1991 240 Sedan, 150k miles

The PVC system was cleaned and redone entirely just last year, new flame trap and such. Theres a leak at the back of the engine that only happens after drive, its fine when warm and running, or cold and sitting. I do not recall it leaking after the PVC job, only recently.

What could be leaking, rear Crankshaft seal? Oil pan? Distributor?
I just had it changed at a shop and they think it was coming from the distributor, even though thats mounted toward the front I believe.

The puddle itself will usually be 2-finger tips wide, right under the U-joint in the exhaust, around oil drain bolt.

 

Sounds like the rear crank seal. Usually happens from PCV plugged . If it is you need to remove the transmission. Are you sure it isn't the rear transmission seal.

 

If it were the transmission seal wouldn't it leak transmission fluid?

EDIT: I did try the oil cap trick, shook everywhere (engine vibrations) but I dont recall there being that much blow by, I'll be taking apart the flame trap this weekend to look it over.

 

Lev was referring to the rear main engine seal. It keeps engine oil from leaking out where the crankshaft exits the engine.

If it is the rear main engine seal, you would only see oil below the car where the engine and transmission are bolted together. If you see oil higher-up then the source of the leak is something else. If there is significant pressure buildup in the crankcase, many times the rear cam plug will blow out. If this happens the engine will leak oil out the rear of the head. You would see a lot of oil on the firewall.

When you serviced the flametrap did you check the oil separator box to see if it was clogged?

 

wash the whole engine and transmission and underside down with Gunk or similar. add a packet of UV dye to the oil, drive a few miles, park car in dark shady place, and use a UV light to look for seepage, you should find the source of your leak pretty quickly.

 

The tests will have to wait, I just did something really stupid.

I removed the quite clogged flame trap screen and reinstalled the trap, broke a small dry rotted hose beside the trap that leads to a plastic nipple.

Tried trimming and refitting the hose, now oil sprays out on top from that or the flame trap area. The hose itself broke on a lower area, its done.

The hose Im referring to is not apart of the flame trap, its a small hose that runs near it.
Note: Ignore the flame trap nipple, that hose is fine and was attached when I tried running the car.

 

Are you sure it is oil as it looks like a fuel line. Maybe the return line.

 

Just checked, thst is a fuel line and based off the smell, it was gas spraying everywhere.

I should note the car struggled to build fuel pressure during testing. Niw I just need to find where the other end is for the hose.

 

Looks like the main fuel line that feeds into the fuel rail... You cannot use any fuel line to replace it, pressure is too high... New, I don't know, must be pricey, but what choice is there? May be get it used if there's a p -n-pull place near you. The little plastic flame trap seat is easily available.
So, was that the leak source, fuel, not oil?

 

The original source was oil, the new "puke-leak" is gasoline. The nearest PnP doesnt let customers in (you just guess and Pray they remove the correct part). Given this is fuel related, I'm willing to pay extra money if it means a better hose, safety means more to me than saving $3.

http://ww2.justanswer.com/uploads/en...or_picture.jpg
Id you look at this picture theres a small hose on the lower left between the injectors, I'm thinking (and hoping) thats what I broke.

 

That fuel line runs from the fuel rail ( next to #4 injector) to the cold start injector ( where my finger is in pic) underneath the intake manifold.

 

I can read the numbering "912 W 8825" on the fuel line in the picture on previous post. Those pictured parts are from a '89 740 with a NA b230f.

 

Hopefully thats all that I need then, thank you for the pics. It'd be nice to know that the injector works!

Just some notes on the oil leak, the only oil I could find back there were little bits around the cap, the firewall and the area back there were fine.

 

The fuel leak is fixed so far if temporarily, used a piece of yellow hose with clamps from the local O'Reilys, spotted a leak in one of the low pressure lines that we fixed as well (I never touched this line, it was just dry rotted).

So yes it was the cold injector line that I screwed up, I'll keep my eye out for any oil leaks.