Charles Navarro

There typically is some sort of visual stripe in every cylinder as the second piston ring is pinned on all pistons to keep the gap positioned away from the bottom of the cylinder. Normally piston rings rotate on the piston freely, but I presume they did this to reduce smoking at startup as the 2nd ring's primary job is oil control and if it ends up around the 6 o'clock position, engines will often let out a puff of smoke at startup as a result.

Honestly with the poor quality of the photos I couldn't really tell if there is scoring or not.

plpete84

Curious if you ever did used oil analysis (UOA) as this progressed and saw any increases in wear metals.

JustinCase

Yes, I did. Yes, there were.

plpete84

Thanks. What did the elevated values look like for wear? I'd assume aluminum and silicone were the main ones.

Sporty

"What did the elevated values look like for wear? I'd assume aluminum and silicone were the main ones".

FYI - they are in another fairly recent thread as I and others had asked a similar question. JiC had graciously provided the information - try doing a search, perhaps of his posts

plpete84

Thanks - will do! I don't frequent the 997 forum section much but have been following this thread as it has some great information. Must have missed that thread but will do a search...

JustinCase

Aluminum 16 (vs. 4 now)
Iron 20 (vs. 10 now)
Silicon 25 (vs. 9 now)

Fuel % 1.5 (vs. 0 now)
Flashpoint in *F 355 (vs. 430 now)

spessx

So I've read through this thread and wanted to see if there was any consensus regarding the 997.1 3.6L engine. Are they still susceptible to bore scoring? Are they as likely as the 3.8's?

I'm looking at a 2006 Non-S with 30k miles. It's at a Porsche dealer and I would definitely get a PPI done but it would be a car that I'd like to own long term.

Charles Navarro

Yes, the M96.05 3.6 engine is just as likely to score as the S's M97.01 3.8 engine. The majority of blocks coming in now to us for bore scoring are M96.03, M96.05, M97.01, and lastly M97.21.

Houndstooth

Anecdotally it seems the 3.6 is somewhat less prone to bore scoring than the 3.8. But by how much is unclear. My mechanic says he sees it way more on the 3.8 but there are also more 3.8s out there.

JustinCase

Since Charles Navarro's company remanufactures a high percentage of the scored blocks in North America, I bow to his perspective.

Graufuchs

Thanks for the insight and information.

I just purchased a 2008 911 Aero 3.6L w/ 18K. (prior ownership in CA/GA/NC).

In my attempts to prevent bore score I have taken the following steps:

-Driven DT40 5w-40
-L/N Magnetic Drain Plug
-Driven Fuel Injector Defender

Any other steps to be taken at this point?

Over its course of previous ownership the car has seen regular oil changes and over all in very good condition.

DME report was very good with sub (600) ignitions in range 1 and 2 and (3) ignitions in range 3. (0) in 4-6

The car is in a climate controlled Garage but I do live in the Northeast (NY).

Thank you in advance!

8KaboveMSL

I would also consider adding the LN engineering Low Temp Thermostat to your solution/prevention actions. It allows for the engine to heat up more evenly.

Another operational step you should consider is making sure you don’t run the RPMs above 3k until the engine oil is up to temp (185-200, not sure? I use 185-ish).

Charles Navarro

Congrats on your purchase.

I presume you had the cylinder bores scoped as part of a PPI so you know where you are starting from. We get asked this so often that we made a page on our website that goes over the main things you can do to minimize the chance of getting bore scoring:

https://lnengineering.com/products/w...e-scoring.html

Graufuchs

Thank you (for the Sunday response nonetheless)!

That was one thing I did not do (Bore-scope), shame on me, but I am here now. I briefly looked over that page the other day and it was helpful. Will give it a more in depth review.

That article is why I immediately changed the oil to the Driven Oil and took the other aforementioned steps.

I am tempted to perform a preemptive service this winter and change the plugs/coil packs/water pump and thermostat due to age. Thinking about injectors due to age as well.

I do really enjoy the car and its a more visceral drive VS the 991.2 (PDK). Blessed to have options.