Should I just keep adding oil?

[gjmascoli]

After an engine drop and a lot of upgrades I am pretty certain the engine was bone dry. Note that upgrades included SSIs, so the engine has the requisite oil plumbing that is not stock, as well as Carrera chain tensioners (stay tuned for a post about my worries related to these ).

After filling with 9 quarts (Valvoline VR1 20W-50) and driving a bit to get to temperature, the dip stick was dry. Added another quart and drive, still dry. Added another quart, drove about 25 miles, dipstick is still dry. All oil level checks are at idle, hot engine 180F.

So I am at 11 quarts. Oil pressure seems OK, although I was surprised to see it spike to 130-140 psi when the engine is cold, but it was about 35F today. With the engine warm, pressure hung around 60psi.

Original Owners manual says capacity is 11.57qt. Says oil change is about 10.6qts. Haynes says the capacity is 13.7qts, and I've seen reference in other posts to 13+ qts total capacity.

Sooooo.....keep adding oil until is see something on the dip stick? Engine isn't smoking, but does seem noisy compared to before the engine drop (back to my worry about the tensioner upgrade).

[faverymi]

What 911 is it?

External oil coolers?

Aftermarket oil coolers?

[gjmascoli]

'76 911S 2.7L. No external or aftermarket oil coolers.

[faverymi]

My 2.7 takes 11-12 quarts per change.

No coolers no nothing.

I would be 100% sure that is at fully operating temperature.

Is like 30s here in Bean town

[gjmascoli]

Hmmm, I'll admit that I had been driving about 25 miles and oil temp was a steady 180F before I stopped at the grocery store which allowed engine to cool a bit. Then I drove home 2 miles and let the engine idle, but I probably wasn't all the way back to 180F.

What is it that is happening mechanically in the engine that makes the temp so critical when checking the oil?

[Dodge Man]

Put in 9 and then add oil until it hits the stick after warming up. Just be sure to put in the 9 before starting up. Motor conversion cars are pretty picky about filling to the top.

[77Targa0912]

My 77 911S with the factory oil cooler takes 12.5 quarts.

[fanaudical]

As I understand it, there are several things going on that make temperature important:

- Oil is expanding somewhat with warmer temperatures (volume of oil increases with temperature)

- There is some aeration that occurs in the 911 oiling system (Some air is entrapped in the oil in the tank upon its return. Not a major contributor to the volume change, but it does occur.)

- As the functional viscosity of the oil goes down with temperature, so does the fraction of oil in the sump versus the tank. The oil sump return pump does a better job at scavenging the oil from the sump and getting it back to the tank when warm, therefore also affecting the volume in the tank and reported on the dipstick.

[Reiver]

If it's not registering on the dipstick add another 1/2 qt. at a time until it does. Once warm or course.
As long as you have oil pressure you are still ok, doing no harm....you just need to get the level to register is all.

[gjmascoli]

Phew! OK all, thanks for the input!

[wwest]

Properly filled, COLD oil will not show on the dipstick, only at operating temperature, and only check with the engine running.

[Bill Douglas]

My thoughts are there was some quantities of oil in the oil lines removed and replaced. And this has made some difference.