Audi s8 2007 coolant into oil

A8 All/ S8 All
#1

Hey guys so recently got a high mileage s8 v10. It has about 170k on it and yes i knew the engine would be a issue but i mainly got it for the body and I planned to swap the engine eventually from the one in my old s6 eventually. The car was running smooth and everything so I figured I’d enjoy it.

So pretty much what’s happening is the coolant in the expansion tank started going down and I checked the oil and it was milky and all the way up to the max. Prior to this the oil was just above min so it seems like all the coolant went directly into the oil. There is no smoking or anything from the exhaust or smell of coolant so I’m not too sure if it’s a headgasket

Today I just put some water in the expansion tank and pressure tested it and It started immediately dropping as soon as I pumped it. I did manage to get it to 0.5 bars and I did hear a air noise coming from like the pcv I’m not too sure.

I have no idea if it’s a headgasket issue or the coolant pipes running through the timing covers are leaking or if it’s the oil cooler.

If anyone has any idea I appreciate it.

1 Like
#2

If you are hearing hissing from PCV area, maybe the pipe connecting the PCV with the intake has failed internally? It has coolant lines connected to it.

#3

I capped it off and I connected the two lines of coolant to each other and it still sounds like some sort of hissing

#4

I did drain the oil earlier today and the amount of coolant that was inside of it was insane it’s like no gasket exists between coolant and oil. A giant milkshake

#5

Therefore, maybe coolant passage pipe orings in the backs of the heads failed?

#6

That’s my current assumption

#7

I just want to see if is anything else before I go changing that but I guess it’s process of elimination

#8

Do you know if i can change them with engine in the car or at least tilt the engine

#9

No clue about the S8, impossible in the S6

#10

I’m pretty sure I can tilt the engine forward to do it. Do you think I should try changing that or should I flat out pull it and rebuild the engine entirely

#11

It really depends if you want to invest in that engine or not. I’d say a little experiment with trying to do it on the car ain’t necessarily a bad thing, considering you already have a history of pulling that engine and you can sort it out if something goes wrong. Imo going with unexplored shortcuts in order to do some job is mostly unadvisable to people who depend on doing something that might go south, and don’t have ability to do the job normal way.

Long story short, I’d say go for it, you can always pull the engine later if needed.

1 Like
#12

I managed to remove 2 front subfrsme bolts and loosen the rear 2 and tilt the engine downward and so far I removed the timing cover on the driver side and it was milky as hell. The gaskets weren’t rubber it was plastic and didn’t look like it was sealing shit. The culprit could be these tubes. Tomorrow I’ll try to do the other side but the wires are all in the way and most likely I’ll have to unhook all that fun stuff

Ps it took me only 2ish hours to do and I started very late into the day

1 Like
#13

Can you post pics? interesting

#14

Yes I have to take some but I did lower it without removing the front and then I realized putting those timing covers back on would be insane so I removed he front to lower it and bit more to have room