Engine damage - faulty conrod, Nasty ****
 

Hi guys,

This is how I started my season.

Went for a weekend with Porsche Club Norway (PCN) to Gotlandring in Sweden (Gotland).
76 Porsches met up in Oslo, and drove there un Thursday. The entire track was booked Friday and Saturday.

We had a nice trip crossing Sweden.

When in line waiting for the ferry, we got a reality check of the ongoing war in Ukraine.
A lot of swedish soldiers and tanks was onboard the ferry.

Friday was a track day, with a walk through around the new track.
Friday we had half the day on the northern track, and rest of day on the Southern track

My 930 responded very well, and the new Toyo R888R had very good grip.

I got to push the car better and better in the turns. Found the spot where I could push more speed out of corners.

Saturday, we woke up to some rain, so I took good time before going up to the track.
Rain had stopped, and peaople started to go on the track.

There was some guys from PCN that wanted to ride along with me and a friend, also driving a classic Porsche, a carrera 3.2.

We installed go pro and set of.
Driving was calm and easy, due to the wet track.

However, right before end of track, at 4500 rpm, boost arond 0.7, engine suddenly made a bad noise and froze up.

I had no sound in the engine of any indication of anything wrong.

When looking under the engine, I could the the entire bottom of the case was gone. Oil pump was partly out.

My thought here was a bruken rod that had hit on top of the oil pump and pushed it out. (Now after inspection, this is what I think happened)

Let's start with the fun parts first :-)

Here is a video of some of the first laps on Friday (the fun day)

https://www.youtube.com/watch?v=290ra8tRefc

So back to where is got bad.

Here is a in-car video when the rod snapped.

https://photos.google.com/share/AF1QipPV6HsbIIwRUbOXL2zfJx97zrFjkH0dKfx7colz71Ccys MaVLA4Mh4fAicAtLH4tA/photo/AF1QipMaMhuGfVcOPeea3nM4XytcApuNRhPCR13sBhh1?key=a UNHd3Fxd3B2MEtsd3ZZLVRiODJPcFY4M1doWHl3

This is what is looked like at first inspection.

http://forums.pelicanparts.com/uploa...1652092159.jpg


Luckily, PCN had an empty trailer, so me and my car got to hitch all the way home.

http://forums.pelicanparts.com/uploa...1652092298.jpg

And then to the nasty engine damage.....
I have seen some connecting rod failures, but never seen som much damage like on this engine.

Looks to me like fatigue fracture failure on the con rod for cyl#2.
As you can see quite a clean brake surface on part of the rod.

http://forums.pelicanparts.com/uploa...1652092847.jpg
http://forums.pelicanparts.com/uploa...1652092847.jpg


The rod has then whipped around inside the engine and hit on top og the oil pump, pressing it out of the case, and made an extreme damage to the case

http://forums.pelicanparts.com/uploa...1652092953.jpg


Rod has then whipped around more before if got stuck between cyl # 5&6


http://forums.pelicanparts.com/uploa...1652093096.jpg

http://forums.pelicanparts.com/uploa...1652093211.jpg

The impact of the rod between the 2 cylinders has been so hard that there has been thermal melting of the aluminum between the 2 sylinders.

I used a saw to free them from each other

http://forums.pelicanparts.com/uploa...1652093320.jpg


As you can see on photo above, bottom of cylinder sleeve is bent.


Luckily top ends are fine.

But it is going to be costly, just in parts :-(

Need to buy:

engine case
camshaft
oil pump
rods
rod bolts (ARP)
2 new cylinders & 3 new pistons (JB Racing cylinders, JE Pistons)

FYI

Standard 3.3 rods, ARP bolts, about 505whp at 1 bar boost

Holy ouch dude. Glad you were in a fairly safe place when it happened.
Sorry to see how catastrophic it was, yikes!
Best of luck with the rebuild~
J

Sorry to hear this. I've been through two rod failures on my Audi S4 and that time after the failure when coasting is so intence in your head trying to figure out what happened and how to get back home. BTW: Fix the camshaft to crankshaft on your list : )

Good luck to be able to use the empty trailer and good planning of PCN. I once had electrical problems with my 930 on the ring but I got my car there and back in a multicar hauler so it was not a problem.

Wow..that is some carnage and going to be expensive.

How many miles are on this engine? To let go so catastrophically at 0.7bar and 4500rpm is not close to full engine load..so odd.

I am sorry this happened and wish you the best in the rebuild. What's the plan to source a case? Please keep us posted on your progress.

I have a complete 1979 3.3 engine that I will use the case and oil pump from. Butu the plan was to build that case to an original stock 3,3

But prices just for a case is so sick now. So will use this case to keep the cost down.

I have sorted a 964 crankshaft (have 964 crank in my current setup)

Will buy new ARP bolts, and maybe go for carillo rods or some similar

Dang, sorry to see that. I just read an article about material fatigue in connecting rods, ended up buying some Carrillos for my next build afterwards..

wow.

my brother has an AWESOME set of tools.
(fast times at Ridgemont high)

totle, My heart goes out to you with this failure, really sad. I like to know what ecu are you running? I ran 620rhwp with stock rods with ARP bolts and never had any issues, this failure is big and strong to break the case like this, looking at the pictures if the rod is still attached to the crankshaft as per the picture of the upper rod part attached to the piston, I believe that the rod may have been elongated and finally separated, one way to check is to check all others to see if you see something that can confirm this theory.

the 964 crankshafts you can find pretty much everywhere and if needed send to Marine Crankshaft they will fix whatever and bring the crank to OEM specs in case you find a used one that needs minor repairs.

Thanks.

I am running LinkECU, an older version, G3
But as you can see from AFR, still running rich. Down at 10.x at boost

Rodbolts gave up in the end, as the rod was stuck in the case

Perhaps surface crack propagation.

Oh man, I’m sorry. Those pix are sickening. All th best going forward.

I'm sorry for your misfortune :(

Do you not think the melting could have come first, and the case distortion caused the rod to break?

Sent from my SM-G988B using Tapatalk

No I don’t think so.
Melting is due to brute force, not engine heat

Sorry for your loss. OMG, that is horrible. http://forums.pelicanparts.com/suppo...ys/a_pukey.gif

That sucks, Trond.
“There but for the grace of God go I.” With 3 kids in college that would sideline me indefinitely.

Thanks. A big setback