jimish

What is a good operating temperature for oil. I have a oil cooler with a fan that comes on at 175* water temp, the oil seems to stay about 30* behind the water. When water is 200*, oil is 165*, when the water is 180*, oil is 150*. I thought oil usually ran hotter than water.

LoneStarFRC

You are correct. It usually does run hotter and in fact the circulating oil actually provides some level of engine cooling along with the radiator in the average vehicle. I have seen figures in the15%-20% range.

IMHO, the oil temps you are indicating are a bit too low. The oil should be around the 200* - 210* range (give or take) if for no other reason than to boil off or at least speed the removal of normal water condensation in the crankcase. Oil temps that are too low can hasten the buildup of sludge and other deposits.

On a hot day, in stop and go type driving I usually see anywhere from 215* - 230* and think nothing of it. Steady highway driving it usually stays around the 205*-210* range.

HTH

sperkins

Also, the oil should reach at least 160* minimum before any spirited driving. This allows for expansion of the aluminum block and internal components so proper tolerances are achieved. I usually wait for 180*.

jimish

Thanks for the feedback. I will change the fans to come on at a 210* water temp. The oil will be circulating through the cooler, but the fan won't be on.

LoneStarFRC

Excellent idea.

The big advantage you have with an oil cooler is that it will prevent (or greatly minimize) the chance of oil OVER heating during any EXTENDED period of spirited/performance driving. They are great for keeping the upper temps from climbing too high, but in your case it was also keeping your temps TOO low.

BTW, you may need to tweak your oil cooler fan temp setting a bit to find the right oil temp range, since there is always a bit of a "lag time" between the fan kicking on and the temp actually coming back down, during which the oil MAY get a bit higher than what you want. You may want to consider having the oil cooler fan kick on at say 200* water temp for a starting point and adjust as needed from there.

HTH

XtremeVette

I been following this and some other threads. My question is this: I know the "sweet spot" for the oil is suppose to 200-210. What if you car has the fans coming on earlier and a 165 T-stat so the oil usually is around 185-195 most of the time as I don't drive the car very much or very long. I usually take it out for like 30 mins or less here and there. BUT, I do spirited driving and occasionally every other week or so get it on the highway and the oil temps there get up to around 200 as the car is fully warmed up and is driven for at least 30 mins on a 20 mile trip. This look like I am safe or should I at least bump my T-stat back up to 180? My coolant temps seem to be really good with my 165Tstat in there. They average 180-195 most of the time and I hardly ever seen them get hotter then 200. (I live in TN)

I guess my question really boils down to: Since I don't drive the car often or far, even if it was stock....the oil temps would still have a hard time staying in the warmed up "sweet spot" of 200-210. Its just unavoidable and the way my car is. I only put in a lower T-stat and had the fans turned on lower to lower the coolant temps a bit. I am not talking a lot here either....Maybe 10 degrees lower then stock.

LoneStarFRC

In your case you may want to consider tweaking your radiator cooling fan temps upward just a tad bit more since you do a lot of short trip driving mostly. You're not far off the mark so I don't know that I would necessarily lose any sleep over it, but I only mention it because a lot of short trip driving without everything coming up to normal temp ranges can cause any moisture in the crankcase oil to not get "boiled" off so-to-speak, and become a problem over the long haul. This also underscores the need to keep your oil changed on a regular basis too.

HTH

XtremeVette

Ok thanks....pretty much what I figured. I read a lot of posts by Evil Twin and I think this is pretty much where he was with it too. I do check my oil often (usually every weekend) and I change it at the correct intervals. I agree with you, seeings I am so close I am not going to lose any sleep over it. I will try to make a habit out of driving the car a little more often and for longer durations to get everything warmed up.

I guess its like saying "when its your time" its your time lol. People smoke, never get cancer and then you have someone who takes care of themselves and gets it. Sorta sounds that way with engines too. You can have one that gets treated like garbage but never ever has a problem and yet then have another that is well taken care of and maintained yet has a catastrophic failure with only 30,000 miles on it.

LoneStarFRC

Sounds like you have a good take on things here.

Besides, like the old saying goes, "If you ain't drivin' it you ain't enjoyin' it".

Me? I have 151K on the car and still enjoying it.