996 Oil Cooler Leak

[2001996Tip]

My 2001 996 Base Tiptronic Cabriolet has an oil leak from the oil cooler/heat exchanger 996 107 025 57.

Can I replace the part without lowering the engine?

Will the catalytic converter have a risk of damage if the engine is lowered?

Look forward to your experience and advice.
 

[DBJoe996]

I saw that you posted on Rennlist as well, and never got a response.  The oil cooler is located way back on the right side of the engine.  Replacing the four O-rings (2 for coolant and 2 for oil, and they are different sizes) under the oil cooler requires removal of the A/C compressor, then removal of the intake on Bank 2.  You have to perform the same steps for installing and replacing the  oil cooler entirely.  Read up carefully on removing the A/C compressor because it can be difficult getting the bolt out behind the compressor.  You need to remove the intake because you need a straight on shot up and down for removing/replacing the oil cooler.  You will also need to drain some coolant so the level in the engine is below the oil cooler, otherwise you will contaminate your oil.  And yes, you will need to support the engine with  a jack, remove the engine mount nuts and lower the engine to the cross-member (as low as it can go still in the car) in order to gain enough room to remove the Bank 2 intake.  The intake bolts can be difficult to gain enough access to remove.  I have found it necessary to remove the rear bumper and heat shields to lower the engine as far as you can get it, without removing the mufflers/cats.  Since the mufflers/cats are attached to the engine, it all comes down as one unit.  You also will have to undo the connections for the O2 sensors so you don't strain the wiring lowering the engine.

 

If you are going to tackle this job yourself, I highly recommend getting a Bentleys Service Manual for the 996. They are available on Amazon.

You can see the location of the oil cooler in this picture taken from the transmission side of the engine.  It is the silver looking "box" under the Bank 2 intake.

 

 

Also, if the oil cooler requires replacement, only get one from a reputable source, i.e., OE Porsche.  Some people have replaced the oil cooler with a cheap knockoff brand and found that they leak because the flat surface of the oil cooler is not flat and smooth like it should be.  Given the work involved, this is no time to try and save money and have to do a do-over.  I would replace the oil cooler and all O-rings at one time.  You will need new intake O-rings as well, as well as a bunch of other items (such as Porsche coolant for a refill when done).  Parts Source - http://www.autoatlanta.com/porsche-parts/hardparts.php?dir=996-99-05&section=104-00

Edited November 24, 2017 by DBJoe996

[2001996Tip]

Thank you for your detail explanation.  My shop lowered the engine and replaced the oil cooler.  The check engine light was on with a error code for catalytic converter bank 2.  Could this related to lower the engine or removal of the intake on Bank 2?

[Ahsai]

If it's P0430, it's unlikely to be related to lowering the engine. It could be related to battery disconnect though, which triggered the catalytic tests to be re-run and that cat is marginal.

[2001996Tip]

What is my best option (money-wise) if the light comes on again?

[JFP in PA]

5 minutes ago, 2001996Tip said:

What is my best option (money-wise) if the light comes on again?

 

Used cats out of a wreck.

[Ahsai]

A used one could be a good option. There are CA approved after market cats for $500 each but I couldn't find any for New York (assuming you're in New York as shown in your sig).

[2001996Tip]

Yes.  I am.  

[Ahsai]

Search for "porsche 996 down pipe" on ebay

[Andreas Efstathiou]

My 996 C2 build in 1999 has oil cooler issues for the last 3 years. The engine was completely rebuild by Porsche Germany 3 years ago.

 

Have replaced the oil cooler in a Porsche approved workshop in Cyprus, two times already and last week it failed again.

 

As i believe this is a common issue on the M94-95 engines, can you please recommend an upgrade solution to this problem.

 

You are well aware that for the repairs the engine must be lowered down and is a rather costly exercise overall.

Look forward to your experience and advice.

[Andreas Efstathiou]

Correction on the engine model M96

[JFP in PA]

2 hours ago, Andreas Efstathiou said:

My 996 C2 build in 1999 has oil cooler issues for the last 3 years. The engine was completely rebuild by Porsche Germany 3 years ago.

 

Have replaced the oil cooler in a Porsche approved workshop in Cyprus, two times already and last week it failed again.

 

As i believe this is a common issue on the M94-95 engines, can you please recommend an upgrade solution to this problem.

 

You are well aware that for the repairs the engine must be lowered down and is a rather costly exercise overall.

Look forward to your experience and advice.

 

I find your comment that oil cooler leaks are common rather odd as we have only seen perhaps six leak over decades of working on hundreds of these cars, and most of those leaks were on Boxsters.

 

What kind of leakage are you experiencing?  Coolant or oil? Intermix?