5.2 leaking oil - UPDATE, needs engine out

A6 All/ S6 All
#1

I posted a while ago asking for advice about an oil leak on my 2006 Audi S6. Since it’s been so long I thought it would be easier to start a quick thread with an update.

The crankcase breather system on the car was found to be faulty. It seems that the car released pressure by spewing oil from every orifice. When we first worked on the car the leak seemed to be mainly from the front of the engine. The intake manifold was removed and we replaced the failed O ring at the base of the oil filler housing, and the front crank seal. Whilst the manifold was off we did a carbon clean too, and I was happy to find I’ve got an upgraded manifold on the car ;D

Oil is still leaking. It’s not a major leak but it’s coming through between the engine and gearbox. We’ll be taking the engine out this weekend to replace the rear crank seal and do preventative maintenance. Am I right in thinking it’s not possible to drop the gearbox without removing the engine? Shame really as it would be quicker to just drop the box.

I’m planning to be there throughout the removal so should get some nice pics of the mayhem!! The sadist in me has been looking forward to this job. I think it was always inevitable.

#2

pictures will be great. It helps you and it helps the forum as they can get more and more of an idea on what things look like and how things really work.

As for the transmission you can totally drop the transmission with the motor still in the car. There is no reason why you would have to drop the motor to do the work your talking about

The work you are talking about is something called the rear main seal. Its the seal that goes around your crank shaft and it is a area that you can totally have leak if your PCV system is not working properly. I think this thread is a great idea because lots of people dont understand just why you need to be so on top of certian things maintenance wise on cars. When your pcv system went bad it took out a bunch of other seals.

Back to my point. The only reason you would pull the motor is to get to the starter to help get the transmission back on. The tq converter access is through the starter port and I think it might be eaiser to pull the motor to change the starter so that might be why they are pulling the motor. If you want see if you can get more information from them and we can give you any feedback if you are not sure. We can say yes or no if something dosent make sense

#3

In for pictures!

#4

Did you replace both oil filter housing o-rings? Front and rear?

Just wondering because I would hate to see someone pull the engine/transmission for a rear main seal when it is the oil filter housing seal leaking. I have seen it a lot on other models.

#5

We did a visual inspection under the car and it didn’t look possible to drop the gearbox because of the location of the cats - it looks like there’s too much to get in the way of it coming out. That was the only reason we thought it would be a full engine out job. But it sounds like the hard bit is getting the gearbox back on due to where the starter motor is? It would be preferable to just drop the box, change the seal and see if the leak goes away. If you could give any pointers as to how to drop the box that’d be great :slight_smile:

When we took the intake manifold off the O ring that we changed was on top of the engine and the rear of it. It was clearly leaking (no 14 on the diagram). I’m pretty happy this area is sound now, and the leak is only coming through the gap where the engine and gearbox meet. It was all over the front to begin with but this is now dry.


http://i59.tinypic.com/zslkxi.jpg

#6

I sent you back a message.

It’s a though call on the motor. It just might make sense due to getting a better look over all the parts if

#7

Here are some pics of where I could see leaks inspecting underneath the car; around the oil sensor and the join between the gearbox and the engine.

https://8m2ywg.bl3301.livefilestore.com/y3m-2S7SQeIt41jaSd5KLattKB0jj6YKT46zbemWbbLKywgw8QKVvwjzzR1d8dH6_xt0uNDhcb2dEvsp5aN3fWSEnKtb51LfE-C9zbDEEfTiL69SYZdvtdrNtCUq74waCllEEQgJlVPCATQlZMKz9hQWqvnMdrnL9XZuh-eIrITqvs?width=2688&height=1520&cropmode=none

https://8s2ywg.bl3301.livefilestore.com/y3mOq2bAy2LZoyLEbPzX7LtU6byCPEZ18XToyM46ec2lQX5Vciw1SeOGWI1GT-JZfuOs2V_50P43qQXKtPL8LISDQrmpmBfDlyIOn18EifDERRA2QPDXHYzROw5O1p3wiHvync_pE6pbk4-ShV2NFIaO2X1aKZZLdlbmKc5UPCNYco?width=2688&height=1520&cropmode=none

With the front end off. I’ve had the front crankcase seal replaced months ago and you can see the spray from where the oil had been spewing:

https://8c1nzw.bl3301.livefilestore.com/y3m8xn9cJ5TQk-QYgFlsI0PbrMlOPy_8PYDjIoRNiKItPvr3FzUzDggdV6ap9N5XEFlGSzDttaFvASSIbfYYj7PLZMKt9jTnurfrGwZhVMGQuWNaMW-X7ZMxcqqPll5W7IQX-IaPRG5_PNlnrsc77cvdgXcalr5l24jLkdCfxxX9lQ?width=2688&height=1520&cropmode=none

https://982ywg.bl3301.livefilestore.com/y3muX4KQq5gZaavYZXmt0A36M-9J0iY1FP92Y9za4k9GyrJ6SQlz0SNr11IC6ml9V4IQ9xzfpp8uZigNw6OOcssy9TSbWGx3nKeT4IGi5HWTTLzTGi5k4H2y9HdGj6-gnQgaoKnmMiL4eMQCdaY9aCE8LpHPiTEQsyv9hXqUOuQwkU?width=2688&height=1520&cropmode=none

https://pm0x5g.bl3301.livefilestore.com/y3mfyO47t8jI_Ilc8Mzs2Sz9-bnrKeR1RzJw7bBJ5bjnd3i4Rj4plaojWvypbXvc_LTu58NdIbE9ZQ19XszU2dD1mphbnWL3752HtvaEke5aF-9fdmJw-lpMh61PLXdjnzcbey9dI6lKRKFisgA5uCwD9RXkpBr-9evJQRYhy0CsJw?width=2688&height=1520&cropmode=none

We’ve inspected the back of the engine and will be replacing the rear crank seal and a few bits of hoses. The total value of parts is around £100 so far. The timing chain will be inspected and I’ll try get a picture of that. Then it’ll be a case of cleaning the engine up and sticking it back in the car.

#8

Wow your doing this at a good time. I have seem much much worse but you can see the car would benifit from a good once over. And the money you have into the project right now is very small. If you havent already pull the intake and check for carbon there. Also might not be a bad idea to pull the injectors out and send them out to get flow matched and tested. that is one of the big issues that people see with these cars. Also if you havent already get the JHM intake spacers its a big help with these cars and all the heat. Not to mention it helps give a little performance as well

#9

Nice work, this is a bag and complex motor, still looks beautiful out of the car though. I think you will be very happy once done :slight_smile:

#10

After looking over the pictures again. When you pull the intake manifold make sure to look at the oil filter housing base for thoese seals. The front of the motor has a lot of oil collection on the driver side front. That usually says the oil filter seals are leaking and oil is running down the galley and then the front of the motor