Where is the oil going???

[Huicho417]

I am trying to figure out where my oil is going. Not a drop of oil on the driveway when I park the car for several days. When I check underneath, there is a drop that looks like its coming out of the transmission inspection port. Could this be from the rear main seal? If so, would it only leak when driving? I recently added an oil catch can because I thought I may have excessive blowy by sucking oil vapors out. I changed the oil this weekend after about four months (i only drive the car every other week around town) and the can had 90 milliliters in it. Does this sound excessive? I also just added an ME Wagner dual flow adjustable PCV valve just in case I am building too much crankcase pressure pushing oil past the seals. I did notice oil residue around the valve cover filler cap and bolts. Only time will tell is this alleviates the issue.

I forgot to mention that the car does not smoke at all, idling or when cruising. Has anyone dealt with a similar situation?

 

[pnora]

How much are you adding? I will just about bet if you have someone drive it and you follow you will see blue out the pipes. I am pretty sure by all your posts you have a internal engine problem. One cracked second ring or wore out rings. A leak down test may show the problem.

 

[Kern Dog]

First of all, few of the members in the US may know what a "milliliter" is!
Secondly, the oil residue at the transmission bell housing area is most likely a rear main seal although the back of the engine does have pipe plugs threaded in as seen here:

 

[Huicho417]

I own a small camera that i can mount on the rear of the car while I drive. I will record next time I drive and see if the blue smoke is there. Thank you for the leak down test suggestion, I will do that this weekend if time permits.

 

[dadsbee]

9 times out of 10 oil dripping off the bell housing or transmission converter shield is a leaking valve cover!

 

[pnora]

First of all, few of the members in the US may know what a "milliliter" is!
Secondly, the oil residue at the transmission bell housing area is most likely a rear main seal although the back of the engine does have pipe plugs threaded in as seen here:

View attachment 1426137

I would assume he is adding oil. That's why I asked how much. As far as a milliliter goes if thats all he is using he should have no concerns.

 

[Huicho417]

ahahah, you have a good point on unit of measurement comment.

I actually replaced the threaded pipe plugs when I had the engine out to clean the water jacket.

 

[Huicho417]

i added a quart in between the oil changes.

 

[Huicho417]

i did do a compression check and the results where well within normal as listed in the service manual.

 

[pnora]

i added a quart in between the oil changes.

How many miles?

 

[Bee1971]

Did he mention what car what engine

If a Big Block

Valley Pan - Intake Manifold Sucking Oil Possible

 

[Huicho417]

not sure on the mileage, when I purchased the vehicle the odometer worm gears were so worn that the mileage was turning.

 

[Huicho417]

sorry, 1967 coronet 440 with a LA318.


The more I think about it and pictures I look at from working on the car that small drop of oil under the bell housing has always been there.

 

[Huicho417]

really appreciate everyone's input on this.

 

[Huicho417]

Below are links to videos I was able to take with my action camera, of my morning drive to drop of kids, then to work. Apologies for the camera being turned sideways. One is the cold start and the second a continuation of the drive. I did not see any blue smoke.

 

[1STMP]

I am trying to figure out where my oil is going. Not a drop of oil on the driveway when I park the car for several days. When I check underneath, there is a drop that looks like its coming out of the transmission inspection port. Could this be from the rear main seal? If so, would it only leak when driving? I recently added an oil catch can because I thought I may have excessive blowy by sucking oil vapors out. I changed the oil this weekend after about four months (i only drive the car every other week around town) and the can had 90 milliliters in it. Does this sound excessive? I also just added an ME Wagner dual flow adjustable PCV valve just in case I am building too much crankcase pressure pushing oil past the seals. I did notice oil residue around the valve cover filler cap and bolts. Only time will tell is this alleviates the issue.

I forgot to mention that the car does not smoke at all, idling or when cruising. Has anyone dealt with a similar situation?

3 ounces of oil loss is not excessive
with driving it half a month with the
other 2 weeks sitting. Is there a high
level of humidity where you live?
Your oil loss is negligible if you've
no oil spots on your driveway as
far as the drop on the bell housing
goes, and is probably coming from
the breather cap.
Pull your oil fill cap on the valve
cover and inspect for slight
doscolorization of the oil (white
foam, or very small bubbles)
and check for condensation
contamination. Oil will evaporate
with that condensation when the
engine reaches normal temps, and
it won't show as white smoke out
of the tailpipes, but sometimes
does show as water drops. Also,
the inside of the tailpipes will have
an excessive oily film.