Coolant leak, '01 A6 4.2

[john at westcoastgarage.net]

On 4/22/2010 5:44 PM, Grant Lenahan wrote:
> Ohhhh! Good catch!
>
> Apparently time consuming to get to
>
> Grant
> On Apr 22, 2010, at 8:07 PM, kneale at coslink.net wrote:
>
>    
>> There's a guy goes by the name Fusilar or something like that on Audiworld
>> and Quattroworld who has made an aluminum replacement for a plastic pipe
>> Audi installed in the coolant supply between the block and the oil cooler
>> on the passenger side of 4.2 V8s.  His pipe features double Orings on each
>> end.  Audi's plastic has a single O-ring on each end.  The pipe is about
>> 2.5-3 inches long.  Failure of the plastic at mileages upward of 100k is
>> being reported.  I have one of his pipes in the glovebox of our S8.
>>
>> Original Message:
>> -----------------
>> From: john at westcoastgarage.net john at westcoastgarage.net
>> Date: Thu, 22 Apr 2010 16:52:35 -0700
>> To: quattro at audifans.com
>> Subject: Coolant leak, '01 A6 4.2
>>
>>
>> Anybody here with any experience on these "new" cars?  We have a car in
>> the shop with a pretty respectable coolant leak on the right side of the
>> engine, and we're looking for some BTDTs.
>>
>> Thanks, John
>>      
>
>
>
>    
A report from the trenches.  Just so you all know, the leak was indeed 
the pipe from the block to the oil cooler.  I bought the aluminum double 
sealed version from the guy mentioned in the replies and installed it.  
BTW, the dealer supplied 50+ buck "complete" reseal kit isn't.  You have 
to buy the pipe and the 3 seals for it and the external pipe 
separately.  Not needing the pipe ans its seals left me needing only one.

While simple, the job is time consuming.  It can all be done from the 
bottom, once the expansion tank cap is removed, the battery 
disconnected, and an 8mm (13mm wrench size) removed from the top on the 
oil cooler (it's visible, and removable with a 1/4" swivel socket).  
Removing the air pump first makes for plenty of room to both access and 
to R&R the alternator  and the oil cooler housing.  Once you can see the 
drain on the oil cooler housing (some have an extension, some don't), 
drain the left side of the block, then the right.  It appears that 8 
hours is the usual first timer labor, but it's easier than a 944 and I 
was able to do it in somewhat less time.  It's difficult to clean out 
the debris from the bore in the block, and care must be taken to avoid 
gouging the aluminum.  You have to remove the front sway bar brackets, 
the small L shaped subframe, the alternator, the oil pressure switch, 
the external coolant pipe and its bracket aft on the engine, the oil 
filter, the wiring harnesses in that area, and a little motor mount 
looking thing which is attached to the oil cooler housing.  From there, 
the only difficulty is removing 3 shallow Allen head 10mm bolts that you 
cannot see.  Various combinations of both 1/4" and 3/8" extensions and 
8mm Allen sockets did the trick.

Thanks for the tips, BTW, and I hope this helps someone.  I realize I 
can never have a 4.2 A6Q, because I should NEVER again be put in a 
situation where I can have too much fun ...................

John