Planet 9

The engine in my 2007 CS failed this past weekend while on track. It lost power, began to vibrate, displayed the CEL and low oil pressure warnings, and began to clank. The engine has 46K miles on it, including 5000+ on the track.

While the engine is not yet completely apart (should happen today) the initial inspection showed connecting rod bearing material in the oil pan. Other parts may have failed as well, but this is what we know for now.

Our path forward is not yet clear. We can install an OEM remanufactured engine, buy a local used engine, our more than likely rebuild the existing engine (if possible) with stronger parts (Carrillo rods, etc).

So, the question for those of you that have been through this with either the M97 or M96 engine is what else fails and should be strengthened during rebuild? We know there is an IMS issue, but what else?

Please do not tell me to remove my track parts, take it to the dealer and lie about what happened. This is not how I work. I raced the car and violated the warranty plain and simple.

List of failures, strengthening needs:

1) Connecting Rods
2) IMS
3)

This is above my paygrade.

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'08 Guards Red CS, 6 sp, 19" Carrera Classic Wheels, Black Standard Leather Interior, Heated Sport Seats, Bose Sound System, Sport Chrono, Auto Climate, Auto Dimming Mirrors, Xenon HID and uh a rocket booster, yeah that's the ticket!

D - Sounds like you spun a bearing(s) on the bottom end... sorry to hear about it. Do you think this was a result of sticky tires and the LVMS oval?

1) Send a PM to K-Man S and see what goodies he put into this motor when they put it back together... he pretty much had the same thing happen.
2) Make sure you use the updated bolts for the IMS problem.
3) Check to make sure crankshaft is exactly centered in the cradle to eliminate RMS problems
4) Think seriously about a 3.4 or 3.8 DFI transplant. Talk to Scott Slauson about it - might cost a little more than a rebuild, but worth it. The new motors have much better oiling.
4) Connecting rods you mentioned

I might add, that I don't think there's much in the way of aftermarket/stronger internals for these motors except for the rods.

brad

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22-year PCA Member
PCA DE Instructor

Brad,

Thank you for the comments. I agree about the rod bearings and will do the things you suggest.

I do not think the failure resulted from any loads seen this weekend, unless I missed a downshift which I do not think I did (no overrev data yet). We were running on a very damp track (fun on R6s!) and I was just taking it relatively easy when it failed.

The silver lining was I had a chance to drive Naybor's BSR for a couple of sessions. You can go flat from infield exit to infield entrance (when the track is dry).

Cheers,

He already PM'd me but I'll repeat it here, I suspect when he gets his engine apart he is going to find that the rod bearing furthest from the front of the motor failed (furthest from the oil supply) at that point the failed bearing will turn to shrapnel and take out the main crank bearing that is downstream from it in the oiling process and leave shrapnel in the pan. Depending on how long the motor was run in this condition it may well be rebuildable and if you rebuild, yes consider using better parts. Some suggestion I would make:

1) stronger/lighter rods - although it typically isn't the rod that fails.
2) stronger lighter pistons - some m97 piston tops have been known to fail, if you are in there already you could eliminate that problem with better pistons
3) You could stroke the motor with a 3.8 crank, wait until you see the price of the crank alone.
4) Make sure your intermediate shaft bolt is the newer stronger design (mine already was)
5) Do something about the oil starvation.

The last one is where suggestions are all over the map they include:

1) Deep sump pan - my V1 deep sump didn't prevent starvation, V2 or V3 that they are on now may be better in that regard.
2) Accusump or similar Italian remote resevoir oiling system - I don't have either, but the Italians swear by their system for their cup cars, many of which had failed rod bearings from oil starvation after their first season in the cup series there.
3) Stronger oil pump - At the time I needed one there wasn't one available, I have heard that there may be now, but I forget who makes it, if you find one let us know.
4) Fix the VOS problem so you don't get oil ingestion that uses up your oil leaving you in a potential starvation mode which is what occurred in my case I believe.

Last, but not least as Beez said, if I had it to do over again I'd put a new DFI motor in instead because it has scavenging pumps in all 4 corners of the heads and a higher output oiling system all around and no more intermediate shaft. You get higher rpm range, less moving parts and better oiling vs. the M97 engine. Once you see the rebuild cost, I think for a few thousand more you could go the DFI route and in my opinion would be well worth it. I'd also like someone else to be the DFI swap guinea pig before me.

