Strange oil level issue
#16
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Another possibility is the oil temp. Are you consistently performing a drain with cold engine, warm engine or hot engine. It will make a difference in the volume of oil that drains. My racecar (3.4 l air cooled six) has a capacity of 16 quarts. I can only get 9 qts to drain and filling with nine qts will not show on the dip stick until the engine comes up to operating temp. Lots of volume change due to oil temp.
#17
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same method for years. lift car level. drain oil. put 8qt back in. all done. never had any issues.
I've had my car for over 9 years now and have always done my own oil changes. I overfilled once. It was the first oil change and my method was jacking up only the rear end of the car. I put the specified quantity of oil in and it was overfilled. Ever since that time I raise the car to level (I have a Quick Jack) and I've never had another problem with overfill. I attributed my over fill with lack of full drain with just the back of the car in the air. What is your method of oil drain?
#18
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don't think the situation I am in has anything to do with the way I drained and filled the oil and/or how much I did. Have been doing it the same way for years. Never once was there any difference/change in oil level as displayed by the gauge. Even after the last oil I have driven the car a couple of hundreds of miles without any issues until last week when the oil level changed by two units (probably around 1/2 qt. ) but went down one unit after I stopped to get gas. I haven't had the time to look more into it, the weather isn't to nice. It's actually snowing right now. The good news is that it's def. not coolant in the oil.
Another possibility is the oil temp. Are you consistently performing a drain with cold engine, warm engine or hot engine. It will make a difference in the volume of oil that drains. My racecar (3.4 l air cooled six) has a capacity of 16 quarts. I can only get 9 qts to drain and filling with nine qts will not show on the dip stick until the engine comes up to operating temp. Lots of volume change due to oil temp.
#20
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If you have a diagnostic tool like iCarsoft you may read out the oil level in mm . For the MA 1.03/ 1.04 engine of the 991.1 the reading in mm is about equivalent to the amount in liters in the sump, multiplied by 10.
A "normal" indication ( as per factory recommendation for tracked cars), with top of scale minus 2 bars would be around 78 mm. The diagnostic tool will allow you to much more precisely check the indicated oil level than you can do with the dashboard indicator with its coarse 0,4 liter steps and its hysteresis of indication ( "quantization error").
Though the actual oil level will vary with temperature and time between last operation of the engine, the indication in the instrument cluster tries to compensate these influences with a software model.
I always change the motor oil with the motor "cold" , after it has been sitting at least over night. This allows the oil to flow back into the sump as much as possible. I then drain the oil until only a few drops per minute still run out, which may take about an hour. This usually results in about 8 liters ( 8 1/2 quarts ) to be refilled to achieve the previous oil level. If you fill until indication "minus 1 bar" it may require even more.
Clearly, If the oil is changed under workshop circumstances, then the oil should be at operating temperature (how realistic ?), to achieve fast draining after the car was moved onto the lift. The specified amount 7.5 ltrs/7.9 quarts of oil refer to this situation, with 20 minutes of draining. About 2 ltrs of used oil still will remain in the motor.
A "normal" indication ( as per factory recommendation for tracked cars), with top of scale minus 2 bars would be around 78 mm. The diagnostic tool will allow you to much more precisely check the indicated oil level than you can do with the dashboard indicator with its coarse 0,4 liter steps and its hysteresis of indication ( "quantization error").
Though the actual oil level will vary with temperature and time between last operation of the engine, the indication in the instrument cluster tries to compensate these influences with a software model.
I always change the motor oil with the motor "cold" , after it has been sitting at least over night. This allows the oil to flow back into the sump as much as possible. I then drain the oil until only a few drops per minute still run out, which may take about an hour. This usually results in about 8 liters ( 8 1/2 quarts ) to be refilled to achieve the previous oil level. If you fill until indication "minus 1 bar" it may require even more.
Clearly, If the oil is changed under workshop circumstances, then the oil should be at operating temperature (how realistic ?), to achieve fast draining after the car was moved onto the lift. The specified amount 7.5 ltrs/7.9 quarts of oil refer to this situation, with 20 minutes of draining. About 2 ltrs of used oil still will remain in the motor.
Last edited by Autobahnschreck; 01-24-2024 at 10:14 AM.
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tomekz (01-24-2024)
#21
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thanks for the extra info. I have access to a decent scan tool and well as PIWIS III. Will have to check what those show the oil level to be. Just thought that both the scan tool and the dashboard gauge get that information from the same sensor.
If you have a diagnostic tool like iCarsoft you may read out the oil level in mm . For the MA 1.03/ 1.04 engine of the 991.1 the reading in mm is about equivalent to the amount in liters in the sump, multiplied by 10.
