How much oil do 2.7s leak?

[davidbir]

Hi everyone, my first post.
While not new at all to classic cars I am new to Porsche so please be gentle with me.
Yesterday I went to see a '77 2.7 that I was seriously considering buying after reading the owners description and viewing photos. While the car is bodily good, apart from the sunroof being hacked out and nothing put in to replace it, I am very concerned about the engine. Upon starting, which it does easily, I expected to hear a "whoop" when I blipped the throttle (It has headers and minor mufflers), what I heard sounded more like an asthmatic Beetle and probably running on 4 or 5 cylinders only. Upon test driving it, I was very disappointed with the lack of engine power. The engine leaks LOTs of oil. Are these symptoms of broken/pulled head studs? This car has been discussed on this forum, the owner told me, and he said that "A leak on the intake side" was the problem with the engine.
Many thanks, David B

[equality72521]

Sounds like head studs to me based on what I've read here. I would not touch that car without a PPI at the very least. Maybe not even after one unless the price made it worth it.

[relayswitcher]

Dave, listen up and I will save you alot of frustration. Unless you bought it already and have found out all I'm saying to you here now. The 2.7 engines are notorious for the head studs pulling. I'll try not to be too technical in my description so it's easy to understand. These 2.7 engines never made it much passed 70k miles before you heard the sound you hearing. I'll tell you why.... These were some of the first years Porsche had to place smog devices on the cars and a round piping placed on either side called "thermal reactors" about the size of a loaf of english muffins. These reactors got extremely hot and positioned directly under the heads and valves and cam towers ( the whole length of the studs to the outside of the engines) they heated up the studs making them expand and contract with engine off then engine on. This caused the studs to start coming away from the where they are threaded to the case. And it didn't help that the threads were very fine, too. To make things worse, heat rises of course, and all the assembly glues, gaskets, and rubber seals were subjected to these quick fix for smog inventions.
SO what most people think is an exhaust leak and sounds just like one, is actually the head studs and the heads and towers pulling away from the engine case making a leaking air sound which is really compression loss. So guess why the car has no power as you say. My advice to you is if you like the car buy it, but for the correct price and with the idea that the engine is going to break down in a matter of a few hundred miles perhaps. I wouldn't put one single more mile on the car because you can make it worse and more parts to replace. And really it needs to be completely rebuilt. Bare in mind that you have to smog this year of vehicle... In California anyway. If you buy it you will need to do a few things on the rebuild to make it last.
1. Take the case to a machine shop that does Porsche and have them insert STEEL coarser threads into the engine case halves.
2. Have an exterior oil cooler placed on the car. Get a new one not some used junk from a swap meet.
3. Remove the reactors and toss them to a metal scapper. Don't know anyone who whats them on their car. Pay a smog fine rather than rebuild your engine again... I say.
4. Lastly, if you buy a 2.7 Porsche make sure the seller has done all this to the motor and ask for machine shop receipts to prove it. Otherwise , someone is trying to sell you their problem. Also, ask if it has the smog pump on the car, otherwise you are out of look passing smog.... in California. Any questions please feel free to ask. Relayswitcher

[2.7RACER]

Hi David,
As a long time owner of a '76 2.7, I'll say the car you looked at sounds like a real dog.
A hacked out sunroof? Oil leaks, lot of oil leaking? No power? Running on 4 or 5 cylinders?
This is a parts car.
The cost to bring this car back to some semblance of correct will be more than any ultimate worth, lots more.
My 2.7 race car with 130,000 mile does not leak. It took me some work to fix it but it is dry today.
Do yourself a favor and look for a dry, solid 3.0 or 3.2. You'll pay $12 to 15K for a good one.
Absolutley, get any 911 examined by a independent Porsche shop. It'll cost from $100 to $300. It can save you thousands.
Many of these shops know where the good used Porsches are and the ones to stay away from.
Walk away from the car you described.

[911pcars]

Just to be a little more accurate, the studs may have pulled because they, being steel, don't expand as much nor at the same rate as the aluminum cylinders. The add'l length of the heated cylinders puts strain on the aluminum case threads and they eventually fatigue and fail. The ultimate solution is to repair the case threads with threaded inserts (steel).

Or it could be a head gasket leak caused by the aforementioned loose studs or just a failed head gasket.

Or it could be a broken spark plug wire.

Cardboard is a Porsche-owner's best friend, but nevertheless, oil leaks could be minor or major depending on the source.

If the car is otherwise in good shape, the price is right and you like projects, follow the suggestion and have it inspected by a good Porsche tech.

What is the owner asking for this?

Sherwood

[FrinkFrog]

David,

So far, everyone is advising you to be careful with this car. I would echo those sentiments. In addition, what no one has mentioned as probably the real cause of pulled head studs in 2.7 engines is that the 'mid-year' cars ('75-'77) that used this engine had increased displacement using the older, magnesium cases. Magnesium, being very light, but very soft, succumbed to the limits placed upon it b/c the increase in cylinder diameter (larger displacement had to come from somewhere) left little metal to securely anchor the head studs. When the additional heat generated by all of the anti-smog devices added to these engines (this was about the time that the US gov't. was exacting increased limitations upon engine exhaust), the result was rapid failure of the case material in holding the head studs in place. I have one of these engines, but I bought the entire car for $4k and it is completely original w/only 36k miles on it. The plan is to drive it gently until it will need rebuilding, or in time, shop for a 3.0 or 3.2 engine, which came out next (beginning in '78 with the SC cars). This is when Porsche switched to aluminum cases, proving to hold the head studs securely. These newer engines were not without their own issues (breaking head studs), but are infinitely stronger and arguably, better engines than the 2.7s. Keep shopping until you find either a mid-year car that has PROOF it has had all updates necessary to insure longevity or better yet, an SC car with the aluminum cased engine. And as always, the PPI is a must.
Kirk

[relayswitcher]

Dave, None of us should assume you have no talent for learning to rebuild your own engine and a new sunroof is not impossible. Do what I did years ago and get a good rebuild book. A factory set of repair manuals is nice but I found not much better than the terrible black and white pages of a Haynes book... which I say stay away from, too. Fortunately some nice guys put a great book together a few years ago call How to Rebuild and Modify your 911 Porsche. And it's in color and very clear pictures. Some ask $30-35 dollars for it. I got it on line at Wal-Mart.com believe it or not for 18.95 +tax. It's only on line. They also have the 101 Projects for your Porsche.... same price. If you can follow written instructions and ask a jizzillion questions and find the popular machine shops you can do it. Be aware there are some repair shop people out there that just pricks about helping you and then there are those who have the nature to help. You see, if you haven't already. R.

[davidbir]

Many thanks to all above who responded.
I only just checked the thread again after receiving the first response and thinking that was all I was going to get.
I decided to buy a 82 SC instead and so far I am delighted! What a driver's car! I have owned many 'old' English sports cars and have vintage raced many more but this Porsche is the bee's knees.
The '77 is still for sale....