Coolant leak, '01 A6 4.2

[Kneale Brownson]

Thanks for the follow-up writeup, John.  Every other approach I've read 
about has been from above with the timing belt removed.  Glad you could 
get the metal pipe instead of relying on Audi's plastic junk.


john at westcoastgarage.net wrote:
>
>> 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
>
>
>