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Posted by: mskala Jun 23 2018, 09:26 AM

Well, I started to get a new decent size oil leak onto the left header.

Traced to crack in round edge of oil cooler, not the welds. This is the cooler from
NLA Parts which is less than 3 years old. This is a stock photo, mine is not out of
the car yet. Anybody had problems in this area?

Posted by: sithot Jun 23 2018, 09:55 AM

I’d wager the stamping of that part created a stress crack.
Who is making these? BEHR?

Posted by: bdstone914 Jun 23 2018, 11:38 AM

Contact Stoddard.

Posted by: mskala Jun 23 2018, 02:32 PM

I don't know who's making these. I've seen a new replica 911 cooler which
doesn't look the same.

Posted by: sithot Jun 24 2018, 04:36 AM

Everyone is using the same supplier. Patrick, Stoddard etc.

This is a good place to use if you ever find an original or you want the one you have tested and repaired. Aviation industry frowns heavily on leaks.

http://www.oilcoolers.com

Posted by: Mark Henry Jun 24 2018, 10:04 AM

I agree it doesn't look like an OE cooler.
I was wondering where these are made (china?) but the site says germany.

Not a cheap price cooler, I also agree on contacting Stoddard's, if leaking from where you say it's a definite manufacturing defect.

Posted by: porschetub Jun 24 2018, 02:48 PM

I have found Stoddards good to deal with but not sure if they would step up after 3yrs ..who knows,don't think it has been the victim of excess oil pressure as the core would have blown first,I had a stock cooler pop @ the core under normal use but it was 30+yrs old.
As mentioned it is most likely stressed @ that area,no point in just welding up the crack,thinking a run of weld all the way along would be the best solution if done by the right person ,good job for Ben .

Posted by: mb911 Jun 24 2018, 03:21 PM

But Stoddard will most likely stand behind it..

Posted by: mskala Jun 24 2018, 04:55 PM

Thanks all. Probably engine will be out ina couple days then I can get a pic.
Right now there's almost no room to even get a mirror on a stick in there to see.

Posted by: pete000 Jun 24 2018, 05:20 PM

I think these reproduction coolers are made in China. I was on the fence getting one but sourced a good BHER OEM cooler and had it cleaned and tested. I still have my orig cooler but it has a pin hole leak. I will contact the oil cooler link to see if it can be repaired. Would be nice to have a spare.

There are a few on eBay at various prices and conditions. Patrick Motorsports does a BHER 911 cooler conversion mod using a different oil line with AN 16 fitting welded on. This is what my six is currently running.

I plan on dropping the engine soon to replace it with the correct six cooler and line soon.

Posted by: Krieger Jun 24 2018, 06:23 PM

About 18 months ago I was looking at the ones Sierra Madre was selling. I asked the guy where it was made. He told me it was OEM from Porsche. I cannot remember the price. Maybe $1600. I figured I see if I could get it from Sonnnen online. This is my local dealer in Marin. I was able to order it and pick it up from them. It was $900! I wasn't sure what was going to show up when I got it but damn it came in a box with a Porsche part number! Looks almost exactly like the original, but a funky green color paint.

Posted by: sithot Jun 25 2018, 05:24 AM

Chinese manufacturers can do the work but it's up to the "contractor" to follow through on Q.C.. There are a lot of parts including some very nice wheels and brakes that are produced in China. The key is to stay on top of the manufacturer until he or she "gets it right". About 10 years ago I had this discussion with a known Porsche specialty parts vendor. He was adamant about this fact having gone through several (GOK) iterations of a part they were making. When it was right, it was RIGHT and as good as anything from Germany or elsewhere.

Good luck!

Tom

Posted by: bdstone914 Jun 25 2018, 08:53 AM

I suspect an design flaw. An oil cooler continually expands. The radius is going to be an area where the stress contentrates as the top flat plate flexes.
I would contact Stoddard an enquire as to there design and development.
What is the burst pressure and safe working pressure tests ?
Were they subject to a burst test?
I worked for Hayden Oil coolers for 28 years as a Product Development Manager.
We had a dumb ass company President who wanted oil coolers that looked different so he ordered them to be build with square copper headers. They all bulged at normal operating pressure, deformed and failed it ran long enough. They had 90 degree corners. Worst then this.
This is my opinion as a possible cause. The cooler should be subjected to engineering failure analysis.

What say you other engineering types ?

Posted by: mskala Jun 25 2018, 08:47 PM

Bruce, I'm not that kind of engineer but that seems right to me.

Update, engine is out, cooler is not off yet but got a picture of crack.

Posted by: porschetub Jun 25 2018, 11:09 PM

No need to drop the engine to change,nevermind the changeover is a PITA in situ,I think that part has cracked because it has been formed wrong,appears the alloy has stretched on the outside of the radius,the BEHR cooler has a weld all the way along that edge and looking @ my old one it looks like it 2 pieces ,interesting as yours appears to not be a true copy: D .
Good luck sorting it.

Posted by: mb911 Jun 26 2018, 06:28 AM

I think the metal was formed with the grain rather then against the grain with aluminum thats a huge issue depending in alloy

Posted by: Mark Henry Jun 26 2018, 08:09 AM

Power of the internet, I would contact them and link to this thread.
They may have a hard time selling the coolers if they don't come good on this. If they don't I'd consider cross posting on a couple other forums.

That would be hard to weld, first there's contamination issue and then the weld ending may just create a new stress point for a future crack.

Posted by: bdstone914 Jun 26 2018, 08:38 PM

Call them. They should be concerned. Possible huge liability. It will probably take metallurgical analysis. You need to get to the right person at Stoddard. I know some of the folks there. Good company

Posted by: bdstone914 Jun 26 2018, 10:42 PM

Original Behr cooler. Note the design difference


Attached thumbnail(s)

Posted by: Per Schroeder Jun 27 2018, 07:44 AM

I agree. Please give us a call to discuss (this is *always* the best answer when dealing with a company like ours)

FWIW: We offer a 12 month warranty on all of our parts--like the Factory itself. That said, we will make every effort to make it right.

Please call and talk to our sales manager, Pete Yanda (800) 342-1414

Per Schroeder
Stoddard NLA