Major oil leak at rear of engine!

[fiverpuller]

OK...I did something really stupid and started my truck without a crankcase vent. I plugged the valley pan vent with turbo return line and forgot to swap my banks cdr adapter on the IP cover (got way too excited once that batts where hooked up). So when I shut the engine off there was a hissing sound with oil dripping everywhere. I let it sit over night and fired it back up today (with oil filler cap off) to look for leaks. Sure enough oil was pouring down the rear of the engine onto the tranny...all over the firewall and turbo and onto the ground. There was also a slight hissing sound like air was escaping somewhere. It seems like it is coming out of the rear of the valley pan. So I pulled apart the 7.3 I plan to rebuild and I don't see how that much oil can come out of there. Any other gaskets back there I could have "blown" out causing it to leak this much oil?

One theory I have is the turbo feed line...but I have good oil psi (inline) when it was running. And the hissing noise has baffled me. I will take that off and check it next with a little pressure from the compressor.

 

[towcat]

oil pressure switch still in its stock location? That's the only oil related item on the back of the motor with a small orifice to "hiss"

 

[fiverpuller]

Switch or gauge sender? The sender is inline with the turbo feed line. It could be that or the lines...I will have to test it all tomorrow. If such a thing could hiss it must be that.

 

[towcat]

what did you do with the switch located at the back of the block? did you cap off the opening if you removed the switch/sender?

 

[Agnem]

Based on your descrption of the turbo and firewall being coated, I'd guess your problem lies in the turbo return or drain tube. Possibly the gasket where the drain tube is fitted to either the valley pan, or the bottom of the turbo has given out. Very sorry to hear you made a boo boo. At least you can't blame the truck. :draw

 

[fiverpuller]

what did you do with the switch located at the back of the block? did you cap off the opening if you removed the switch/sender?

I swapped all parts from other motor. Plugged the original sender port in the block and got oil pressure from a side port above the oil filter head.

I looked/felt around the turbo drain area and didn't feel anything out of place. I think I can get that stuff apart without removing turbo. Maybe my valley pan isn't draining good enough? I didn't punch any extra holes because the Banks install manual did not say to. Maybe if I can get in there with a funnel I will try the drain test.

 

[fiverpuller]

It sure seems like the oil is coming from the rear of the valley pan...where there was some silicone sealant looking blown out. Is there really much oil flinging around back there to leave a 12" puddle after 3 minutes of running? If nothing else it could be where the hissing is coming from. Just for piece of mind I am going to try and remove and inspect the intake/valley pan with the turbo in place. Is the valley pan reusable? I ask because on the 7.3 motor the pan came out clean with all gaskets intact.

 

[argve]

No the valley pan is not reusable. I suspect you can reuse it but I would not expect it to fully seal with a turbo strapped on top (it's holding back compressed air).