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K-Man S

In one of the last couple of Excellence magazines there is a pretty comprehensive article addressing the ongoing support and improvement of our engines in the post-production period. They had a few manufactureres listed who are making "better than OEM" parts and fixes.

I tossed the issue, but if I were you...I would look for the info. maybe someone has the issue lying around.

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2007 Speed Yellow Cayman GT 2.7 (retired)
2008 Guards Red Cayman GT 3.4
"Carpe Cayman"

Excellent (pun intended). I will look for a copy.

Cheers,

Issue #170 or #171...almost positive it was #170.

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2007 Speed Yellow Cayman GT 2.7 (retired)
2008 Guards Red Cayman GT 3.4
"Carpe Cayman"

December 2008 issue of Excellence.
Charles Navarro; LN Engineering
Jake Raby; Flat 6 Innovations
Len Hoffman; Hoffman Automotive Machine
IMS failures
RMS failures
Oil starvation
Cylinder head cracks

Krok, this was during a race or a DE?

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2008 Cayman S, Black, Floormats

Is that the case? Because previously you said that your engine blew because Richard Bennett missed a shift. Which is it?

http://www.planet-9.com/cayman-cha...n-s-now-2.html

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Originally Posted by K-Man S
elmo,
I never said I was mistaken about anything, I said that my understanding of your explanation was different from what I first thought.

Richard did blow a shift shortly before the motor went, and also we ingested oil. Which was the immediate proximate cause I cannot say for sure, could be either, could be neither. No one really knows...

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K-Man S

Timed practice session for a race.

Krok - My guess then, would be a long-term pattern of oil starvation to that rear bearing, or a missed shift... obviously, when you get the DME readout you'll be able to tell if it was the latter. That rear bearing is the most vulnerable, and from what I understand, the hell of it is that when the motor is turned around and used in a 911, the bearing is not as vulnerable due to the difference of the forces on it and the oiling flow when the motor is used in that 911 configuration.

Way cool - that's nearly a minute with the throttle wired-to-the-wood! Sounds like way too much fun to me...

brad

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22-year PCA Member
PCA DE Instructor

[QUOTE=Krokodil;334787]The engine in my 2007 CS failed this past weekend while on track. It lost power, began to vibrate, displayed the CEL and low oil pressure warnings, and began to clank. The engine has 46K miles on it, including 5000+ on the track

Krokodil;
I am really sorry to hear about your engine failure, hopefully you can get it fixed soon and get it back on track, (and) on the track too.

This morning, while driving to work, I was planning to send you an email and ask you when I could stop to hear the noises made by the LWF... well, hopefully soon

Regards, Gilles

Krokodil,
This is the same failure mode my car had last year, it had about 10,000 miles on the odometer. We found connecting rod bearing material in the pan and went no further.
The dealership suspected what you have already said, rod bearing failure, intermediate shaft failure or severe oil ingestion.
At some point a rod/piston punched thru a cylinder wall because the pan was also full of coolant. Oil and coolant came out the exhaust the motor was making the sorts of noises no one wants to hear in their worst nightmare.

Good luck with a better fix.

Not sure if it will make a huge difference, had the X51 oil pan with the modified baffle installed during VOS install. I can find the part number if you're interested.

I am just coming off of a similar engine failure in December at the end of my first track day, at approx. 27,000 miles. Car now back, and I have to live through another 2,000 mile break in period after the rebuild. As a FYI, it is way harder to keep the engine under 4,000RPM this second time around; now why would that be? And I am surely going to have a hard time from my bride as I seek to take my DD to another track day (after the 2,000 mile period, of course)...

He had the Mantis sump extension as did I, although different versions, and there may still be oil starvation going on, perhaps not because the pickup ran dry in the pan but it may simply be that the pump is not strong enough to keep up under heavy load conditions, again a lot of unknowns out there, but I suspect one of the reasons why the new DFI motors have a completely new oiling system.

Wouldn't it be nice if Porsche had a motor swap program, bring in your existing M97 motor, get a new DFI motor in exchange.

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K-Man S

Ha Ha Ha. They wouldn't even help us with the hopelessly inadequate VOS!