The lack of discernible progress from E to F to G would suggest otherwise.

Unless Porsche does know and they just want to keep the dealership mechanics occupied.

 

Cmon now. Read my second statement. And, remember this is porsche. How long was the split case mezger design around??? This car has been out 3 years. I expect progress by 2025.

 

So far no real facts on any G failures. Just rumor and anecdotal.

Trakcar and other high mileage RSs with lots of track miles seem to indicate Gs are in the clear especially in view of oil analysis results.

 

Seems like we could find a cut off point either via a manufactured date or the VIN to reduce concern.

 

Did any of the finger follower failures show up on an oil report?

I have never seen anybody checking on that.

 

Way too premature. Our G engines have had relatively little use yet. Most are 1 year or less old. Peter has been changing oil very regularly and using the car mostly for track work. He and Joe are the only two guys I know around here that have put that kind of track mileage on a G and their cars are mostly dedicated to track work. With the E & F cars dedicated for track work seemed to do better than those that were multi use. Also the DLC doesn't turn up in oil analyse (its not a metal) so that method is quite ineffective for understanding. We still have F engines that have done the same or more mileage of Pete and Joe with no issues (yet). One was Rich till very recently, the other OrthoJoe and Manifold. These are all 6000+ track mile GT3s without any work to their engines, but in all three cases the cars were used mainly for the track (and getting there).

Ill put it out there that if Joe or Peter had their top end opened they would find the delamination is already starting to some degree on the followers. Id hesitate to say the same for my G engine. fitted in Feb now done 10K km inc 2000km of track work. These engines dont have the DLC cam lobes.If someone wanted to do a whip around Id be prepared to have my engine opened up in 5000km and another 1000 track km time next year to determine how the G engine is holding together - all documented and photographed etc. I expect it to be far better than my E engine, but i do expect it to have started showing these same signed of wear. I think PAG have an issue with this whole design and that we will be seeing the same engine in the 991.2 GT3 etc just with more DLC coated components in it to try and extend the service cycle...

 

Macca thanks for clarification that the DLC
Doesn't not show in an oil analysis
I thought the case
But once the DLC wears thin
Isn't metal then being wore?
Which would show in oil analysis
Giving notice of trouble ahead , no ?

 

Macca: Thanks. Question. Would not an oil analysis also include a particulate count and micro scopic analysis for the non ferrous contaminates that could identify DLC?

Deacon also made a good point. If you see sign of ferrous contaminate it would likely indicate DLC has worn.

Does't a CEL also record if its a timing issue as far as the valves whiich would indicate cam/follower issue??? The nature of the CEL code is critical/important. Were CEL that eventually turned up showing worn followers/cams the same code for the same cylinder(s).

 

Yes, I believe an oil analysis report could be tailored to identify the presence of DLC particulate, however you would need to determine the make up of the DLC in the first instance and provide this data to the laboratory. The reports I have seen to date (Blackstone etc) are generic and are looking at ferrous composition.

It is true that if the DLC debris is not effectively screened it could indeed lead to pitting of ferrous surfaces, crystallization leading to further wear which would in turn in time show up in a traditional oil analysis report. The G engine uses a redesigned oil filter. We do not understand why, but if we assume its more effective than the earlier E & F filters then I think we can accept it is doing a better job of screening contaminates from the oil before it is being recirculated. It could take some time for DLC deposits to create ferrous metal wear at a level that is significant.

Richards situation is still unknown. He had more track miles on his F engine than almost anyone here and he pushes the car. He did have a CEL missfire code but replacing oils/plugs appeared to resolve this. Historically we have seen that engine that eventually "fail" have sometimes also shown prior CEL codes that appear to have been remedied by new coil packs etc. The factory have (at least in ROW land) shortened the replacement cycle of the plugs (now 12 months 10k km in our market). Its possible fresh plus/coil packs can help mask the effect of the worn finger follower pads and resultant timing deficits for a period of time. Its also possible Richards engine was already loosing DLC coating and that this particulate had had time to work its way through the system and damage the crank bearings/journals creating the resultant rod failure. However, its way to early to speculate that is the case. We will know soon enough.

The factory move to the G1 engine with DLC cams (911R and later RS) for a reason. Reducing the rev-line to 8650 in the RS and 8500 in the subsequent R may indeed provide more latitude of timing tolerances before a resultant CEL miss-fire code - Im not a mechanical engineer so I do not know for certain if this is the case, but I suspect timing intervals become more critical at higher rpm. However the reduction in rpm limit and any adjustments in the sensitivity of the system by the ECU may not have eliminated the issue, only delayed the occurrence of the CEL.

 

Even though DLC isn't directly measurable currently, oil analysis for my engine did show higher than average aluminum and iron indicating high wear. That was true at 5000 miles but that is often the case for new engines and after the first error occurred at 10k. I think more frequent routine sampling would show wear before the error and significant damage happens.

In my case, I just got approval for an engine replacement and the order went in for one from Germany today. Hopefully will get here soon and I start the break in.

 

Nice. Glad to hear PAG is still doing full motor replacements.

 

CD
That's great news you'll be getting the most up to date new G engine , also good to hear for your concerned brethren in our GT3 community . Congrats Fingers crossed for quick shipment and
Winterfest ready

 

Re DLC in oil

DLC is mostly carbon swimming in a sea of carbon based fluid. Think school of minnows well mixed in a large ocean of oil.

Maybe sub PPM (mg/kg oil) level.

I would say that the mg of scraped off DLC very difficult to isolate and analyze by most tests and has almost no effect on engine wear. Just too big of an oil ocean, and a hell of alot of other contaminants as well.

 

Since they aren't making 3.8s on the line, I was hoping for a 4.0L being shipped. Would make a great Christmas present!

Seriously, this decision was the result of great support from the entire dealer team and PCNA.

Carmen

 

Carmen. Fantastic outcome. You will get the G1 engine with DLC cams. Make sure you post the engine number or better still the stickers on the outside of the shipping crate for the engine for us. Well done perseverance paid off!