1996 911/993 Turbo Dumping oil

Fastlane · 05-30-2007, 07:07 AM

I recently replaced both turbo's on this car. Starts fine but there is alot of oil in the intake system ie. turbo piping. When driving it alot of smoke is coming out the exhaust like a james bond movie.

can anyone help me figure out where it is dumping the oil or why it's doing that i would appreciate any idea's

Fastlane · 05-30-2007, 11:40 AM

someone please

Don Plumley · Don Plumley's Garage

What's the oil level when the car is hot?

JasonAndreas · 05-30-2007, 11:20 PM

Is there any chance you also replaced the oil filter? The 993TT requires a genuine OE Porsche (written on the side of the box and purchased at a dealership) oil filter. The OEM Mahle filters do not work properly with the 993TT and lead to the exact problem you're experiencing.

mmastro · 05-31-2007, 07:25 AM

Did you have the turbocharger(s) oil supply lines fitted with the oneway check valves? This virtually eliminates the smokey turbo problem.

As for the oil in the intake...how old/what's the mileage on your turbos? Maybe the seals are bad and you are getting oil into the inake side of the turbo and it get "rammed" into the intake system? I don't know. And like Don said, how high is your oil level? I can only speak of my 77 930, but it likes to be ~3/4 of a quart low for street and ~1.5 quarts low on the track. (I'd have an intercooler full of oil otherwise.)

Larry Marshall · 12-03-2008, 08:22 AM

First Fix: I have a 97 TurboS and experienced the problem over a year ago. I searched the net and found a couple of pieces of info that led me to a shop in S CA that developed a kit for the oil return lines to the drip boxes. They no longer make the kit. I found another shop in the same area that makes a kit for the input lines to the turbos, purchased it , installed it (a really full day) and once the build up of oil was eliminated the car stopped smoking. The kit includes 996 type check valves, 993's don't have them. Seems someone figured out there was a problem and fixed it in the later model???
Second Fix: Stored the car for 6 months and found oil leaks under both rear corners of the car upon my return. Prepared the car for start up and again lots of smoke. Checked the drip boxes and found them to be almost full. Suspected problem to be in return lines. More research on the net brought me back to the possible need for another kit. Found a real nice Tech that remembered a factory bulletin way back that instructed shops to hand tighten the engine case oil filter and then tighten with a wrench 1/4 turn. Changed the oil, filters and 1/4 turn solution and the car runs the way it should.
Issues: If you overtighten the case filter it crushes a check valve in the filter and the drip boxes fill up from the case return lines.. The 993s need check valves in the input lines especially if the car is not driven regularly. You probably should use Porsche oil filters (not mahles) and never over fill when changing oil.
If you need any additional info my email is ovh@att.net. Larry