Welcome to RennTech.org Community, Guest

There are many great features available to you once you register at RennTech.org
You are free to view posts here, but you must login to reply to existing posts, or to start your own new topic. Like most online communities, there are costs involved to maintain a site like this - so we encourage our members to donate. All donations go to the costs operating and maintaining this site. We prefer that guests take part in our community and we offer a lot in return to those willing to join our corner of the Porsche world. This site is 99 percent member supported (less than 1 percent comes from advertising) - so please consider an annual donation to keep this site running.

Here are some of the features available - once you register at RennTech.org

  • View Classified Ads
  • DIY Tutorials
  • Porsche TSB Listings
  • VIN Decoder
  • Special Offers
  • OBD II P-Codes
  • Paint Codes
  • Registry
  • Videos System
  • and get rid of this welcome message

It takes just a few minutes to register, and it's FREE

Contributing Members also get these additional benefits:
(you become a Contributing Member by donating money to the operation of this site)

  • No ads - advertisements are removed
  • Access the Contributors Only Forum
  • Contributing Members Only Downloads
  • Send attachments with PMs
  • All image/file storage limits are substantially increased for all Contributing Members
  • Option Codes Lookup
  • VIN Option Lookups (limited)
Krokodil

Causes of M97.21 Engine Failure?

14 posts in this topic

The engine in my 2007 Cayman S 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)

Share this post


Link to post
Share on other sites
    You can remove these ads by becoming a Contributing Member.

The engine in my 2007 Cayman S 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)

Croc:

Sorry to hear that your engine gave up the ghost.

Take a look at Jake Raby's site for some solid suggestions: http://www.flat6innovations.com/

Also check out LNEngineering.com.

Both sites contain a wealth of information on possible upgrades.

Regards, Maurice.

Share this post


Link to post
Share on other sites

Not sure how you can cure or improve the IMS issue, the cayman already has a larger bearing and shaft fixing diameter. The root cause is that there is only one bearing taking all the load , so if it weakens then the deterioration is quick. Strengthened con rods should be available from 9ff or Ruf , I believe they developed their own for some of their hi performance models. Good luck with the rebuild please keep us updated with the improvments and mods applied, especially if you find something for the IMS.

Share this post


Link to post
Share on other sites

I have a 3.4 CaymanS apart right now (actually I have multiple M96 and M97's apart right now) You may know the engine :) It is the last one that was in Quinn's car here in SoCal. His car broke a rod bolt and let the rod cap fly around inside the engine. Now, the question is: How did that rod bolt break? I do not have access to his car, if I did, I'd check the range 2 overrevs looking for a mechanical overrev :(

We do have aftermarket rods/pistons/cranks/intermediate shafts available currently (I work VERY closely with the two companies mentioned above)

I received a phone call from the track within minutes of your engine expiring and I was making an effort to track you down and ask you what happened. I'm working on stocking dyno tested upgraded M96 and M97 engines for shops here in SoCal :) We are well on our way to providing people with a solid solution to these engine issues (and come in well under what the factory wants for a *questionable* replacement.

Is this a BBI car or a Essa car? Or Vision? or Speed Gallery? I'd like to see it the engine apart.

B

Share this post


Link to post
Share on other sites

Here is Quinn's old Cayman engine :( I have NEVER seen a piston split like this and I have building Porsche engines for nearly 23 years now. You can see in the second pic how the rod damaged the engine case while it was being thrown around :( That is a small hole to the bottom right of the cylinder where the rod bolt exited the case.

B

post-2685-1234598563_thumb.jpg

post-2685-1234598756_thumb.jpg

Edited by Brad Roberts

Share this post


Link to post
Share on other sites

Oh.. FYI: the M97's will not see the IMS failure the early M96's have experienced. Porsche went from a 5 chain cam drive system to a 3 chain. This took some of the stress off the IMS. They also beefed up the IMS rear bearing and support. They also used much much better material for the actual shaft itself which means less twisting :)

B

Share this post


Link to post
Share on other sites
Oh.. FYI: the M97's will not see the IMS failure the early M96's have experienced. Porsche went from a 5 chain cam drive system to a 3 chain. This took some of the stress off the IMS. They also beefed up the IMS rear bearing and support. They also used much much better material for the actual shaft itself which means less twisting :)

B

Brad,

Thank you for the photos and information. Yes, I know the engine and was there when it failed. According to Quinn there were significant high-range overrevs, so many that he doubts the accuracy. I assume it was quinn that called you from the track.

The car is at Vision and the engine was set to be torn down yesterday. There was bearing material in the pan and oil filter, but I do not know any more beyond that.

I assume if you contact Dwain he will share his findings with you, and vice versa. I hope to visit the shop on Monday PM.

Cheers,

Share this post


Link to post
Share on other sites

Thank you sir! I'll speak with Dwain later next week. I'm heading to Texas to deliver a Porsche. We are just trying to gather as much info about failures as possible!

B

Share this post


Link to post
Share on other sites
Oh.. FYI: the M97's will not see the IMS failure the early M96's have experienced. Porsche went from a 5 chain cam drive system to a 3 chain. This took some of the stress off the IMS. They also beefed up the IMS rear bearing and support. They also used much much better material for the actual shaft itself which means less twisting :)

B

I have seen a couple of IMS failure posts on 2006 > cayman engines , so though it may have reduced the risk , I still do not think its completely cured.

Share this post


Link to post
Share on other sites

The car is alive again. Fired last Friday 3/20 and was racing Saturday AM at WSIR.

The diagnosis was a failed #1 rod bearing, resulting in a broken craddle, two broken cases, a broken, rod, a couple of bad pistons, etc.

We purchased a used Cayman engine (from a 3.8 swap) with just over 2000 miles on it (Brad, you apparently know this engine) to use as a rebuild donor. Several chnages to improve oiling and reliability including a modified crank and installation of Carrillo rods:

dsc00869.jpg

Cheers,

Edited by Krokodil

Share this post


Link to post
Share on other sites

I am a new member and thought this would be the right place to post this question. I have a 2006 CaymanS with 12,500 miles of normal street use. The engine was burning lot of oil and the engine light came on a couple of times. Finally Porsche agreed to inspect it and reported the "left bank cylinders were scorched" and the engine was replaced. I am reading posts about other types of engine failure but I have not seen this?

Share this post


Link to post
Share on other sites
Oh.. FYI: the M97's will not see the IMS failure the early M96's have experienced. Porsche went from a 5 chain cam drive system to a 3 chain. This took some of the stress off the IMS. They also beefed up the IMS rear bearing and support. They also used much much better material for the actual shaft itself which means less twisting :)

B

Did this happen with the m97 motors only or did some of the 996 motors have this as well?

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!


Register a new account

Sign in

Already have an account? Sign in here.


Sign In Now