Hot oil/Cold Oil, to much/to little

Dave Colangelo · Dave Colangelo's Garage

So I have had what I though was some what of an oil leak for some time. Basically when ever the oil heats up and I pull in from a long drive I get about 1/4 of a cup of oil run down the side of the tank and drip on to the floor. When i put oil in I usualy check the dipstick when the engine is cold. It always read low and I would put in more until it got around the full point all cold oil. When i did this the oil gauge also read full. But as a result the leak would ensue. This leek would continue for days every time I drove it until it eventual would stop. I would then put more oil in and do it all over again.

Today a fellow pelican told me to check the oil when it was hot, not cold. I knew i was running low and the oil pools are getting smaller, so i know im close to a bit of a fill. Any way, after our run I got home and right after cutting the engine i checked the oil. Note that on the way home the oil gauge was bouncing between reading full and a little under half. Upon checking the oil, its at Max on the dip stick, and a little over max on the other dipstick i had lying around dont ask why i have 2 but they are labeled differently ill post pics soon.

So does that mean that i dont have a leak and some thing was just over flowing, or that i have a leak and should tend to it even though im holding the right amount of oil. Is there some kind of over flow mechanism on the tank?

Depending on posts i may or may not drop the oil tank.

Regards
Dave

Dave Colangelo · Dave Colangelo's Garage

One there thing i should mention. I changed the gasket on oil level sender about 2 months ago. When i did this i pulled the sender out, attached to it was a dip stick that some one had dropped in the tank, hence the 2 dip sticks. Any way, the arm could very well be bent in a way it should not be so the level sender may not read what it should.

Regards
Dave

E Sully · E Sully's Garage

I wish I could have made the drive today and met some of you guys. I'm not far from Bear Mountain.
The oil level needs to be done with the engine warm and running at idle due to the dry sump design. It is possible that you are over filled. The gauge is not accurate. It should never be filled over the half way mark on the dipstick. There have been a few different dipsticks depending on year and changes in the oil tank. Your leak might only be from the gasket at the oil level sender on the tank.

Dave Colangelo · Dave Colangelo's Garage

the dip stick that i found in the tank has 2 sets of double dots, and the one that was in the car has the words min and max on it.

Regards
Dave

blucille · 12-23-2011, 12:29 PM

yup, always check oil with car warm, car running, and has been running for a few minutes, at a normal idle, on very flat ground....

the difference between warm and could is significant, probably equal to 1-2 quarts on the gauge or dipstick.

doubt you have an oil leak worth repairing, glad you didn't hurt anything running past full capacity.

once you get a feel for what warm, flat, and normal idle oil level looks like on your trusted dipstick, note where that level is on the gauge, and use that as a point of reference, but not as gospel as to what your oil level probably is.

LE

redstrosekNic · redstrosekNic's Garage

You need to check the oil with the engine at idle, and at operating temp. You are certainly over-filled with oil. My guess is that your tank was leaking at the oil level sender. If the oil level is above the sender, I would think you'd have quite a leak. Have you had lots of oil going into the intake?

Sorry Sonett, you must type faster than I do

E Sully · E Sully's Garage

Quote:

Originally Posted by Dave Colangelo

Any way, after our run I got home and right after cutting the engine i checked the oil.

Cutting the engine was a mistake, keep it running at idle. Look inside the fender well and see if it is coming from around the sending unit. If it is leaking there the gasket is just a small cork one, but a bit awkward to change, due to the twisting needed to get the sending unit and float out of the hole.
Maybe you can get someone to measure and post a picture of the correct dipstick for your year.

Porchcar guy · Porchcar guy's Garage

+1 on all the answers that tell you to check the oil level with the motor running at idle after about a minute. The engine should be up to normal operating temp...as in drive it for 20 minutes or so and make sure the car is on level ground. Open the oil filler..hear the idle change and then check it !! If the idle doesn't change...you have a another issue ....you have a vacuum leak somewhere.

