[V8] Well, it's spring....

Scott Simmons indischrot at gmail.com
Sat Apr 19 18:44:32 PDT 2008

PT is Alusil, ABH is Nikasil?  I thought only the Bavarians used Nikasil.

~Scott S.

Bastian Homburg wrote:

>um....let me explain:
>The ABH (4.2) and  PT (3.6) motor were assembled using different 
>technology:  With the small motor, they used some kind of etching 
>process whereas the 4.2 used nikasil coated cylinder walls. And exactly 
>this coating is washed off over time due to a chemical reaction with 
>sulphur components found in gasoline. That is why most of the ABHs use 
>lots of oil even when the rings are perfectly OK. This is worse in 
>manual trans models, which are geared shorter and tend(ed) to be driven 
>more aggressively.
>And only the very last V8s had R134a AC from the factory. All '92s as 
>well as most of the '93s still were equipped with R12 - the switch to 
>R134a was made around May 1993.
>Retrofitting the system (no matter if 'old' or 'new' control unit) to 
>R134a is pretty easy. Audi sells a "retrofit kit" that includes 
>everything you'd need
>(part no. 4A0298107A for the denso compressors in the 3.6 and 4A0298107 
>for the Zexel compressors in the 4.2), plus there's even an official 
>retrofit guide (see 
>http://www.audiv8.com/forum/download.php?Number=92939 for a pdf 
>version). Cost for this kit in Germany is 200 Euros.
>The refrigerant type should definitely not be a major point in deciding 
>for or against a specific V8.
>Dave Saad wrote:
>>On the oil consumption issue, I think a lot of 3.6L motors had the  
>>same problem.  Mine sure did.  It seems that the problem is the  
>>design of the oil ring - it is just bad.  I put new rings in mine and  
>>oil consumption has gone down to a normal level.  My plugs now are a  
>>nice brown too instead of crusted black.  I am not sure why some  
>>motors seem OK while others are oil burners from the same model  
>>years.  maybe the factory used two different styles of ring during  
>>On the other issues, the AC is probably the biggest to me.  Having  
>>the R134a would be nice just for the ease of servicing. The newer  
>>control head would also be nice I suppose, but the old style works  
>>well enough.
>Audifans V8 mailing list
>Send posts to: mailto:V8 at audifans.com
>Manage your list connection: http://www.audifans.com/mailman/listinfo/v8
>You can help keep the audifans site running by shopping at http://audifans.com/shop/

More information about the V8 mailing list