2.7's overheated even when new

[mikeferg75]

Just tracked down the original owner of my 75 Carrera. Had a nice chat on the phone. He informed me that he didn't even own the car for very long due (a year?) to it overheating all the time, and the dealer ended up buying it back from him because they could not fix the problem...

Makes you wonder what kind of oil temps these cars ran when new and in perfect running order? And what they considered overheating at that time (1975)

Ferg.

[azasadny]

Does your car have the Carrera-style oil cooler in the front fender? Mine does and the temps never go over 190 degrees. I have the stock exhaust/heat exchangers and no catalytic devices on the car. It runs much cooler with Webers than it did with CIS, though.

[kach22i]

Originally posted by mikeferg75
the dealer ended up buying it back from him

I'd like to know how he did that.

Just wondering if it's to late to take my 1990 Geo Tracker back to the dealer.

[dd74]

I've heard Porsche air-cooled engines don't "overheat." Overheating occurs with water-cooled engines. Air cooled engines, when too hot, simply stop running.

[tonythetarga]

1975 was the first year for the thermal reactor exhaust and overheating was the big problem. Removing that and going with the 74 style heat exchangers or SSI's plus adding an 11 blade fan and an oil cooler, should take care of the overheating issues even in hot and muggy parts of the country.
What is currently on the car for an exhaust/heat exchanger system?

[mikeferg75]

car is still stock, (no extra cooler yet...) and appears to have had at least one engine build (11 blade fan, air injection disabled, SSI's ect) 109k on the car now. It could benefit from a cooler no doubt, but it's my DD and only goes on shot trips (11miles) to work, and weekend errands.

I agree on the "buy back" but he told me he had a real good association with the dealer at the time, and he was buying another.

Ferg

[ljibis]

I've heard this before. I read somewhere that the original heat exchanger-equipped cars burned up valve guides really quickly and required rebuilds as soon as 30-40k miles from new.

The manual for my '77 says oil temperatures up to 250F are okay, but anything above that should be investigated by a dealer. Knowing the state of oil technology back in the 70's, this is a bit worrying.

Incidentally, my '77 (20W-50 Castrol, no reactors, stock exchangers, stock "trombone" cooler) rarely gets much past 190F on the gauge. Once in a while it will tick towards 210 in heavy, stop-n-go traffic but always cools down once it gets good airflow again.

[donstevens]

Originally posted by ljibis
rarely gets much past 190F on the gauge. Once in a while it will tick towards 210 in heavy, stop-n-go traffic but always cools down once it gets good airflow again.

Considering that you live on the edge of the arctic circle that is not a surprise .......just kidding.

The fact that your car cools down with a little air flow indicates that the engine is healthy. Very healthy. Many older cars with heat issues won't cool off until they are shut off.

Don

[911pcars]

Originally posted by dd74
I've heard Porsche air-cooled engines don't "overheat." Overheating occurs with water-cooled engines. Air cooled engines, when too hot, simply stop running.

Don't allow thermal melt down to be your guide. 250ºF is too hot. Aim for something in the range of <210ºF. Temperature mitigation solutions for 75-76 911s are well-documented in the archives, in the internet and in print - some of which have been repeated in this thread.

Sherwood

[crosby50]

I love the fact that a dealer "buyback" is still running thirty years later!

[2.7RACER]

My 2.7 with the stock engine mounted oil cooler, 11 blade fan, no thermal reactors, has been running the tracks of Southern California and New Mexico for ten years now.
It has seen 250F temps rarely. I run Mobil One which helps.
Did a top end a couple years ago. Still runs 160psi plus compression at 5,000 ft.
Yes, the 2.7 was the low hp orphan, with lots of heat related issues. Today the survivors with all the known upgrades run as well as any.
Bottom line, the 2.7 bashers are living on old news.