The RS6 was booked in for a scheduled service last Thursday the 23rd and to check out a coolant leak.
Outer CV boot, Both transmission mounts and a couple of other little things. The big problem was a coolant leak that was coming from within a housing on the drivers side front end of the motor. The problem? You can’t get the housing off due to the chassis rail being a hands width from the end of the housing. Audi workbook says “pull the engine”.
I gave the go ahead to start disassembling the front end. Chatting with the mechanic we both agreed that it would be worthwhile trying to at least drop the engine down as much as he could rather than pulling the whole thing out.
Swung by this afternoon to check out how he was going.
The engine has been dropped enough to gain access to all the bolts and allow enough room to remove the housing from the side of the block.
From the not so helpful photo above I’ve marked:
1: Cooler location,
3: Chassis Rail.
This diagram might be more helpful.
Let’s have a look inside the housing.
The oil cooler is a Modine 077117021Q. While the cooler seems to be structurally ok there is a fair amount of corrosion. The inside of the housing is also fairly corroded. Rather than chance it I’ve ordered a new housing assembly including a new oil cooler.
And, as usual, it appears that a cheap plastic part (i.e. suction jet pump) has caused me no end of grief. This is what’s left of the oil cooler water pipe (Part 13 in the above diagram).
After a bit of research I found, what some of the forum guys refer to as a “Bufkin pipe”. James Bufkin makes “Aluminium Oil Cooler pipes that replace the Plastic OEM pipe that is prone to break in Audi 4.2L V8 engines every 100,000 miles or so”. His aluminium pipe allegedly replaces part numbers 077115441 and 077117441A. From what I could find, the water pipe’s part number is 077117411A and the seals are 077121437.