I'm a advocate for low temp thermostats. The purpose of a low temperature thermostat is NOT to bring down the highest temps, but to operator more efficiently on the lowest threshold. JFP says it the best on this thread.

http://forums.pelicanparts.com/porsc...hermostat.html

 

Yikes. Now my head REALLY hurts Thanks for the information. The discussion in that forum/thread is a lot more in-depth than the first article. I had not heard about the potential for 'hot spots' with these engines. Now I'm leaning back towards a lower temp unit.

 

That was an interesting read and at least I have seen a reasoned explanation, even if I may not fully agree with it.

 

JAN2019 Update!! Finally tackled the cracked tank on my 01 Carrera Cab, which was diagnosed by the local Porsche dealer who did the limited PPI. Quite a job: 3 hours to get tank out; 1 hour to slide new one back in; 2 more to button it up. A couple key learnings: Fuel rail is in the way! Even dropping the engine only gave 95% of clearance needed. Recommend needle nose locking vise grips to deal with the Porsche spring hose clamps, if you don't have proper pliers. Also used cord to tie back disconnected hoses to give more room. Syphoned the antifreeze out using small tube to reach bottom of old tank, so it was nice and emply. Fingers crossed this is the needed fix.

 

Latest update: all those coolant loss and overheating issues in my '01 Carrera Cab were masking the underlying root cause of the overall problem ... excessive bore scoring and d-chunk failure. Interesting that none of the 'pros' (dealers and independent shops) could diagnose this correctly; they just wanted to throw more parts in to again be over-stressed and break. No mention of coolant loss, rapid temperature rise and combustion gases in the coolant seemed to ring a bell with them.

Problem reached the tipping point last December, leading to the need to replace the motor. I'm now patiently waiting for the shop to certify the replacement as healthy and install. Their goal is a Porsche that can drive from East Coast to West Coast and back without failure. That's a far cry from my not being able to drive more than ten miles without having coolant loss.

 

Ouch! Sorry to hear that. Shame that dealership techs couldn't properly diagnose this problem that has been well documented on the forums for so long.

What are your next steps? Rebuild the engine? Sell it off as-is?

 

Replacement motor was sourced from the West Coast ... also from a 2001 with slightly less mileage and a really clean service record. Not doing the LN sleeves but will do the IMS and AOS. Some of the new parts I just installed in the old motor before it failed (water pump, low-temp thermostat, coils, drive belt, 3-part hose) will be transferred over, as well as other parts that are better than the donor motor (alternator, idler pulleys, etc.). Will likely use the clutch and flywheel from my car, since they are quite new. All in, this will increase my cost of ownership by $15K, but hey, I will be able to drive it like I had hoped.

 

Have you bore scoped this donor motor?

 

Yes scoped, compression tested.

 

Yes scoped, compression tested.

 

My best advice is to replace anything that your budget will allow while the engine is out. Harder and more expensive the second time around.

If you decide to rebuild the engine, Jake Raby just release a 20-part series on engine assembly of the Porsche M9X engines. Always good to learn from the best.

 

I do follow Jake's postings, being a gear-head and structural engineer myself.

However. I don't have the budget for a 100% rebuild @ $20K+, on top of what I spent to buy the car. Best option was the vetted donor motor. Maybe if I were 40 years younger ...

 

Picked up my 01 Carrera Cab on Feb 18 from Butzi Gear after a motor transplant that took nearly 3 months. It's going to take me a year to unlearn watching my coolant loss and engine temp and not feeling like the engine was going to blow up at any moment. Like driving a normal car ...

 

"Problem reached the tipping point last December, leading to the need to replace the motor. I'm now patiently waiting for the shop to certify the replacement as healthy and install. Their goal is a Porsche that can drive from East Coast to West Coast and back without failure. That's a far cry from my not being able to drive more than ten miles without having coolant loss."

I hope you used a different shop than the one that failed to identify the problems the first time around... Good luck with the new motor - I hope you get way more than $15k of enjoyment out of it

 

yes it was adifferent shop recommended by a fellow PCA member who couldn't say enough positive things about the shop. The Porsche dealer and the other local, well-respected independent shop both missed diagnosing the root cause big time. Very sad that people pay them big bucks for expertise that just isn't there.