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Fuel Pump Diaphragm Tool

September 27, 2010 | Troubleshooting & Repair | 2 Comments
By Ken Daugherty I am illustrating a tool to set the A/B fuel pump diaphragm in the neutral position and tool to set the diaphragm and to remove the little clip from the C/912 fuel pump. 'A-B spacer block' shows the small wooden block that depresses the pump lever. The block is approx. 1/4" x 3/4" x 1 1/4". 'A-B pump tool' shows the block, 2, 30mm bolts and huts and a standard fuel pump block off plate. 'A-B' tool' shows the pump diaphragm in the neutral position, ready for final assy of the cover. (the diaphragm is this picture is a used one for illustration purposes only) 'C-912 pump tool' the component parts. A piece of sheet metal, ~16 ga., 1" x 5 1/2", A piece of conduit, ~7/8" x 1 3/8" long and 4 bolts, 2, 45mm and 2, 75mm' and 2 hex nuts. 'C-912 clip tool' This holds the diaphragm in placed so the clip spring can be compressed and the clip removed. 'C-912 diaphragm set tool' To set the diaphragm in the neutral position so the top cover can be properly fi...

Problem Using a Pulse Type Electric Fuel Pump

September 27, 2010 | Troubleshooting & Repair | 0 Comments
By Cliff Murray If you are having engine popping problems in a car that has been modified to use an electric fuel pump exclusively (no mechanical pump), first try locating your pressure regulator close to the carbs, and if that does not work then change to a rotary vane type pump if you have been using a pulse type. Here's my story: After having no luck tuning my 1883 with Solexes bored to 44mm/35.5mm for street use, I switched to Weber 44IDFs. Better but not great and the inconsistency of operation continued. Repeated ignition diagnosis and parts swapping bore no solution. Every jet combo you can think of without any improvement. Popping from the carbs (lean) and popping from the exhaust (rich) could occur at any time but never during wide open throttle. Sometimes I made a change and the car would run well (success?) only to have it revert to popping again. During this ordeal I had a Pierburg 6 volt pump fail and that was replaced by the supplier by an Airtex 6 vo...

Gas Tank Flush and Clean

September 27, 2010 | Troubleshooting & Repair | 0 Comments
Compiled by Mike Simmons, contributors listed below   Q: How do you restore an old gas tank? The gas has been sitting for 10 years.... LeicaLarry wrote, I cleaned mine out by flushing it with water. You might try breaking up the varnish with gasoline first. I then used a coating for the tank, Stoddard has it, or check Hirsh in New Jersey, make sure the over flo tubes are clear, use a wire as these releave pressure from the tank. If you wish you can wire brush off the rust and paint the area with a decent protective paint. If there are holes, you can solder them, or tin the area. Make sure all the fumes are out before you apply any heat. Washing with a garden hose for an hour, and then using a shop vac in the blower position for another hour will dry it. Chris Lonie wrote, I cleaned mine with b-12 and then took it to a radiator shop for an acid flush. They wanted to puncture it to drain it and then reweld it. I said no way and just ...

Ethanol and Gas — Comments and Controversy

September 27, 2010 | Troubleshooting & Repair | 0 Comments
Edited by Barry Lee Brisco based on contributions by Rick Dill, Christian Gates, David Jones, Charles Navarro, and Eric Nichols In some parts of the country you are increasingly likely to have to run your 356 on gasoline with 10% added ethanol (E10) or as little as 5%. This is commonly known as "gasahol". (The up to 85% ethanol blend, E85, is uncommon and requires vehicles be specifically designed for that purpose. The few gas pumps offering this are prominently labeled.) It is reasonable to wonder if using this mixture in a 50-year old car that was not designed for it is going to cause problems. Leaving the political and energy cost/balance considerations aside, the comments below should help you make an informed decision. More water in your gas tank?: Unlike modern cars that get driven regularly, many 356 owners may not drive their car for months at a time. David Jones writes, "Ethanol and alcohol fuels are hygroscopic [water absorbing] which is good and bad. Water wil...

Leaded Gas, Additives, and Octane Numbers — What Does Your 356 Need?