JohnJL · 12-23-2011, 05:59 PM

Not only does it need to be running for a few minutes, it needs to be warmed up enough that your thermostat is open and flowing to whatever front cooler you have. Air pockets and funny drainage there can leave you thinking you are full, but you are low when it warms up again.

You shouldn't ever be leaking oil out the tank. Check your sender gasket for leaks.

Canada Kev · 12-23-2011, 07:20 PM

When you're driving down the road, your oil gauge will likely read EMPTY, unless it is defective or you have too much oil. If it is accurate, it would reflect the oil level in the tank only after idling on level ground for about 30 seconds. It then should stop wiggling around and become stable. Again, like everyone else has said, this is only after the engine oil is HOT, at full operating temperature.

Depending on where you live, at this time of year you might not even get up to full operating temperature after a lengthy drive. If this is the case, I wouldn't ever fill past the bottom line at the warmest temperature it reaches, maybe even less, depending on how warm it gets.

Joe Bob · Joe Bob's Garage

Might want to read up on how a dry sump works. I'm surprised you haven't killed all the 'skeeters in your neighborhood from the overfill getting sucked into your intake.....I'm guessing you have a good oil restrictor in the breather OR likely, the breather line is dumping onto the ground or a puke box is filled up.....

Check when HOT, running, on level ground. Oil level 1/2 between upper and lower amrks on the dip stick.

Hugh R · 12-23-2011, 08:02 PM

My understanding is that the only time the oil level gauge really means much of anything is when you're hot, idling on level ground. I suppose you could use it as some kind of oil level gauge after you understand the relationship between it and the dipstick on your car.

orange911 · 12-23-2011, 08:33 PM

Quote:

Originally Posted by Porchcar guy

+1 on all the answers that tell you to check the oil level with the motor running at idle after about a minute. The engine should be up to normal operating temp...as in drive it for 20 minutes or so and make sure the car is on level ground. Open the oil filler..hear the idle change and then check it !! If the idle doesn't change...you have a another issue ....you have a vacuum leak somewhere.

What do you mean the idle changes when you remove the cap. Please elaborate

Joe Bob · Joe Bob's Garage

The open oil cap simulates a vacuum leak.

Dave Colangelo · Dave Colangelo's Garage

Some updates,

So i ended up driving the car to jersey for a dinner party, the ride home was a solid hour which gave me time to get the engine up to temp. The temp was dead on in the middle, when i pulled in to the garage i let the car run so i could check the oil. The level meter was down on the bottom in the red and i was on level ground. The dipstick read full so i think the level sender is a bit bent. I know the gasket is not leaking because it was leaking and was replaced about 2 months ago.

Now for the interesting thing. When i removed the cap the idle did drop as it should which is good because that means i dont have a vacuum leak. Now does that mean that i dont have a tank leak either. My assumption is that a tank leak would be like a vacuum leak and create this idle dropping effect all the time. Or can tank leeks be small enough that they would not simulate a vacuum leak?

Regards
Dave

Joe Bob · Joe Bob's Garage

I'm kinda dim so I ask questions. Carbs or fuel injection? Can you see where the breather lines go? Got pics?

Dave Colangelo · Dave Colangelo's Garage

CFI, all stock 78 3.0 motor. The oil breather lines (are they the smaller lines that go in to the tank on the tube that comes off the main tank where you fill the oil up) Ill post some pics tomorrow.

Regards
Dave

DRACO A5OG · DRACO A5OG's Garage

a 1/4 cup really? do you see where it is leaking from?

Dave Colangelo · Dave Colangelo's Garage

Draco,

I could not see where the leak was, all i could see was that the oil dripped down the face of the tank and came from some where above where the tank kind of meets the body.

Regards
Dave

novadia · 10:46 PM

Hey Dave, had the same issues coming from that area in my car. Could be a few things. Loose hose connectors, hole in the oil tank, overflow, bad drain plug, etc. best thing to do is clean the area well and then track the origin. If you can make the trip to NJ I wouldn't mind wrenching with you for a while to find the leak. I live right over the GW in Leonia. Give me a call.

Neil