Oil change in my 1977 911

[John2244]

Hello,

I’ve done many oil changes in my 912s over the years but about to change the oil for the first time in my 1977 911 S. I have the trombone style oil cooler and would like to know does all the oil from the trombone oil cooler drain back into the oil tank ?? Or do I need to get the oil to operating temperatures so oil drains out of the Trombone oil cooler before I start the oil change ?? I am thinking if the oil does not drain back into the oil tank when cold
there probably isn’t a lot of oil left in the lines to make much of a difference.
I would appreciate your recommendations.

Thank you, John

[smadsen]

I think most DIYers and professionals just ignore the oil in the cooler & lines. Prolly only a quart or two, and you're adding 11 or so clean quarts.

That said, I tried running the car up to temp, quickly lifting the nose of the car and pulling both drain plugs, thinking the gravity and open thermostat would allow the cooler and lines to drain. I think the lines drain, but the suction won't drain the cooler. I believe the refill required a quart more than usual, soooo.

There was at one time, an aftermarket (Elephant, I believe) brass tube replacement that had a Schrader valve incorporated on the tube that allowed you to run the car up to temp and then put 20 psi of air in the line to flush the lines and the cooler. I never heard whether that really worked or not, but it sounded like a good idea. Pretty pricey if I recall.

[911obgyn]

If you havent done an oil change on a 911 just make sure you use a LARGE oil pan under the tank and be aware there will be splash! Dont use the tank type with a tray on top. Its amazing how fast the hot oil comes out and its a lot.

[MichaelSJackson]

^^+1

BIG OPEN OIL PAN.

Ask us how we know.

[John2244]

Thanks for the recommendations. I do have the tank type with the tray on top I was planning to use but will now purchase a big open oil pan. Thanks so much for saving the big mess I probably would’ve created.

Regards, John

[Otter74]

If you'd used that pan you have when you drain the oil you'd have had 3/4 of your oil tank on the garage floor in under a minute.

[rwest]

Picture the case of oil that 12 bottles come in and that is about how much capacity you’ll need.

[John2244]

I have the capacity, I think it’s 16 quarts, but probably would drain to quickly into the tray before it drains from the tray into the tank itself.

[sean m]

Originally Posted by John2244

I have the capacity, I think it’s 16 quarts, but probably would train to quickly into the tray before it drains from the tray into the tank itself.

"the horror, oh, the horror". It comes out fast and furious.
Be prepared.

[John2244]

I changed the oil a couple of days and used a 24 quart pan. Worked perfect. I did run the engine while setting up a few things for the removal process so the oil was only warm when drained. FYI, I was curious so I measured how much oil was removed. I drained 9 1/2 quarts from the oil tank and the engine not counting oil that was in the oil filter.

[gamin]

Post #2 - As far as I know the Elephant Racing oil lines are still available. I have them on the '70.
They work as advertised. Used the schrader valve. Used 80 psi. Elephant recommended using less than 90. Oil line oil went to the oil tank. Won't have any of that dirty oil in the new oil. I like it.

[GH85Carrera]

Just ignore the oil in the cooler lines. I change my oil every 12 months. The 2 quarts left behind is not that much. It don't see it as worth worrying about.