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My car was slightly overfilled from the factory, about 1/8" over the full mark on the stick. I was not seeing any sign of trouble so I let it go until the first oil change. I wanted to do the first change myself to become more familiar with the car. (Z-51)
I had read the posts about the oil fill level so I planned on reducing the amount. When I slid under the car and started looking around I noticed a few drips under the air box. The car's oil level never dropped on the stick, there was no darkening of the exhaust tips or anything else noticeable. There was never any oil on the garage floor.
When I refilled I used a little less than 9.5 quarts to bring the oil level just between the hash marks on the stick. So far, so good. I keep an eye on the level and watch for drips.
Speaking of which, that raises a question I've wondered about.
With the reservoir system, what difference does it really make if the oil is a little low? It's not like it's a matter of the oil pump not being able to keep its intake submerged regardless of angle and/or g-forces as you'd have in a wet sump motor
We could probably run 2 quarts low. The wet sump engine takes only 7 quarts. That's all that is needed unless you're tracking or autocrossing.
Are we talking the air intake where the filter is or the actual intake mounted on top of the engine?
How do you check for this problem?
The dry sump issue burps air through a line that goes from the tank to just after the filter. Assume if excess oil it runs to the filter. Keeping the oil 1/2 quart appears to prevent the problem. The PCV system goes in after the throttle body and that is where excess oil mist can bake on the back of intake valve head and on the stem. I added both a catch can and clean oil separator.
If you have a Z51 get a Catch Can for the PCV system but what causes oil in the air intake prior to the MAS is the burping of the oil reservoir tank. For that you need a “Clean Oil Separator.” See my above post. This is a picture PDF of my install of both for more info than you may want-look at the pics: http://netwelding.com/Catch_Can.pdf
I would also keep the oil ½ quart low, ~½ way in the hatched area.
Catch Can & Clean Oil Separator
I had looked at some of the install videos for the catch can showing it on the left side of the engine. I had wondered if a second device would be needed on the right side involving the vent tubes on the dry sump tank since that appears to have been the source of the burp spillage and oil on the MAS. I read your file about it all and will get the separator and the catch can. Thank you for going thru the effort to write it. I looked at several of your others and plan to take advantage of them as well.
The dry sump issue burps air through a line that goes from the tank to just after the filter. Assume if excess oil it runs to the filter. Keeping the oil 1/2 quart appears to prevent the problem. The PCV system goes in after the throttle body and that is where excess oil mist can bake on the back of intake valve head and on the stem. I added both a catch can and clean oil separator.
Thanks.
My next question is, why doesn't the C6 ZO6/Grand Sport have this problem? Both use dry sump systems. Thanks.
-JP
If you have a Z51 get a Catch Can for the PCV system but what causes oil in the air intake prior to the MAS is the burping of the oil reservoir tank. For that you need a “Clean Oil Separator.” See my above post. This is a picture PDF of my install of both for more info than you may want-look at the pics: http://netwelding.com/Catch_Can.pdf
I would also keep the oil ½ quart low, ~½ way in the hatched area.
Are there any issues with dealers and warranty claims if you make these adjustments?
Thanks.
My next question is, why doesn't the C6 ZO6/Grand Sport have this problem? Both use dry sump systems. Thanks.
-JP
I don’t know but this info from a 2007 Owner’s Manual provides an explanation of why you must limit the time to check fluid level in the Z06. Although it indicates allow 20 minutes max where the C7 says check within 10 minutes: “The engine oil level must be checked when the engine is warm. Under normal operating conditions, the oil pan under the engine does not store any oil. If the vehicle has been parked for an extended period without the engine being started, some oil will seep back into the oil pan, reducing the amount of oil held in the dry sump tank and there could be no engine oil at all showing on the dipstick. This is normal since the dipstick is designed to read engine oil level only after the engine has run long enough to reach normal operating temperature.
1. To obtain an accurate engine oil level reading, warm up the engine to at least175°F (80°C).
3. Wait at least five minutes (but not more than 20 minutes) to allow oil to drain and settle in the engine.”
I don’t know but this info from a 2007 Owner’s Manual provides an explanation of why you must limit the time to check fluid level in the Z06. Although it indicates allow 20 minutes max where the C7 says check within 10 minutes: “The engine oil level must be checked when the engine is warm. Under normal operating conditions, the oil pan under the engine does not store any oil. If the vehicle has been parked for an extended period without the engine being started, some oil will seep back into the oil pan, reducing the amount of oil held in the dry sump tank and there could be no engine oil at all showing on the dipstick. This is normal since the dipstick is designed to read engine oil level only after the engine has run long enough to reach normal operating temperature.
1. To obtain an accurate engine oil level reading, warm up the engine to at least175°F (80°C).
3. Wait at least five minutes (but not more than 20 minutes) to allow oil to drain and settle in the engine.”
From a straight forward point of view it only stands to reason the C6 ZO6/Grand Sports would have the same problem unless something is different on the LT1 system. In that case whatever the difference is surely the cause of the problem...from a simple perspective anyway.
BTW - I traded a 2012 Grand Sport for my C7 Stingray, never had any problems with the oil system.
