If no PPI, what to look for?

[skips]

I am going to look at a 2.7 tomorrow. It looks nice in the pictures, runs, car looks nice, etc. I have some mechanical skills, none specific to Porsche 6. I understand the 2.7 needs the studs upgraded.

Short of a trained Porsche mechanic looking at it, what would you do to assess the engine condition on a first look/first drive basis? I think the seller wants to move it so I might want to buy it if price is right. Thanks Skip

[Oh Haha]

Have you owned a 911 in the past ot have any knowledge about the car?

If not, I would suggest posting your location and maybe a Pelican could hook up with you and check it out.

Besides the common areas one would check out when purchasing a used vehicle I thoght of these that are unique to the Porsche you are going to look at.

Blue smoke, if any, on start up should dissipate after about a minute or so. This would indicate that the valve guides aren't gone. A little smoke is common.

Excessive engine clatter or anything that sounds like a bunch of marbles in a tin can should be your clue to run away. Screaming is optional.

Oil leaks are common so unless there is an Exxon Valdez size puddle don't be too alarmed.

A smooth shifting transmission is a plus. The 915 5 speed can be a bit balky especially if you are used to modern, smooth shifting transmissions.

I know others will post more so I'll stop now.

[dad911]

Cut a deal, contingent on getting a PPI, then get one.

I don't want to be a jerk, but there is so much to look for, no matter the price, it could cost you more to fix an early car than it is worth.

Engine - compression test, check studs, leakdown test.
Chassis - rust & collision repair. Often not easily visible.

[Aurel]

You need to find out if the motor has been rebuilt with the necessary upgrades. From the outside, you can look for:

- 11 blades fan
- Pop off valve in the air box
- Oil lines on the cam chain box covers indicating hydraulic carrera tensioners.

In general, check for oil leaks at the base of the cylinders, that would be a sign of pulled headstuds.
Look for a clean engine, indicating it was well maintained.

While driving, check the oil pressure. Should be about 14 psi per 1k rpms. Look for smoke, that would indicate worn rings. Smoke on deceleration would be worn valve guides.
If the gearbox grinds while shifting gears, syncros need to be replaced.

Listen for valve noises, exhaust leaks. There is a typical pop pop noise from leaks at the cylinder-heads when headstuds are loose.

All of that can be costly to fix. The 2.7 has a magnesium case that needs expensive machining to rebuild properly. Better find out in advance if the costly upgardes were done. You can get lucky, but in general there is no such thing as a cheap 911: it will cost you at least $15k, either you pay upfront or afterwards. Good luck.

[skips]

Thanks for the thoughts so far. I am pretty comfortable checking out the rust issues/general chassis/brake stuff/general mechanical (hopefully so, I'm building a kit aircraft, but there is this one reoccurring dream...).

Its a 2.7 retrofitted to a 1969, with the 901 type gearbox, someone had to be paying some attention, the general appearance is it was done with care-tin is painted and installed properly, exhaust looks good, hoses look hooked up properly (no bolts plugging vacuum lines), not a hacked up appearance. However, the present owner doesn't know any history of the engine or details on the work, I didn't push on how he acquired it yet. He said it has the original CIS injection, does that sound right for a 2.7?

My plan is to give it a good looking over, warm it up for 20 minutes or so, looking for smoke, noises, go for a leisurely "round the block", and if it feels good ask the seller to run at 75 mph for 20 miles down the interstate with pushing up to whatever feels safe. Then watch it idle for another 10 minutes.

What should oil psi be at start up, warmed up idle, 75mph, 100mph, and hot idle before shutdown? Cylinder head temps I assume should stay under 350F?

Should this reveal most motor problems? I assume that if the seller knows it is junk he won't do more than let it idle, what would I be listening for that could be an engine killer if run hard? Are the likely problems in the valve train/chains? I can detect a bad rod bearing in a chevy, is this the same generally? If I hear marbles in a can, is that a predictable problem of just a general sign of something ready to fail?

I'm hoping the body/interior looks as good in person as the pictures and that the seller wants to move it quick like tomorrow.

Any more tips for the foolish? Thanks Skip

[Gogar]

Originally Posted by skips

Its a 2.7 retrofitted to a 1969, with the 901 type gearbox, someone had to be paying some attention, the general appearance is it was done with care-tin is painted and installed properly, exhaust looks good, hoses look hooked up properly (no bolts plugging vacuum lines), not a hacked up appearance. However, the present owner doesn't know any history of the engine or details on the work, I didn't push on how he acquired it yet. He said it has the original CIS injection, does that sound right for a 2.7?