A "normal" indication ( as per factory recommendation for tracked cars), with top of scale minus 2 bars would be around 78 mm. The diagnostic tool will allow you to much more precisely check the indicated oil level than you can do with the dashboard indicator with its coarse 0,4 liter steps and its hysteresis of indication ( "quantization error").
Though the actual oil level will vary with temperature and time between last operation of the engine, the indication in the instrument cluster tries to compensate these influences with a software model.
I always change the motor oil with the motor "cold" , after it has been sitting at least over night. This allows the oil to flow back into the sump as much as possible. I then drain the oil until only a few drops per minute still run out, which may take about an hour. This usually results in about 8 liters ( 8 1/2 quarts ) to be refilled to achieve the previous oil level. If you fill until indication "minus 1 bar" it may require even more.
Clearly, If the oil is changed under workshop circumstances, then the oil should be at operating temperature (how realistic ?), to achieve fast draining after the car was moved onto the lift. The specified amount 7.5 ltrs/7.9 quarts of oil refer to this situation, with 20 minutes of draining. About 2 ltrs of used oil still will remain in the motor.
A "normal" indication ( as per factory recommendation for tracked cars), with top of scale minus 2 bars would be around 78 mm. The diagnostic tool will allow you to much more precisely check the indicated oil level than you can do with the dashboard indicator with its coarse 0,4 liter steps and its hysteresis of indication ( "quantization error").
Though the actual oil level will vary with temperature and time between last operation of the engine, the indication in the instrument cluster tries to compensate these influences with a software model.
I always change the motor oil with the motor "cold" , after it has been sitting at least over night. This allows the oil to flow back into the sump as much as possible. I then drain the oil until only a few drops per minute still run out, which may take about an hour. This usually results in about 8 liters ( 8 1/2 quarts ) to be refilled to achieve the previous oil level. If you fill until indication "minus 1 bar" it may require even more.
Clearly, If the oil is changed under workshop circumstances, then the oil should be at operating temperature (how realistic ?), to achieve fast draining after the car was moved onto the lift. The specified amount 7.5 ltrs/7.9 quarts of oil refer to this situation, with 20 minutes of draining. About 2 ltrs of used oil still will remain in the motor.
#22
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Measure the oil with a scan tools today. The dashboard gauge showed the level to be at the top horizontal line (so the maximum good level), however the scan tool showed 65.250 mm..
If you have a diagnostic tool like iCarsoft you may read out the oil level in mm . For the MA 1.03/ 1.04 engine of the 991.1 the reading in mm is about equivalent to the amount in liters in the sump, multiplied by 10.
A "normal" indication ( as per factory recommendation for tracked cars), with top of scale minus 2 bars would be around 78 mm. The diagnostic tool will allow you to much more precisely check the indicated oil level than you can do with the dashboard indicator with its coarse 0,4 liter steps and its hysteresis of indication ( "quantization error").
Though the actual oil level will vary with temperature and time between last operation of the engine, the indication in the instrument cluster tries to compensate these influences with a software model.
I always change the motor oil with the motor "cold" , after it has been sitting at least over night. This allows the oil to flow back into the sump as much as possible. I then drain the oil until only a few drops per minute still run out, which may take about an hour. This usually results in about 8 liters ( 8 1/2 quarts ) to be refilled to achieve the previous oil level. If you fill until indication "minus 1 bar" it may require even more.
Clearly, If the oil is changed under workshop circumstances, then the oil should be at operating temperature (how realistic ?), to achieve fast draining after the car was moved onto the lift. The specified amount 7.5 ltrs/7.9 quarts of oil refer to this situation, with 20 minutes of draining. About 2 ltrs of used oil still will remain in the motor.
A "normal" indication ( as per factory recommendation for tracked cars), with top of scale minus 2 bars would be around 78 mm. The diagnostic tool will allow you to much more precisely check the indicated oil level than you can do with the dashboard indicator with its coarse 0,4 liter steps and its hysteresis of indication ( "quantization error").
Though the actual oil level will vary with temperature and time between last operation of the engine, the indication in the instrument cluster tries to compensate these influences with a software model.
I always change the motor oil with the motor "cold" , after it has been sitting at least over night. This allows the oil to flow back into the sump as much as possible. I then drain the oil until only a few drops per minute still run out, which may take about an hour. This usually results in about 8 liters ( 8 1/2 quarts ) to be refilled to achieve the previous oil level. If you fill until indication "minus 1 bar" it may require even more.
Clearly, If the oil is changed under workshop circumstances, then the oil should be at operating temperature (how realistic ?), to achieve fast draining after the car was moved onto the lift. The specified amount 7.5 ltrs/7.9 quarts of oil refer to this situation, with 20 minutes of draining. About 2 ltrs of used oil still will remain in the motor.