991.2 GT3RS Complete Engine Failure & PCNA Response
03-13-2021, 02:25 PM
#151
Burning Brakes
Neil great info thanks for sharing this.
Ian
Ian
03-13-2021, 10:19 PM
#152
It makes no sense starting this thread after issue was resolved for him. Especially still owning the car. Understand creating a public forum complaint if he got stuck with having to pay for a new engine but just not at all the case. Probably more too this too. And he’s rich so $3500 doesn’t matter. F off. Nightmare customer.
03-13-2021, 10:32 PM
#153
Ha! Well it doesn’t matter to the OP, 3500 is nothing to him (since he paid all cash). He’ll take that new engine and extended warranty, but couldn’t care less about the resale value of his car either. I’d only expect to be reading about this from a normal human if they didn’t fix the engine under warranty or if the same thing happened twice (to him).
03-13-2021, 11:05 PM
#154
I’ll add to the inquiries as well. Not a whole lot of failure data out there for the 991.1 RS. How does the operation differ on the 2016 991.1 RS vs the standard 991.1 GT3 engine? Same hydraulic operation and lash cap setup? What are things to look out for in this engine? My current RS ownership plan has no end date in sight and I’m curious what I can do to extend the engine life.
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Booth9999 (03-14-2021)
03-13-2021, 11:49 PM
#155
Rennlist Member
Niel,
Have you got pictures of the piston tops? How much are the "blocks" twisting? I assume the intake or exhaust stroke wouldn't matter because the lash pad cannot eject if the cam lobe is pressed on it. It would seem the 'finger block" would have to twist quite a bit to let a lash pad out for a walkabout. The fingers look forged and the finger blocks look to be alloy. I'm certainly no expert in this matter but having worked with a master builder of BMW engines and manufacturers of valve train parts (Supertech), I've learn quite a bit about the components and assembly processes. And have seen the result of tearing down for refresh or failure examination of race engine builds.
On the block fracture near the journals. Are these pictures from random refresh engines or engines that have had a catastrophic bearing failure? So much heat is generated when a bearing is spun that the block can become unusable. Especially in cast aluminum blocks.
I am very intrigued and am anxious to learn more about these engines from you and my automotive engineering buddies. In the meantime I'll choose to hammer my 991.2 RS as often as I am blessed to do so.
Have you got pictures of the piston tops? How much are the "blocks" twisting? I assume the intake or exhaust stroke wouldn't matter because the lash pad cannot eject if the cam lobe is pressed on it. It would seem the 'finger block" would have to twist quite a bit to let a lash pad out for a walkabout. The fingers look forged and the finger blocks look to be alloy. I'm certainly no expert in this matter but having worked with a master builder of BMW engines and manufacturers of valve train parts (Supertech), I've learn quite a bit about the components and assembly processes. And have seen the result of tearing down for refresh or failure examination of race engine builds.
On the block fracture near the journals. Are these pictures from random refresh engines or engines that have had a catastrophic bearing failure? So much heat is generated when a bearing is spun that the block can become unusable. Especially in cast aluminum blocks.
I am very intrigued and am anxious to learn more about these engines from you and my automotive engineering buddies. In the meantime I'll choose to hammer my 991.2 RS as often as I am blessed to do so.
Last edited by inverterman; 03-13-2021 at 11:51 PM.
03-14-2021, 02:19 PM
#156
The ONLY way to be certain of zero failure in any engine is not to start it. Porsche engines are not alone in this. Many other OE's are having issues, maybe not the same issues.
The photo's I posted are from engines we have disassembled. I know more than anyone else to what other issues may be out there. All I can share are what we have seen in engines we disassemble. However, some of the issues we have seen would not appear to be random, but more typical. If we saw main bearing failure and more bearings in the same engine and no block fatigue, I would assume there could have been an oil starvation issue. But the same bearings in 2 engines and the blocks cracked give me cause to think this is more inherent. We did twist the block with the "girdle" and oil pump in place and it was alarming how much it moved. The "girdle" is doweled to some of the main caps but not all. The rear block "ear" where the crack occurs is not supported or braced back to the main block mass.