My plan is to give it a good looking over, warm it up for 20 minutes or so, looking for smoke, noises, go for a leisurely "round the block", and if it feels good ask the seller to run at 75 mph for 20 miles down the interstate with pushing up to whatever feels safe. Then watch it idle for another 10 minutes.

What should oil psi be at start up, warmed up idle, 75mph, 100mph, and hot idle before shutdown? Cylinder head temps I assume should stay under 350F?

Should this reveal most motor problems? I assume that if the seller knows it is junk he won't do more than let it idle, what would I be listening for that could be an engine killer if run hard? Are the likely problems in the valve train/chains? I can detect a bad rod bearing in a chevy, is this the same generally? If I hear marbles in a can, is that a predictable problem of just a general sign of something ready to fail?

I'm hoping the body/interior looks as good in person as the pictures and that the seller wants to move it quick like tomorrow.

Any more tips for the foolish? Thanks Skip

To be honest, letting it idle for 20 minutes is a waste of about 15 minutes.

+1 to what Aurel said. In general:

Look for an 11-blade fan. It is also very important that the exhaust/emissions stuff has been taken care of. (most likely it has, but you NEVER KNOW.) If you find a pair of SSIs or similar, that's good.

Make sure you're around when it starts from DEAD COLD, to see what happens. Lots of the common CIS problems occur cold.

When it idles, llisten to the idle. An occasional "poof, poof" could mean ANYTHING, from a dirty injector to a bad head stud.

Really, just judge it when you drive it. When the engine is warm (180 degrees+), expect 10-15 PSI per 1000K of RPM.

If you and the seller have time, get it hot (200 degrees+), and shut it down. Start it back up. Make sure the starter doesn't bind hot. Wait 5 minutes. See if it starts again hot. Troubles starting hot could mean a fuel pressure/vapor issue. Not a big deal, but realize you're going to be messing with it.



Really, if the engine is clean and has obvious care, that's a good sign. If done properly, a retrofit or conversion can be a sign of stuff having been done properly.

That said, why would someone go to all the trouble and then pick a 2.7? You never know.

[Jack Olsen]

You don't want to buy a mag-case 911 without a PPI.

Even for free, many of them are going to be money-losing propositions.

It's risky to buy any 911 without a PPI, but the 74-77 cars are common first-time Porsche owner headaches because they often appear to be 'bargains.'

There are many good ones out there. Virtually all of them will come from owners who agree to a sale with a PPI. There are also many out there that are going to cost you thousands of dollars no matter what you pay to get your name on the pink slip.

[EarlyPorsche]

If the chassis is nice, and the price is right, you could always swap out the 2.7 down the road. Price will be the determining factor. Since it is a longhood its value is near the peak of Porsche values so the engine in that chassis could be a hopped up 7R case or it could be a stock 2.7 dropped in for value. I would at least have a Porsche friend help look it over but if you get it for what you think the chassis minus the engine is worth then the engine is just a bonus. If you pay more for it just factor in average used engine prices to install. That car should have had a magnesium 2.0 installed from the factory which is cheaper than the 64-67 aluminum 2.0 (for when you price another engine IF need be).

[73rustbucket]

Oil pressure at idle does not matter. Should be 1 bar/ 1K RPM. 1bar= 14psi.
A good trick to finding low compression is to disconnect the coil, crank the engine. You should hear even frequency of the compression. If a cylinder is very low, you will hear it go faster every 6 pulses. This method has a threshold of only 15% or worse detection.
That being said, unless it is quite cheap, consult a more knowledgeable person (although I didn't).

[skips]

Drove 2 hours to look at it, generally a nice driver what needed a few things. Seller finally admitted the Fuchs were fake (looked nice though). Engine had been rebuilt as evidenced by the digital photos of the pcs, too bad he didn't keep any receipts or old parts. Wouldn't attempt a start because of wiring issues, didn't? understand that a jump box could at least get it to turn over to listen to. His mechanic buddy/helper had 3 Porsches, must have known that.

Anyway, that scared me off. My luck would be a black hole for money. Thanks to you all for the input, Skip

[Zef]

If no PPI, what to look for? ...A PPI

[carlosR]

Don't feel bad, good that you walked away. There are plenty of them out there as has been said. You will know when you meet the right one, kind of like a partner! Prices are good for buyers now, good luck.