Today I found a hole underneath the car dripping oil.
Its in the center of a dished like plate bolted right behind the oil pan. About a 1/2" hole
I have no idea what the part is or if the hole is suppose to be there.
It doesnt have threads so im stumped
The car is a 73 Challenger with the 340 4brl.

 

the only thing that comes to mind is the inspection cover for the transmission. If it is dripping oil, red in color, on an automatic transmission it means you probably need a new torque converter and pump seal. If it is just a tiny bit like a smear or a single drop that isnt bad. If its a cup or more it means the tube on the torque converter cracked. That happens when people slam the car into gear on a cold transmission. There is places that rebuild torque converters and basically weld a new tube in. Its cheaper than a whole new coverter but thats up to you.

That said if the oil is black in color its not the transmission but the engine that's leaking oil probably from the oil sending unit up top of the engine. If you look behind with a trouble light you will see a puddle of oil sitting there. It tends to drip down in that area.

If the fluid is green, brown,or orange its antifreeze and your frost plugs need replacing which is a big job. If the rear are going it means they all need replacing.

 

Thank you for the reply, Its a 4 speed does that matter?
I bet your right inspection hole. I could barely see something in the hole.
The car is so hard to get under I had to take pictures with a camera to see anything in it.
Sadly the underneath of the car is pretty much covered in oil.
Any idea what would cause over 3 gallons of oil/water to drain from the oil pan?
The car fires right up but Im scared to start it after noticing this.

 

3 gallons of oil from the oil pan would mean you ran over something and punched a hole in it OR someone didn't tighten the drain plug on the oil pan. Dont run the engine get underthere with some rags and go looking. I would suggest throwing down some cat litter on the mess and using an old large cardboard box to lay on. A 4 speed has gear lube in it and would not drain out the front of the bellhousing.

 

the only "dish like" pan I can think of just behind the oil pan would be the dust cover. The dust cover bolts to the bell housing to keep crud out of the clutch area. Mine doesn't have a dust cover on it So i can't tell you if it's supposed to have any kind of hole in it or not. But there shouldn't be any kind of fluids coming from it. Like Jacilynn said it's probably either antifreeze from a freeze plug (and yes they are a royal pain to fix). I don't know if there is any way for gear oil to leak out of the front of the trans on a 4 speed or not. Not sure how a dust cover is set up on a small block but you could have tore up the rear main seal pretty good and a lot of oil is draining down the side of the dust cover and dripping when it hits that hole, or its draining directly into the dust cover and coming out of that hole.

 

Please bear with me I only have simple mechanic skills. Sorry I wasnt very clear. There was only a small puddle of oil on the floor. but just about every part under the car is splattered with oil. The oil may not have been coming from the hole in the dust cover, but since its shape it ran to the center and dripped.(not much)
I noticed barely any oil on the dipstick so I put a little bit in about 1/4 quart for now and later I saw about the same amount had fell to the floor.
I went to drain the oil and thinking there wasnt much in it was surprised to have it gush out of the oil pan into my drain pan and was filling up quick.
I filled a 5 gallon bucket 3/4 way full with oil/gas mixture.
So far I havent done anything else but put a new oil filter on.
I think I need to replace the fuel pump now and fill it back up with oil and see if I get gas in it again.

 

Are you sure it's gas in the oil and not water? Sometimes oil will smell like gas because all vehicles get trace amounts of fuel in the oil. Very minute amounts get passed the piston rings and if the oil is in the car long enough it will begin to smell like gas. If your seeing white or milky drops floating around in the oil its water and you've either got a blown head gasket or a cracked head. It's possible for large amounts of gas to get into oil (what it looks like I'm not sure never really seen it) but it's usually from an engine having very worn piston rings and cylinder walls, and then getting heavily flooded with gas. I'd say the head gasket is more of a possibility though. Not sure if a bad fuel pump will let gas get into the engine. I've never had experience with it. But as far as I know when a fuel pump goes bad it just kinda stops workin or acting funny. Might make sure of it before you put oil back in it. May save you from wasting an extra 40 or 50 bucks on oil. Also if you've got a blown head gasket and keep driving the car like that, it's possible the head gasket could get worse and start letting water into the cylinders. If enough gets in and your driving the car, it could possibly bend a rod, bust the piston, or crack the cylinder wall. Water doesn't compress and can really screw you over hard.

