Oil change rant
#1
Oil change rant
We have 2 Porsches. A 997 and a Macan. Every time I change the oil I put in the recommended amount and every time the computer may or may not read full. Put in 7.9 quarts on the 997, like always, and now reading at minimum level. Last time did the same and read full.
Just venting. The one advantage of the 996 was a dipstick and cold read in the morning.
Just venting. The one advantage of the 996 was a dipstick and cold read in the morning.
#2
Rennlist Member
We have 2 Porsches. A 997 and a Macan. Every time I change the oil I put in the recommended amount and every time the computer may or may not read full. Put in 7.9 quarts on the 997, like always, and now reading at minimum level. Last time did the same and read full.
Just venting. The one advantage of the 996 was a dipstick and cold read in the morning.
Just venting. The one advantage of the 996 was a dipstick and cold read in the morning.
#4
RL Community Team
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We have 2 Porsches. A 997 and a Macan. Every time I change the oil I put in the recommended amount and every time the computer may or may not read full. Put in 7.9 quarts on the 997, like always, and now reading at minimum level. Last time did the same and read full.
Just venting. The one advantage of the 996 was a dipstick and cold read in the morning.
Just venting. The one advantage of the 996 was a dipstick and cold read in the morning.
Said again, I get variable reads immediately after an oil change. I asked the tech about this also.... he said after a change, start the car and let it idle... go get some coffee.... 5 to 10 minutes of idling... then measure. Sounds pretty stupid to me but that is what he said.
Peace
Bruce in Philly
#5
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Once filled, let idle to help get oil up to somewhere decent temp and worked throughout the engine, and then check level after sitting turned off for a bit.
#7
Advanced
2010 C2S here.
Just did an oil change recently, and after letting car sit/drain for 1.5 hours with rear tires driven up on 2x4's, It took 8.5QT for oil level gauge to read full.
Regards,
wm
Just did an oil change recently, and after letting car sit/drain for 1.5 hours with rear tires driven up on 2x4's, It took 8.5QT for oil level gauge to read full.
Regards,
wm
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#10
RL Community Team
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The oil pump in our cars is pumping a mass amount of oil fast. In the vid below, it circulates the full amount of oil "4 times a minute at normal speed". While our Porsche engines may not be pumping at that rate, more or less is possible, it still illistrates that a big amount of oil is circulating. I have trouble believing that it takes 5 to 10 minutes to have oil "worked throughout the engine". By that time, something would have blowed up real good. I suspect a few seconds of idling gets the oil everywhere it needs to go. The vid also said another interesting fact: the oil pump will fill a bathtub in three minutes.
Peace
Bruce in Philly
The first part of the vid is stupid so go right to 4:20 where the good stuff starts. Or go directly to 9:44 for a really cool demo where they hook a hose directly to the outflowing part of the pump and let fly with it..... again, 5 minutes to have the oil "stabilize" to me sounds stupid.
Last edited by Bruce In Philly; 01-23-2018 at 08:44 PM.
#11
Nordschleife Master
...
Said again, I get variable reads immediately after an oil change. I asked the tech about this also.... he said after a change, start the car and let it idle... go get some coffee.... 5 to 10 minutes of idling... then measure. Sounds pretty stupid to me but that is what he said.
Peace
Bruce in Philly
Said again, I get variable reads immediately after an oil change. I asked the tech about this also.... he said after a change, start the car and let it idle... go get some coffee.... 5 to 10 minutes of idling... then measure. Sounds pretty stupid to me but that is what he said.
Peace
Bruce in Philly
#12
RL Community Team
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Can one of you engineers tell us how much motor oil's volume changes with temperature? Then we can swag how much the meter on our dash board would change between cold and hot oil.
Peace
Bruce in Philly
Peace
Bruce in Philly
#13
Thermal expansion of motor oil example on this page:
https://www.engineeringtoolbox.com/v...ion-d_315.html
Seems to be around 1% for temp increase from 20C to 40C
Based on my calculations, from 70F to 225F, 8 Liters expands to 8.4836, using the 0.00039 factor in the expansion table.
https://www.engineeringtoolbox.com/v...ion-d_315.html
Seems to be around 1% for temp increase from 20C to 40C
Based on my calculations, from 70F to 225F, 8 Liters expands to 8.4836, using the 0.00039 factor in the expansion table.
#14
Nordschleife Master
From my experience with air-cooled engines holding 12qt of oil, I see volume expansion of at least 1/qt (on the dipstick) between 68F and 210F.
#15
Well I added another quart. Drove my daughter around until up to temp. Checked and went to full. So 9 quarts this oil change. 8 last time. So my working theory is every third oil change takes an extra quart.