996 Oil Leaks

A buddy of mine brought by his 996 that is having trouble containing it’s oil, lol. Every time he drives the car, he gets out and smells that familiar smell of oil burning off the engine. It was time to get it taken care of.

One of the most common sources of oil leaks in the M96 motors are the spark plug tube seals. There is an inner and outer o ring on the tube that will leak over time. A leak at the inner o-ring will usually lead to oil on the spark plug. A leak at the outer o-ring will run down the side of the motor and burn off on the headers.

Up and ready to rock.

I should have taken a picture before I started cleaning. The side of the motor was black…..black with a thick layer of goo!

By the #1 cylinder, you can see the oil trail starting up by the coil pack.

And on the back of the motor, we likely have an issue with the OAS bellows or the OAS leaking.

All over the bottom of the motor

After a little scrubbing, and 5 cans of cleaner, I am high, the shop supervisor is high, but the motor looks a little cleaner. Proper ventilation. It is too late for me, but you can save yourselves.

After observing the M96 motors for the last couple years, I have come to recommend that you do your spark plug tube seals whenever you replace your spark plugs. The parts are cheap, and there really isn’t but a tiny amount of extra labor to replace them. I usually just include it in the spark plug labor time.

Here is the #3 cylinder since we are doing them all. After removing the coilpack, you can see the tube (inside is the spark plug).

Insert special tool KEWP.9033.54b

And pull out the tube.

And this is what it looks like. Be sure to inspect the oil tubes as well for cracks, typically you don’t have to replace them, but be aware that I have seen them cracked before.

Clean it up and put on the new seals.

Again, Wurth Silicone Lubricating Compound comes in handy again. If you try and put them in dry, you will tear the o-rings. Lubrication the o-rings and it will pop right into place.

Here you can see the passageway between the outer cam cover and the camhousing that has to be sealed off from oil, hence the tube.

Then I went after replacing the OAS bellows. We will start there since it is easy and see if that oil leak slows down. If it doesn’t, we will have to pull the entire OAS out and replace it.

And everything cleaned up and ready to go. With the motor clean (well, as clean as my brain cells can handle), we can monitor it easier for any additional leaks. Hopefully we got them all, but no sense giving back a dirty motor.

996AOSBellowsBoxsterOASOil LeakPorscheSPark Plug Tube Seals

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peter blackburn

October 25, 2013 at 5:23 AM

Hi ,
Where did yoy buy the tool for removing the oil tube it looks like a transome plug?

Many thanks peter


    October 28, 2013 at 7:18 PM

    Hi Peter,

    It is a highly customized special tool. You are correct….it is a transome plug.

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