Oil draining for dry sump motor

[ron in sc]

I have always changed oil when hot but in this case I wonder if it's necessary or even advisable.

Would it be better to change oil hot or cold based on the facts outlined below. It would be easier for me to change it cold since it's already on lift.

Car has been on lift for 2 week waiting on a part and will be on lift at least another week.

The facts:
1-air cooled motor with dry sump
2-oil tank holds about 8 liter
3-engine holds less than 2 liters as there is a certain amount of oil in hoses and oil cooler in front of car.
4-car has two oil filters a large filter on thermostat housing at oil tank and a small oil filter on the engine.
5-oil is changed yearly regardless of miles, less than 250 miles put on car in last year
6-I will be using a new oil Motul 300V 15W50; previously using Mobil 1 15W50.
7-removed valve cover gasket to examine part of valvetrain and everything I observed appear clean and new, not even any brown staining. Car has about 15k miles on it.

 

[SteveSRT8]

Ron, sounds just like one of my old 911's!

I always changed them hot because the manual said to. But if the reservoir is all you can empty then there is no sense in having it hot to me if you can patiently wait for all that 50w to drain out.

I never wanted my cars to have to fill all that cooler and line with oil when first started...

 

[ron in sc]

Originally Posted By: SteveSRT8
Ron, sounds just like one of my old 911's!

I always changed them hot because the manual said to. But if the reservoir is all you can empty then there is no sense in having it hot to me if you can patiently wait for all that 50w to drain out.

I never wanted my cars to have to fill all that cooler and line with oil when first started...


Steve, It's a 1997 993 C2S. After oil change you can remove fuel pump relay so car will not start and let pump fill hoses and lines to a certain extent.

With all those filters wouldn't any oil that had contaminates in it be in the tank which is easy to drain?

 

[jaj]

Google "Toyota LFA Oil Change" - there's a video of how it's done. If you follow their approach you'll get a thorough change.

They drain the system, refill it and run it back to warm then drain and refill again. That uses about 28 quarts of Mobil 1 5w-50.

 

[ron in sc]

Originally Posted By: jaj
Google "Toyota LFA Oil Change" - there's a video of how it's done. If you follow their approach you'll get a thorough change.

They drain the system, refill it and run it back to warm then drain and refill again. That uses about 28 quarts of Mobil 1 5w-50.


That will not work. I have dual distributor out and sent off to have belt changed and unit inspected. So I can not start the car; that's why it is just sitting on the lift.

 

[oliver88]

I change mine cold quite often…In the race cars we hold 13ish quarts with oil lines and dual coolers….If you are changing it annually at low miles the oil that remains is probably just as good as the oil you are refilling it with. I would not lose a minutes sleep over it. On a street driven 911 you could easily go 2+ years without having to do an oil change assuming you aren't putting more than 10-12,000 miles on that fill.

 

[SteveSRT8]

Originally Posted By: ron in sc
Originally Posted By: SteveSRT8
Ron, sounds just like one of my old 911's!

I always changed them hot because the manual said to. But if the reservoir is all you can empty then there is no sense in having it hot to me if you can patiently wait for all that 50w to drain out.

I never wanted my cars to have to fill all that cooler and line with oil when first started...


Steve, It's a 1997 993 C2S. After oil change you can remove fuel pump relay so car will not start and let pump fill hoses and lines to a certain extent.

With all those filters wouldn't any oil that had contaminates in it be in the tank which is easy to drain?


all the oil will be nearly identical as it has all been through those filters over and over.

Try to avoid a dry crank, it can be harder on valvetrain components than a dry start!

I would either just leave the slight amt of old oil or figure out a way to prefill everything, filters AND lines and coolers, prior to starting.

But I'm an oil nut...