locobob

I am having a problem with oil loss, about 5 quarts in the last month. The car doesn't seem to be burning oil. I haven't noticed any more smoke than usual. There are no leaks under the car. I did notice that the tailpipes will sometimes spray a fine black liquid mist. Doesn't happen all the time, usually I see it on a cold start up. At first I thought it was carbon deposits from the tailpipes mixed with condensation but then I found the oil level kept going down. How could that much oil get into the exaust without getting burned in the combustion chamber? Any idea whats causing this problem? The car is a 91, fairly stock and I am using Mobil 1 10-30.


[Modified by locobob, 3:27 AM 7/7/2002]

vader86

are you seeing any blue smoke coming out of the exhaust?

locobob

I get a little wisp of smoke on hard acceleration sometimes but that was present before I started losing oil.

Rolin

I'm actually losing oil too. Same symptoms... no leak, no smoke (that I can tell) coming from the exhaust and 3 quarts in 3 months. Very interested in getting some feedback... :confused:


[Modified by Rolin, 6:52 AM 7/7/2002]

steve_usa_2000

Here are a couple of things to look at. I will try to find some more possible. Also anyone else out there have any ideas?


1. Check for oil leaks especially around the oil pan. Common problem for the oil pan screws to become loose on ZR1’s.
Fix: In most cases tightening the bolts will work, some are hard to get at.

2. Check the Oil lines running from the oil cooler to the front of the engine. They maybe leaking where they connect into the block or at the connection where the rubber meets the metal line.
Fix: Replace with newer lines from GM.

3. Oil leak from header studs.
Fix: May have to remove, coat bolts to keep from leaking and retighten.


Good Luck! :seeya

ZR1

The LT5 is an oil user. They had a devil of a time with windage on this thing. If you run your car hard it is not terribly unusual to burn a bit more oil than you are used to. However, 5 quarts in 5 months is a bit much unless you are just running the **** out of it. Get a compression check.

BiZ

How does the oil loss equate to mileage? I use about a quart every 800-1000 miles. I drive my car everyday. 12000 miles in 10 months, some hard some easy. Does this sound about right for oil consumption?

VetteBabe1

Mine does the same or thereabouts. But I have a known leak, seemingly coming from the passenger side of the motor. Have not investigated in depth but hope it's not too serious. I had heard that the LT5 will and has to use oil because the cylinder walls are lubricated. Is this so?

ZR1

That rate of oil loss is not at all out of the ordinary.

BiZ

That's what I wanted to hear. The only known leak I had was a power steering hose. I have taken care of that and washed the underside of the car. Since then it remains clean and dry under there. I have always heard that a healthy motor will use oil.