Go Back  AudiWorld Forums > Technical Discussion > Engines > 4.2 V8 Discussion
Reload this Page >

07 A6 FSI Engine Oil Cooler O-Ring Replacment

07 A6 FSI Engine Oil Cooler O-Ring Replacment

 
Old 12-24-2018, 08:36 PM
  #1  
AudiWorld Member
Thread Starter
 
Join Date: Jul 2014
Location: Chicago Suburbs
Posts: 59
Likes: 0
Received 0 Likes on 0 Posts
Default 07 A6 FSI Engine Oil Cooler O-Ring Replacment

I posted this in the A6 C6 section under alternator removal since I was looking on how to remove the alternator to get at the oil cooler o-rings. I thought that I would post it here under a more appropriate title.

[color=left=#222222]First I removed the belt tensioner to access the two bolts holding the alternator on.[/color]
[color=left=#222222]Then I removed the 5 bolts holding the alternator bracket. Now I have access to the 4 bolts to the engine oil cooler.[/color]
[color=left=#222222]Once removed I replaced the engine oil cooler O-rings which were very brittle and compressed.[/color]
[color=left=#222222]The above steps do not mention disconnecting the power, all the hoses, wires and obstructions which made this a difficult and time consuming job.[/color]

[color=left=#222222]I was able to replace the engine oil cooler O-rings from under the car (on jack stands). It would have been a little bit easier to access some of the hose clamps if I removed the passenger side engine mount, but I managed with the engine mount in place.[/color]

[color=left=#222222]Prior to this job I was getting oil in the coolant but no coolant in the oil. When I removed the engine oil cooler I backed flushed it and a fair amount of crud came out. I verified that the engine oil cooler was not leaking internally.

I was also not getting much heat so I backed flushed the heater core with not much success. I did about 8 flushes of the engine with water to get rid of the oil residue before filling with coolant. With no success of getting hot air out of the passenger side, I added a tablespoon of PBW (powered brewery wash) used in the brewing industry to clean brewing equipment to the flush water. PBW is an environmentally friendly alkali cleaner safe for use on metals, rubber and plastic parts (I'm a homebrewer). When I used the PBW I started getting really hot air from the heater. I did one final flush with water before filling with coolant. With the crud from the engine oil cooler and the heater core being dirty, I noticed that the heat is much improved due to increased coolant flow.

Due to saving myself $$ by doing the work myself I was able to justify buying some new tools.
The first tool is a coolant air purge tool: https://www.ecstuning.com/b-schwaben...l/003466sch01/[/color]
The second tool is a hose clamp pliers: https://shop.advanceautoparts.com/p/...e+clamp+pliers
Both tools were a big help.

Overall I rate this job on par with replacing a timing belt (from my Acura) as far as difficulty.

Hopefully my Audi oil & coolant leaks are a thing of the past since I have previously replaced the oil filter o-ring, oil separator, throttle body adapter, PVC hose and valve cover gaskets.

[color=left=#222222]Below are a few pictures:[/color]
[color=left=#222222]1. After removal of oil cooler with original O-rings[/color]
[color=left=#222222]2. oil cooler reinstalled[/color]
[color=left=#222222]3. alternator reinstalled[/color]
[color=left=#222222]4. [/color][color=left=#222222]New O-rings installed[/color]




[color=left=#222222] [/color]
A6 4.2 Vier is offline  
Old 12-25-2018, 07:38 AM
  #2  
AudiWorld Member
Thread Starter
 
Join Date: Jul 2014
Location: Chicago Suburbs
Posts: 59
Likes: 0
Received 0 Likes on 0 Posts
Default

I am not convinced that my oil coolant issues are resolved. I will need to drive the car for a week or two to see if oil is present in the coolant reservoir.

My gut tells me that there may be a hairline fracture in the engine oil cooler that didn't show up when I tested it for leaks with water. The design of this engine oil cooler would not leak oil in the coolant from worn out O-rings since the coolant side is opposite from the oil side.

If the engine oil cooler is bad at least I know the routine to replace it.
A6 4.2 Vier is offline  
Old 01-06-2019, 11:14 AM
  #3  
AudiWorld Member
Thread Starter
 
Join Date: Jul 2014
Location: Chicago Suburbs
Posts: 59
Likes: 0
Received 0 Likes on 0 Posts
Default

Update:

I used a bottle of K-Seal in my coolant which solved my oil in the coolant problem.

After testing/driving the car, I discovered that the heater control valve was faulty (no heat on the passenger side, little heat on the drivers side). I replaced the heater control valve and all is working great again.

Makes me wonder what component/sensor is due to leak next.
A6 4.2 Vier is offline  
Old 06-18-2019, 04:17 PM
  #4  
AudiWorld Junior Member
 
Join Date: Apr 2018
Posts: 15
Likes: 0
Received 0 Likes on 0 Posts
Default

Thanks ...considerably....great approach to getting at everything without ripping out half the engine compartment...especially the removal of the alternator bracket. I'm def going that route.
Jim Castronova is offline  
Old 06-19-2019, 03:36 AM
  #5  
AudiWorld Member
Thread Starter
 
Join Date: Jul 2014
Location: Chicago Suburbs
Posts: 59
Likes: 0
Received 0 Likes on 0 Posts
Default

Originally Posted by Jim Castronova View Post
Thanks ...considerably....great approach to getting at everything without ripping out half the engine compartment...especially the removal of the alternator bracket. I'm def going that route.
Glad that I could help.

Update, I replaced the (4) variable timing o-rings as they started leaking badly at 140K miles. The ones near the valve covers make it appear that the valve cover gasket is leaking.
A6 4.2 Vier is offline  
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Letsgopens
A8 / S8 (D3 Platform) Discussion
10
01-29-2019 04:20 PM
A6 4.2 Vier
A6 / S6 (C6 Platform) Discussion
2
12-25-2018 07:44 AM
fritzfedor
A6 / S6 (C6 Platform) Discussion
0
10-23-2014 10:14 AM
KL'00-2.7T
A6 / S6 (C5 Platform) Discussion
1
02-07-2001 03:16 PM


Thread Tools
Search this Thread
Quick Reply: 07 A6 FSI Engine Oil Cooler O-Ring Replacment


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: