oil leak dilemma part 2 (damn!)
 

Hi!
Not so good news.

Not long ago I reportet my work done about the "triangle of death" alias "the oily trinity".

As the weather was about OK on sunday, I took it for a spin around town, also to do the check up on my resetted oil cooler upgrade.

Just about home, stopping at a traffic light, I noticed that well known and feared smell of freshly burnt oil evaporation on the hot engine block and heat exchangers.

Comming home I parked the car directly backwards into the garage to my working position and looked under it:
- very obvious drip at engine case just below cyl.6
- oil dripped on heat exchanger that found its way from below cyl.6

I instantly thaught that I'd done something wrong in my previous work (trinity).

So I jacked the car up, jacked the engine, loosened the engine mounts, dropped the engine 5cm, took of the aircover, and sneek-peeked with light and mirror behind the intake. trinity looks shiny and fresh, everything tight, dry and in place.
good, but damn nontheless!

I guess that leaves me with the engine oil cooler seal rings to bother about(?).

"why on earth didn't he change these seals a week ago, when he had everything accessible?!" you might say.
Well, thats what I'm reproaching myslef now too.
The focus on the trinity as the culprit for previous oil spill distracted me.

Just ordered the seals and I'll work on that as of this evening.

The weird thing is, I didn't have this oil leak-/drip pattern before.
Maybe it's because I cleaned everything up, the oil leaking now flows better?

It's so anoying... :-(

triangle
 

I personally dont believe that the seals on the cooler can fail, 15mm seal into a 10mm squeeze..and I havent seen it myself if it does exist.
A 3.2 to 3.4 build with cam oil line restrictors.
Great pressure but then all is new.
Oil leak dripping on the heat box exhaust right side just before the connect for the cross over.
Now, I ve had thermostat seals new fail because theyre not sealing so I add a coat of 574 above the seal.
Always install an idiot light switch with new.
Opened the triangle and resealed again
Still leaking, sprayed everything down and was getting drops off the front lower stud on the cooler.
Triangle chainged so its time to pull the cooler and add new seals and pressure test. Previously change the idiot light out and it drops on to the trailing arm. As Im installing the cooler, I knock off the switch on the trailing arm and behold....
Bruce

http://forums.pelicanparts.com/uploa...1392045423.jpg

I think I see your problem! ;)

Bruce: but when I have no oil around the trinity, it must be something else?!

Picked up these just now:
http://www.imgbox.de/users/public/images/9PIiIHKkOw.JPG

http://www.imgbox.de/users/public/images/JGLBOb3ZYr.JPG

Once you get the oil cooler off have it pressure tested. Mine had sprung a leak.

get the engine out, so much easier
greets

so I semi-dropped the engine again and drained the oil (disconnected the oil cooler hose).

took the intake unit off...
http://www.imgbox.de/users/public/images/Iktfw5I09c.jpg

to clear access to the air flow cover... (no more oil from the trinity-area)
http://www.imgbox.de/users/public/images/KGPRxpJkof.jpg

then I took off the right engine tin, unscrewed the 4 nuts (2 at top, 2 at bottom) and pulled it off...
http://www.imgbox.de/users/public/images/WHVGLCDVHQ.jpg

http://www.imgbox.de/users/public/images/bOrua0CQT5.jpg

http://www.imgbox.de/users/public/images/Bp8vkqwOK7.jpg

top...
http://www.imgbox.de/users/public/images/7AKDyFxkSO.jpg

bottom...
http://www.imgbox.de/users/public/images/hio89Q54O8.jpg

now the interesting part:
for me, at least one seal at top has failed, because you can see, that the oil spill has been sitting there for a long time already above the bottom flange...
http://www.imgbox.de/users/public/images/KuNBIqny6g.jpg

http://www.imgbox.de/users/public/images/0yNm9wxQzY.jpg

and here are the seals (green= new)
http://www.imgbox.de/users/public/images/LmaopJqJcZ.jpg

what do you say?...

Looks as though you found the problem.

Yep. Good job.

I'd still pressure test it.....to be sure.

So would I, but does anybody have any suggestions as to what pressure to test the cooler?

cooler
 

I test them at 65 to 70 # because that can be operating pressures
My Stomski pressure tester is the nuts for the job.
Bruce

http://forums.pelicanparts.com/uploa...1392151386.jpg

I made a tester like Bruce's but with just the schrader valve. Use a tire gauge to get it up to 60 psi. If it holds pressure over night you're good to go or put it in a bucket of water.

Clean up the sludge on the case there. At about 7 o'clock in the space behind the cooler is a thin portion of the case that is known to leak. The repair is cleaning thoroughly and applying epoxy. It's a slight indent... you'll see it.

Lapkritis is correct, there is a known weak/thin spot in the casting on some cases. There is a Tech Bullitin from Porsche on this problem. Here is a link to a person who was having your exact problem, has the pertinent info for you(also has some links to other threads). I would hate to see you reinstall with
new seals and still have the problem. Good luck!

http://forums.pelicanparts.com/porsche-911-technical-forum/694440-oil-leak-oil-cooler-leaks-right-lower-side-away-gasket.html

here's the Tech Bulletin on the problem and another link:
http://forums.pelicanparts.com/porsche-911-technical-forum/603362-case-jb-weld-question.html

http://forums.pelicanparts.com/uploa...1392160071.jpg

Subscribed for good tech info. I may need this later.

Good info!
Came just in time ;-)

WHY IS THAT SPOT THERE ANYWAY ?!

Look like the cooler was over torqued deforming the ring, mine did not have that bulge on them when I removed deform. That being said mine start leaking after I changed the 3 rings...

From Post # 8 of http://forums.pelicanparts.com/porsche-911-technical-forum/609149-oil-cooler-seals-leekage-engine-wall.html

http://forums.pelicanparts.com/uploa...1306861983.jpg[/QUOTE]

well, now I start to panic :-(

a)
regarding overtorquing:
I got info that 25Nm is the torque, this was confirmed yesterday at Porsche from the chief mechanic when I piced up the FPM seals.

b) regarding seal types:
I hat seen red, red-brownish ones in the www-search and asked the mechanic about that.
especially that some seals were discribed as thicker giving more torque downforce stability.
he said, that they/porsche has only these green ones from FPM and he had no issues since using them.
he also said that before you really reach 25Nm the flanges will already be tight snug to each other (case to case), so an over-torquing (like a valve cover seal) will not occur as the seal ring ins embedded and cant escape to the sides.

c)
regarding week spot on case behind and left to the cooler:
I ordered the compound as mentioned in the bulletin 999 415 451 40 (EUR 14,-)
does any one of you know as to what Loctite it compares to (if it does)?
I mean those 2K metal-added compunds of the Loctite 34xx series recommended to refurbish cracks, splice & co. on engine cases (e.g. L3463 or L3475).
any idea?