 

No white droplets on the removed oil but still a fairly weak gassy smell considering the amount.
I read somewhere that if the fuel pump diaphram gets a crack it will send gas straight to the oil pan. Not sure if its true but it made me feel better thinking I just needed a fuel pump.
I sure hope its not bad rings or gaskets.
Radiator is still full does that help me?

 

Ok if it's just the gas smell your fine. Any water in the oil would be obvious. It goes to the top after setting for a minute. Oil is heavier. And it just depends on the leak if the radiator will be full. Usually they just crack enough to get water in a cylinder and make it run like crap and you'll see a little bit of water on the dip stick.

 

Deffinently not driving it til I know its in good shape.
Very sentimental car, I got for my 18th from my dad who bought it when he was 18.
I drove it for about 8 years no problems at all until I hosed the motor off for a cleaning.
I did take care not to get water in the carb, but it didnt run the same after that. Ive had it in my garage for the past 4 years because of now being occupied with wife and kids.

 

Rocknroll Ive seen holley carbs dump fuel into engines while sitting and when the gas is tarnish the oil wreaks so much I get an instant migraine. And yes a bad fuel pump diaphram can leak into the engine although usually they **** oil out the side instead.

If the engine had 3/4 of a 5 gallon pail that would be about 4 gallons of oil which is just about right.

It would help to know what engine is in the thing but I suspect that the car has an oil guage.

On the back of the engine on the passenger side near the firewall you will probably see a puddle of black oil. That means the sending unit, if equipped, is leaking oil which is not unheard off. There is a few different types. There is the small shallow one for an idiot light on the dash. There is a larger copper colored one for a guage. If someone installed a mechanical guage there will be a small brass fitting with a small white plastic line on it.

If you used a steam cleaner to clean off the engine of even a high pressure washer you could have busted the plastic line and it is pissing oil all over. Remove the fitting and line and put in a proper sending unit depending on whether your car came with idiot light or guage in dash.

They do make electronic oil guages for after market that use the same big cadium plated sensor that chrysler used. Not to easy to get a hold of.

The small white plastic line can be fixed by being shortened depending on the type of fitting. Some are a compression fiting where you just put an outside compression sleeve and an inside sleeve then retighten.

 

Am i reading this correctly? 4 GALLONS of oil? That's a lot of oil to not read on the dipstick, and certainly enough to make it not run properly,
with that much fluid in the crankcase it should be looking for any possible place to escape from.
and yes the manual trans dust shield does have a hole in the bottom.

 

I thought cars only required around 5 quartz of oil?
Its a 340 engine and does have a holley carb.
The oil guage in the dash doesnt work but there is a oil/temp guage
mounted right underneath the stereo that does work. Pressure read only 20psi
before I checked/drained the oil.
I looked on the back of the engine where you say a puddle should be but the engine isnt flat there to hold a puddle but I do see it has a single cooper line with a brass fitting running into the car to the oil/temp guage.
As I said I use to have carb troubles, flooding it to where the garage reaked of gas, I was also improperly adjusting air/fuel mixture screws.
I had the carb sent off last year for rebuild and was told air/fuel are set right now.

 

Not quite correct, it uses SAE 140 gear oil under normal conditions, but standard ATF can also be used in extreme cold climates. I have also used it when there is too much gear noise using 140. If over filled it will leak out the front.

 

Your 340 should take 5 QUARTS of oil with a new filter. The copper tube is running to a mechanical gauge inside the car. 20 PSI at idle in an untouched 73 motor is about right, it should climb to about 55 PSI at speed.

 

Ops my bad I got gallons confused with quarts. Don't use those in canada sorry.

4 gallons in an engine is bad. Not the first I have seen though but it usually leaks from all over when that happens.

cant load picture for some reason.

 

How would you over fill a transmission that fills up to the edge of the hole in the side? Also atf is SAE 30 and the transmission would be noisy and take alot of wear.

 

This I would also like to know. Only way I know that it could be done would be filling it up before it is installed in the car and having the transmission on it's side while doing it. But from the sounds of it the transmission most likely has been in the car for a while and would be leaking long before now, I would think.

 

https://picasaweb.google.com/1135986...35600867904338



Maybe this will show

 

love the routing of the heater hoses lol.

not much help showing the back of the engine near firewall or underside actually.

 

I added more photos,hard to take pictures underneath so I didnt.
Pretty much everything underneath has oil on it so pinpointing a leak would be impossible i guess til I can start it up again. I like the idea of a steam cleaning it would be better than high pressure washing.
I think ill try a new fuel pump tommorow and then add my oil. see how that goes.