What causes the block to move I have no idea. Is it the transmission or the shifting, I don't know. We have a lot to learn but not a lot of examples to work with. The lash cap issue is more about the valve train now "solid" and the lash pad not "captured" in the retainer. This problem has been seen before in motorsport and corrected. It would be interesting to know if Porsche have corrected this in their race engines. There is no way they can run the same design and get away with it. If its happening in the street engines it would happen in the race engine. We have a "repair" for this, but like the 991.1 hydraulic finger issue, we are up against the warranty. We just have to wait until its our turn to "fix it". In the meantime we will proceed with the "hot rodding" and hopefully have some success with these engines.
The photo's I posted are from engines we have disassembled. I know more than anyone else to what other issues may be out there. All I can share are what we have seen in engines we disassemble. However, some of the issues we have seen would not appear to be random, but more typical. If we saw main bearing failure and more bearings in the same engine and no block fatigue, I would assume there could have been an oil starvation issue. But the same bearings in 2 engines and the blocks cracked give me cause to think this is more inherent. We did twist the block with the "girdle" and oil pump in place and it was alarming how much it moved. The "girdle" is doweled to some of the main caps but not all. The rear block "ear" where the crack occurs is not supported or braced back to the main block mass.
What causes the block to move I have no idea. Is it the transmission or the shifting, I don't know. We have a lot to learn but not a lot of examples to work with. The lash cap issue is more about the valve train now "solid" and the lash pad not "captured" in the retainer. This problem has been seen before in motorsport and corrected. It would be interesting to know if Porsche have corrected this in their race engines. There is no way they can run the same design and get away with it. If its happening in the street engines it would happen in the race engine. We have a "repair" for this, but like the 991.1 hydraulic finger issue, we are up against the warranty. We just have to wait until its our turn to "fix it". In the meantime we will proceed with the "hot rodding" and hopefully have some success with these engines.
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03-14-2021, 04:37 PM
#158
I can understand your frustration, but imagine if Porsche had denied the warranty entirely if the car was used on track (as they're legally entitled to do)? Since the failure occurred on the road, you likely would have received coverage eventually (but could be an unpleasant process)...
Some other manufacturers might have handled this in a much more frustrating manner.
Some other manufacturers might have handled this in a much more frustrating manner.
03-14-2021, 05:12 PM
#159
Addict
Rennlist Member
Rennlist Member
I assume you either don’t own one of these cars or didn’t read the manuals that came with it. It is specifically warranteed for track use. PCNA would be in an extremely interesting position if they tried to deny warranty based on track use for an un-modified car. Oliver has an excessive expectation of what PCNA will do - what he got was slightly beyond standard for engine failures in his geographical area - but his expectation of warranty coverage even for a (quite lightly) tracked car are spot on.
Last edited by GrantG; 03-14-2021 at 05:14 PM.
03-15-2021, 12:14 AM
#162
Race Car
The ONLY way to be certain of zero failure in any engine is not to start it. Porsche engines are not alone in this. Many other OE's are having issues, maybe not the same issues.
The photo's I posted are from engines we have disassembled. I know more than anyone else to what other issues may be out there. All I can share are what we have seen in engines we disassemble. However, some of the issues we have seen would not appear to be random, but more typical. If we saw main bearing failure and more bearings in the same engine and no block fatigue, I would assume there could have been an oil starvation issue. But the same bearings in 2 engines and the blocks cracked give me cause to think this is more inherent. We did twist the block with the "girdle" and oil pump in place and it was alarming how much it moved. The "girdle" is doweled to some of the main caps but not all. The rear block "ear" where the crack occurs is not supported or braced back to the main block mass.
What causes the block to move I have no idea. Is it the transmission or the shifting, I don't know. We have a lot to learn but not a lot of examples to work with. The lash cap issue is more about the valve train now "solid" and the lash pad not "captured" in the retainer. This problem has been seen before in motorsport and corrected. It would be interesting to know if Porsche have corrected this in their race engines. There is no way they can run the same design and get away with it. If its happening in the street engines it would happen in the race engine. We have a "repair" for this, but like the 991.1 hydraulic finger issue, we are up against the warranty. We just have to wait until its our turn to "fix it". In the meantime we will proceed with the "hot rodding" and hopefully have some success with these engines.
