Maintaining and repairing an air-cooled 911? Easier than you think.

Update by David S. Wallens to the Porsche 911 Carrera project car
Nov 13, 2024 | Porsche, Restoration, Porsche 911 Carrera

Photography by David S. Wallens

The Porsche coasted to a stop–silently, without any warning. No glowing lights on the dash. Yes, plenty of gas in the tank.

I was returning from a PCA get-together at a local Porsche shop. The irony wasn’t lost upon me.

Fortunately traffic was light, the sun was shining, and the grassy right of way was welcoming.

I popped the flashers and felt smug for a moment. I knew what to expect.

When I bought this 1984 Porsche 911 Carrera, I was told to carry a few spares, including a DME relay. This relay–those three letters short for digital motor electronics–serves as the relay for the fuel pump: When the engine turns off, the fuel pump turns off.

If the engine is running, then this relay is energized–and that takes a toll on its life, hence why it’s a common point of failure. Depending on the supplier, the source and the time of day, replacements range from a little shy of $40 (aftermarket) to about $120 (Porsche Classic Genuine Parts). The spare won’t take up much room in the glove box.

This relay can be found below the driver’s seat, and I was told swapping it takes just a few minutes. Which it did.

And still, nothing.

The usual suspects and connections looked good. I punted and called a tow truck.

This is where my mind started to race. Images of timing chains akimbo filled my mind. Or maybe even worse.

The diagnosis once at the shop? An unplugged crank position sensor. It wasn’t broken, just unplugged.

And that more or less sums up the past 15 years with the Porsche. Occasionally something unpleasant will crop up, but other than the engine work discussed in the last issue, so far, knock on wood, the fixes have been easy and far in between.

In 15 years, the Porsche has gone on the wrecker once–and turns out nothing was even broken. We once split a shifter bushing–less than $16 to replace the set–and also installed a headlight relay kit.

First, second, third, fourth, third.

Third?

Up and to the right usually engages fifth gear. Where did fifth gear go?

My next thought: This is going to be expensive, isn’t it?

This was a couple of years later, and I was out for a simple drive. Again, a nice, sunny day.

The lack of fifth gear caused worry but didn’t send me to the sidelines. I was still motoring, just without top gear.

The glimmer of hope: I could feel–and hear–something unwell deep inside the shifter mechanism. An easy fix, right?

[Our five-speed Porsche decided to become a four-speed]

Modern shifters–whether involving a lever, knob or button–usually employ electronics. Back in the day of the air-cooled 911, shifting was done via a linkage–and here that linkage covers a bit of ground.

Four plastic bushings help make the magic happen: one at the base of the shifter itself, two for the shifter coupler, and one that guides the linkage through an opening in the bodywork. I’d split the last one on that list, preventing the linkage from properly articulating. The complete set so all four bushings could be renewed: $15.67 plus shipping.

The other snafus I’ve experienced over the years could be categorized as typical old car stuff–torn axle boots, dead battery, trunk struts that no longer wanted to strut–although two issues unique to the air-cooled 911 have occured. Both involved the headlights.

The first problem to hit: a burned-out high beam switch. The unit includes the stalk itself, and replacements now run north of $300. Once you pull the steering wheel, it’s just a matter of removing and replacing the offending part.

Here’s where an ounce of prevention comes in. The factory wiring sends current from the battery through that switch, so to preserve that replacement, I fit a relay kit from a small firm called JWest Engineering. Now current bypasses the switch and goes straight from the battery to the headlight circuit. The kit currently retails for $55 and is an easy install–no multimeter or specialized equipment required.

I’d eventually have a problem with that replacement high beam switch: no low beams, only high beams. The fix involved slightly bending an electrical contact back into position.

What do all of these issues have in common? Where an air-cooled 911 might seem exotic and complicated, the fixes, at least so far, have been fairly quick and easy.

As a bonus, the parts have been readily available from a large number of vendors. Some even offer the components from multiple suppliers at various price points.