Engine Oil Level

[BobBrumby]

After doing a few seals and stuff I filled up the oil to just a little below the full hole on the dipstick. About a month later, today, I checked my oil out of interest once the car had warmed up to find it a bit over the full mark. Is it normal for oil to expand when its heated? And is the full mark for cold oil?

[Ross]

The mark is for cold level, and like everythig else, oil does expand somewhat on heating. For a noticable change however, you may be looking at water and petrol dissolved in the oil, which is quite normal. does the car get a lot of stop start driving?

[BobBrumby]

The mark is for cold level, and like everythig else, oil does expand somewhat on heating. For a noticable change however, you may be looking at water and petrol dissolved in the oil, which is quite normal. does the car get a lot of stop start driving?

 

yeh in brisbane, no doubt.

now i have fixed all the leaks i might just run it a bit lower so the oil level is never over bottom of the crank gear for the cam.

[All_talk]

Not sure about Subies but most cars I've dealt with the oil is to be checked hot (engine off). And yes oil can expand significantly from cold to hot, I havent check it on my Subes but I've seen differances of 1/4 or more on the stick for some cars from hot to cold.

 

Gary

[KStretch55]

Not only does the oil expand, but it also gets a certain amount of entrained air mixed into it. The tiny air bubbles will float out, but it will take several minutes.

[BobBrumby]

The verdict, running with over full mark while the oil is hot, does this do damage?

[Ross]

Your oil would have to be very overfilled to cause damage. Just a little won't do any major harm.