Dec 26, 2:29pm
10w40 at the thickest, 5w30 is you don't mind a couple of extra bucks.

the-lada-dude, Dec 26, 7:54pm
whale oil, but it is getting hard to come by, although the japs have some stocks.
if you tell them its for scientific purposes you might get a barrel or two.

jasongroves, Dec 26, 11:32pm
15w-40 or 10w40, SG rated (hard to find an oil that isn't rated above that anyway:)

mrcat1, Dec 27, 12:26am
You can get SI and SM rated oils but yes not much point as SG is most likely a better rating than when the car was new.

mrcat1, Dec 28, 6:46am
I have just been in Kmart and saw they had a Shell Helix synthetic oil, either a 4 or 5 liter SM spec oil for 39.95. That would do, just can't remember grade sorry.

jasongroves, Dec 28, 7:18am
Yeah, I meant SG as a minimum;)
.and that the majority of oils available would meet or exceed that rating.

lugee, Dec 29, 5:23am
I've found that using oil any thicker than 10w40 makes revving up once the engines started harder, and it will run sluggishly until the oil thins.

mrcat1, Dec 29, 6:41am
Ha Ha, the 10 in the grade is the cold rating, the hot rating is the 40 so as it gets hotter it gets thicker. Please explain this thoery some more.

utwo, Dec 29, 11:14am
Oil thins when heated and thickens when cooled.
http://www.castrol.com/castrol/genericarticle.do!categoryId=8264018&contentId=7007302

A 10W/40 multi-grade oil, for example, is designed to have the viscosity of a 10 grade oil when cold and a 40 grade oil when hot. A 40 grade oil when hot is thinner than a 10 grade oil when cold, but is thicker than a straight 10 grade oil would be when hot. In other words, a multi-grade oil thins out much less than a single-grade oil as the temperature rises.

mrcat1, Dec 29, 11:35am
What a load of double dutch, as the oil heats it thickens to the 40 weight grade then as it cools it thins back to a 10 weight grade. Read properly the article in the link, it even tells you exactly the same as i have said, and explains that the thickening additives become dormant when cold.

utwo, Dec 29, 10:18pm
The viscosity of a multi-grade oil still varies logarithmically with temperature, but the slope representing the change is lessened. In other words, the "thickening" additive slows down the rate of thinning as the oil warms up.

Click this link for some examples. Compare the viscosity of these oils at 100 degrees with the viscosity at 40 degrees. All of the oils on this list are 5W/40 with one exception.
http://img.photobucket.com/albums/v80/TheGSRGuy/oil/oil_chart.jpg

muzzaandmich, Dec 29, 10:35pm
Why not use cooking oil by the time it's done 200k it will be cooked

moosie_21, Dec 29, 11:15pm
lol, if you knew ANY basic physics you would know liquids thin as they heat up and expand as they cool down due to molecular activity. Need to go back to high school do we!

mrcat1, Dec 29, 11:54pm
MMMMMM so a oil with a viscosity of 5/40 can reach a viscosity of 100 at 40degrees C, interesting.

mrcat1, Dec 29, 11:55pm
Maybe you need to see what he has posted as well, or you need to get out more.

mrcat1, Dec 30, 12:11am
So they must have to put oil in a fridge in the out back of aussie before they can change the oil in a vehicle, if it gets up to 40 degrees it will become the viscosity off 100 and you won't pour it very quickly out of the container. Interesting concept.

utwo, Dec 30, 12:32am
It helps if you know what the numbers mean. Viscosity @ 40 degrees C is the kinematic viscosity of the fluid at 40 degrees Celsius. The kinematic viscosity is essentially the amount of time, in centistokes, that it takes for a specified volume of the lubricant to flow through a fixed diameter orifice at a given temperature.

The following link provides a good explanation of what the SAE grades, e.g. 5W-40 actually mean in terms of viscosity.
www.upmpg.com/tech_articles/motoroil_viscosity/

mrcat1, Dec 30, 1:04am
That may be the case but the other chart you posted showed the viscosity and 40 degrees C and had one oil @100.4, thats quite a interesting idea. I actually know how the oil viscosity works in oils. i want you to explain why they are showing a Viscosity of 100 @ 40 degrees.

mrcat1, Dec 30, 1:07am
OK . . .What does a 5W-30 do that an SAE 30 won't!
When you see a W on a viscosity rating it means that this oil viscosity has been tested at a Colder temperature. The numbers without the W are all tested at 210° F or 100° C which is considered an approximation of engine operating temperature. In other words, a SAE 30 motor oil is the same viscosity as a 10w-30 or 5W-30 at 210° (100° C). The difference is when the viscosity is tested at a much colder temperature. For example, a 5W-30 motor oil performs like a SAE 5 motor oil would perform at the cold temperature specified, but still has the SAE 30 viscosity at 210° F (100° C) which is engine operating temperature. This allows the engine to get quick oil flow when it is started cold verses dry running until lubricant either warms up sufficiently or is finally forced through the engine oil system. The advantages of a low W viscosity number is obvious. The quicker the oil flows cold, the less dry running. Less dry running means much less engine wear.