The photo's I posted are from engines we have disassembled. I know more than anyone else to what other issues may be out there. All I can share are what we have seen in engines we disassemble. However, some of the issues we have seen would not appear to be random, but more typical. If we saw main bearing failure and more bearings in the same engine and no block fatigue, I would assume there could have been an oil starvation issue. But the same bearings in 2 engines and the blocks cracked give me cause to think this is more inherent. We did twist the block with the "girdle" and oil pump in place and it was alarming how much it moved. The "girdle" is doweled to some of the main caps but not all. The rear block "ear" where the crack occurs is not supported or braced back to the main block mass.
What causes the block to move I have no idea. Is it the transmission or the shifting, I don't know. We have a lot to learn but not a lot of examples to work with. The lash cap issue is more about the valve train now "solid" and the lash pad not "captured" in the retainer. This problem has been seen before in motorsport and corrected. It would be interesting to know if Porsche have corrected this in their race engines. There is no way they can run the same design and get away with it. If its happening in the street engines it would happen in the race engine. We have a "repair" for this, but like the 991.1 hydraulic finger issue, we are up against the warranty. We just have to wait until its our turn to "fix it". In the meantime we will proceed with the "hot rodding" and hopefully have some success with these engines.
Cancel culture now for engines, eh? The boys at Porsche saw fit to run this engine in competition where it was extremely reliable. Now we're hearing in this thread that the engines are defective? Could there be locally defective materials instead? I'm still not entirely buying this story. Guess I need more data.
03-15-2021, 10:57 AM
#163
OK so now I have to ask...going to a solid valvetrain in the 991.2 engines was to improve reliability, not make it worse. Add to this you don't have to make adjustments for 300,000 km per AP. So I would ask for more specific data here to challenge the claim that this is a systemic issue with 991.2 engines failing. For example, how many in the field and what percentage of engines have failed? To me that's an important statistic vs. automatically turning this into a "991.2 engines are defective" rant.
Cancel culture now for engines, eh? The boys at Porsche saw fit to run this engine in competition where it was extremely reliable. Now we're hearing in this thread that the engines are defective? Could there be locally defective materials instead? I'm still not entirely buying this story. Guess I need more data.
Cancel culture now for engines, eh? The boys at Porsche saw fit to run this engine in competition where it was extremely reliable. Now we're hearing in this thread that the engines are defective? Could there be locally defective materials instead? I'm still not entirely buying this story. Guess I need more data.
I come from the Motorsports world and those engines ran a lot more RPM and never had lash cap issues. I come from the world where when something breaks or is wrong I fix it. In motorsport, you never left anything to chance. 1 failure was 1 failure too many.
My sarcastic mind thinks here, you are stuck on the side of the road late one rainy night and you turn to your passenger and say. statistically this should not have happened".
03-15-2021, 11:04 AM
#164
We have been inside both engines. Both have different issues. The 991.1 had the finger follower issue, the 991.2 has block and lash cap issues. To say one is better than the other, I cannot say this. Not enough time on either yet to make that determination. Both have what I would call a serious fault. As with most OE's today, faults are taken care of with warranty's. Its how they take care of them that becomes important. Unfortunately it seems to be replacement only and not a fixed solution.
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oliver991 (03-15-2021)
03-15-2021, 12:17 PM
#165
We have been inside both engines. Both have different issues. The 991.1 had the finger follower issue, the 991.2 has block and lash cap issues. To say one is better than the other, I cannot say this. Not enough time on either yet to make that determination. Both have what I would call a serious fault. As with most OE's today, faults are taken care of with warranty's. Its how they take care of them that becomes important. Unfortunately it seems to be replacement only and not a fixed solution.
Thanks Neil. I understand the finger follower issue as it related to the early 991.1 - specifically the standard GT3. They addressed this with the 10 year warranty and replaced some to the "G" series engine, correct? When the RS came out in 16, the issue was mostly "resolved" at this point (material was updated?) if I recall correctly from other discussions. The RS engine (991.1) is essentially a stroked G series motor, right?