So driving around I heard a rhythmic/rotational sound that was very faint but unfortunately load/rpm dependent and not road speed. All gauges looked fine at higher RPM, so carry on... A few minutes later, noticed slightly lower oil pressure, but no light. Well, after about 5 minutes the light was practically on solid, and noise was louder. Flatbed to the shop, pull oil filter, and, well that’s how it all started. Filter was full of orange and silver metal flakes. I was hoping for a valve guide or something, but realized this was wishful thinking. After a few preliminary checks, realized there wasn’t any skirting this issue, and decided to pull the engine.

I was extremely lucky to be managing a repair shop at the time and we had an available bay in a detached building. The owner was nice enough to let me use it for just shy of 3 months. Why was it in there so long? Well, I’d rebuilt/swapped engines and whatnot but never a flat motor and certainly not a Porsche flat 6. Add to that, there were about 3 dozen special tools that the 150+ pages of engine manuals referred to as being essential. It would’ve added up to a substantial investment just to acquire the tools, which I wasn’t going to do. With a project like this, I either want to go all in, make do with what I can put together, or buy a new or used engine and sell the old one for parts.

Anyway, out comes the engine:


I did not have an engine hoist, or even an engine stand. I realized how nice that would’ve been later... Anyway, instead, I simply lowered the the car on a workbench (that we attached wheels to), then unbolted the mounts for engine/trans, using woodblocks to level the assembly, disconnected everything and simply moved the car up away from the engine/trans assembly.



And finally completely away from the car;

I choose to remove the A/C compressor first so I didn’t have to recharge the system or evacuate beforehand. I understand a lot of people disconnect the lines first instead. Easier, but ultimately more work IMO.



Cylinderheads and most accessories removed:


Continuing to strip it down:


Cylinder drive assembly. This is interesting in that it’s very unusual to have a “bearing housing” for the crankshaft for a modern car. This is the modular Porsche design, which is unlike the 996 turbo which shares many parts with the LeMans winning GT1, as well as all the way back to a 959. Anyway, in this particular design the bearings are housed in an aluminum composite, bearing beds however are a harder metal.



Cleaning everything up and installing new rod bearings:


I later found out about the assembly “issues”. I need to upload more pictures but one has to join one block of rods to the pistons and assemble the rod caps inside the engine block once the cases are joined, and the other bank has to have the rods assembled and joined to the pistons inside the cylinder case. This point required several alignment and assembly tools to line up the rods, assemble wrist pins (!), install wrist pin clips (!!) while going THROUGH the side of the block from a tiny opening (!!!). No amount of planning or suspending the engine was going to let me do this, so I had to design and build a tool. Thankfully some copper pipe from the hardware store, a hose clamp and careful notching let me install the wrist pins, and I would use a smaller pipe from inside the outer one holding the wrist pin clip to remove the clip. Here’s that masterpiece:



Oil galleries cleaned and new gaskets for the pick up strainer, air oil separators, etc.



First road trip to Ohio after the rebuild to visit my now ex girlfriend. This spot is not only 800+ miles from home but it’s about 25 miles on unpaved roads. I must’ve driven back into town at least 6 times in the 3 days I was there. The experience of pushing this thing sideways through all that muck at stupid speeds made it all worthwhile.



Will post more later!

8/13/2014 6:14:51 PM

Nice thread Ahmet! However, a question:

Quote :

"Flatbed to the shop, pull oil filter, and, well that’s how it all started. Filter was full of orange and silver metal flakes. I was hoping for a valve guide or something, but realized this was wishful thinking."

You never stated what the point of engine failure was. So what was it?

8/14/2014 8:34:41 AM

From the GT2 vs 360 thread;

Quote :

"I’ll tell you this though, I had a catastrophic engine failure (spun rod bearing) in a 911 two years ago. "

I’ll update again when I get a minute to sit down.

8/14/2014 10:48:19 AM

Ah thanks! And sorry I did read that...in one ear, out the other. What was the engine mileage when that happened? 140k or so?

8/14/2014 12:41:35 PM

I cant even fathom a situation where a valve guide would fill a filter with metal. The two dont exactly live together......

Did you blow the rod bearing(s?) out due to too much ignition timing / preignition?

Nice work on the improvised tool. How did you get the rods/pistons out before you realized it would be tough to get them back in? just split the housings and yanked the sucker into two halves :-D ?


A+ would look at photos again

8/14/2014 7:50:32 PM

they put a subaru engine in your porsche? i knew it!

8/14/2014 9:46:28 PM

holy hell

8/15/2014 12:36:52 AM

Bearing damage was around 167k if I remember correctly.

I knew the metal particles in the oil (or low oil pressure for that matter) couldn’t possibly be caused by something like a valve guide, but I was grasping. The filter was absolutely filthy;


Having driven BMWs with rod bearing damage, I was surprised at how quickly it went from barely noticeable to bad :/ I was a little disappointed, then again it was high in age and didn’t live a kind life. The engine looked fine inside otherwise, but still. I’d like to think that any well engineered engine cam make it to 170k miles and beyond with basic maintenance.

Bearing housings BTW-baonest, that’s pretty funny. I’m pretty sure this bearing assembly business is unique to Porsche though, the bearing beds being made of a separate metal and cast into the aluminum cylinder halves. The webbing is more obvious at the top of the picture:


Speaking of case halves (cylinder block half? lol):


It was a stressful project to dive in for sure, but I’d been doing engine swaps both for work and on personal cars for some time already. Here’s a 20k mile 996 C4S getting an even newer and updated engine:

New Porsche engine cha-ching$$$:




While we’re at it, some random projects. One of the first 996 turbos I started modifying (belonged to a good friend):

You can see the exposed turbo at the bottom left of the picture.

What a fantastic design, so little piping. Exhaust is a 3 into 1 going straight to the exhaust turbine and the compressed intake goes into the intercoolers mounted mere inches away. The side scoop intakes are placed in a high pressure area (at the bulge of the rear fender) and after being pushed through the intercoolers, exist straight through the bumper at a low pressure area. Studying the aerodynamics of this very thing was one of the reasons I decided to buy one of these things. Very little drag and huge airflow to support sustained max boost runs at 150+mph for a tankful at a time (!) Check out the normally hidden ducting:


One of my favorite cars, an original Westfalia:


Alas, if everyday there was working on these things on my own, I’d probably still be doing this stuff. Ah, nostalgia...

8/15/2014 12:50:53 AM

Here’s the access hole used to assemble one block of pistons and wrist pins/retainers, etc.



Here’s a close up:


Note that you’re looking THROUGH the hollow wrist pin and can see all the way through cylinders 4 (that the piston is in), access hole through cylinder 5, and the first access hole of cylinder 6 and the shiny reflection is the combustion chamber wall of cylinder 6(!)

Here’s assembling piston 6:

In this shot, there are no con rods in the way so you can clearly see through to the side of the piston though note the crazy fact that you’re still looking THROUGH the side of the combustion chamber walls, which have an access hole machined in.

8/22/2014 6:15:36 PM

Fascinating! I had no idea you would have to assemble an engine that way. Looks like some limited access for sure. Thanks for sharing.

8/22/2014 8:57:59 PM

My pleasure, I'm glad you found it interesting! It was one of those experiences that I didn't particularly enjoy going through, but am glad I went through it looking back! I suspect my e30 pipe dream may be a similar situation...

8/25/2014 11:18:32 PM

I want an e30, but waiting a little while myself

8/25/2014 11:26:49 PM