Fixing minor problems

24 September 2001

I bought the smurf-blue (Schlumpfblau) Porsche on a Tuesday, and drove it around for the rest of the week. These are the only real problems I discovered during that time:

1. Front suspension bounces all over the place at speed; probably due to the front end being lowered.

2. A lot of vibration at idle.

3. Shifting is incredibly sloppy; it's very easy to shift into reverse when aiming for second.

4. Speedometer cable squeaks.

5. Serious lack of power when starting up from idle; carbs probably need re-jetting.

At the weekend, I set out to solve some of these problems. Because this first required removing the other Porsche from the garage (which in turn meant re-attaching the suspension), I was able to do less that I would have liked.

Idle vibration

With the car running and the engine hatch open, it was possible to see the engine bouncing around from side to side. A check of the airflow into the carbs revealed that, at idle, the left-hand cylinders were doing almost nothing. The right-hand carb would not return to 'idle' -- stopped against the idle speed screw -- because the throttle linkage was too long.

Simple enough: just shorten the throttle linkage, and adjust the idle speed on both carbs to get the engine idling where it should, and with equal flow on each side.

The throttle linkage on these cars is a series of threaded rods with sockets on the ends; turn the sockets on the threads, and the length of the assembly changes.

Problem was, the linkage on the right side was too long because the threaded portion of one of the rods was bent. I straightened it a bit, and attempted to force the socket further onto the rod. After about a quarter turn, the threaded rod snapped. Sigh.

So now I'm left with this rod (in two pieces), and two sockets -- one of which has left-handed threads. (One end of the rod and one of the sockets have normal threads; the other end and socket have backwards threads. The point is that you can easily adjust the length of the linkage by just turning the rod.)

Fortunately, I have an extensive collection of spare Porsche parts (which does not include the broken rod in question, of course), as well as a lot of old junk that Nicole is constantly telling me to throw out. I assembled two normally-threaded linkage sockets and a length of rod stock that used to be part of an Ikea shelf cross-brace. I also found and dusted off the Sears metric tap and die set. Ta-daaaaa. Cut the rod to length, put threads on both ends, screw on the sockets, and hey presto, I have new throttle linkage. I also made a locking nut out of some flat 1/2" aluminum stock I had laying around, but I'd rather not talk about that.

The Ikea linkage is intended to be temporary, only in place until I can get a replacement. Of course, the part seems to be totally unavailable, and left-handed dies are only a bit less rare. I might wind up just making a slightly (very slightly) nicer version out of proper rod stock and leaving it at that.

Sloppy Shifting

Judging from the number of replacement shifter products available, I'm not the only person dissatisfied with this particular aspect of the Porsche Experience.

The Porsche 5-speed transmission of this era has a shift pattern you don't ordinarily find on road cars. First gear is to the left and backward, with reverse 'above' it, i.e. to the left and forward.

There is a spring-loaded doohickey that, in theory, prevents you inadvertently shifting into either first or reverse gear. To put the car in first, you pull the lever to the left until resistance is felt, then you pull it toward the left some more (compressing the springs), and then toward the rear of the car. To put it in reverse is the same procedure, except toward the front.

So, every time you start the car from a standstill, you put wear on the previously-mentioned bearing surface on the spring-loaded plate. Over time and miles, the shift lever wears the bearing surface down until the spring-loaded whatsit doesn't really do anything, because there's enough clearance for the lever to more into the reverse or first gear positions without any of that business with the springs.

And, of course, the spring plate that wears away is not available. It was only used on thousands of cars over a period of about ten years. You definitely wouldn't need to make replacements for that kind of niche part.

I wound up thoroughly cleaning and re-greasing the spare shifter assembly, and installing that. The replacement had some wear on it, but nothing like the one I took out of there. I suppose I'll wind up having to weld together a replacement spring plate. I'm not sure how much longer until the wear again gets bad enough to be unusable.

The other problems are on hold for right now. After bolting the suspension back on the white car and attacking these make-your-own-parts projects, I was not equal to screwing around with the other things. It's raining this week, so I'm not driving the car anyway. The next "major" challenge to be met is raising the front of the car back to where it ought to be. It seems to be pretty straightforward, but I've learned to be wary of that.