September 27, 2010 | Troubleshooting & Repair | 0 Comments
By Steve Douglas, David Jones, Alan Klingen, and Pat Tobin Editor: "Back in the day", when our cars were new, all American gas was leaded, and the oil companies touted its benefits, such as reduced engine valve wear. Then we all woke up to the fact that lead was a toxic substance and one way to reduce human exposure was to get it out of gasoline! But don't our vintage engines still need leaded, high octane gasoline? In short: NO. Here's why. Steve Douglas, A coupe original owner: Lead will keep the valve seats from wearing out, but only on engines that don't have hardened seats. 356s have aluminum heads and so have steel seats that are already hardened. Old American engines with cast iron heads that did not have pressed in seats need lead to cushion the valves, keeping wear down. I don't think any 356 needs leaded gas nor any additive, just run the best grade of gas you can, adjust the valves regularly, keep the mixture a little rich and timing advance conservative....

No Need to Use Avgas or Race Gas in Your 356

September 27, 2010 | Troubleshooting & Repair | 0 Comments
  By David Jones Pump gas is more than adequate for our cars and 93 octane at the pump is around about what we used to buy as 100 octane back in "the day". It just don't have lead in it which is a good thing. Unfortunately it may have ethanol in it which is a bad thing. Race gas and aviation gas is  made from the same base stock which is known as an alkylate. Only refineries with what we call an alkylation plant can make it so it is somewhat specialized. The refinery I work in does not have one so we only make "motor gasoline" Avgas is made to very specific formula which must be tightly controlled to prevent airplanes from falling out of the sky. It has a low RVP to prevent it gassing off at altitude and little to no distillates so it does not oxidize quickly like 87 octane motor gasoline. This is required because it can often sit for relatively long periods of time in parked aircraft in large quantities and if you know an airplane owner he will tell you if you ask h...

Fuel Valve / Fuel Cock FAQ

September 27, 2010 | Troubleshooting & Repair | 0 Comments
Text and photos by Barry Lee Brisco   The fuel valve or fuel cock (also called a "petcock", shown at right in a 356A) is one of those 356 peculiarities that generates frequent questions from new owners. Not used to having a car that offers control over fuel flow from the driver's seat, they are often either baffled by it, ignore it, or may even decide to remove it! In fact, it is a useful device that serves multiple purposes, and it is worthwhile to take a moment and understand its function. While at first glance it may appear to be dangerously exposed, Bruce Baker notes that after 40 years of seeing a few hundred 356s get mangled in accidents, he cannot remember a single incident of a fuel-related fire or a leaking gas tank (read more about 356 fuel system safety issues). Q. Which position is "on" and which is "off"? Q. What do all those funny German names mean? Q. How do I use the "reserve" setting, and how much fuel is in "reserve"? Q. Why not just leave the fu...

Gas Smell Troubleshooting

September 27, 2010 | Troubleshooting & Repair | 0 Comments
By Geoff Fleming and Tony Ryan Where to look when you smell gas inside the car Geoff Fleming: You will have to do a once-over check of various areas. Start at the engine bay, since a gas leak there can result in catastrophe. Check carb floats and look for worn hoses ( especially the link behind the fan shroud that joins the metal lines.) and at the fuel pump. Another culprit, lurking just out of sight, is the rubber line from the body to the engine bay. It should be replaced every five or so years, as it becomes porous and causes fuel smells. Next, I would examine the fuel cock. These are outboard on the T-6 series, (1962-1965). You might have developed a slight leak at the sealing surfaces. Check the hose connections too. If really ambitious, or if the obvious suspects prove innocent, remove the tunnel covering and check that the flexible hose "elbow" on the fuel line hasn't given up the ghost. Likewise, a fuel tank can develop leaks along the seams. Maybe you...

Hand Throttle FAQ

September 26, 2010 | Troubleshooting & Repair | 2 Comments
Contributed by Various 356Talk Contributors   Hand throttle location in A coupes and cabs Arrow shows hand throttle location in T5 and T6 B coupes and cabs Arrow shows hand throttle location to the right of the ignition, in Speedsters, Ds, and T5 B Roadsters Arrow shows hand throttle location in T6 B "twin grill" Roadsters (photo courtesy of T6 Roadster owner Tom Farnam) View behind dash of A coupe showing hand throttle cable housing The 356 hand throttle was introduced with the A model in 1956, replacing the choke used in the pre-A cars. In coupes and cabriolets it is located between the tach and speedometer, while on Speedsters, Convertible Ds and Roadsters it is to the right of the ignition switch (which is to the right of the steeering wheel, opposite coupes and cabriolets). By modern standards, the hand throttle is an anachronism, and there are regular questions on 356Talk regarding it's origin and use. Here are answers to these questions: Q. Can ...

A Systematic Approach to Full Throttle

September 26, 2010 | Troubleshooting & Repair | 0 Comments
By Ab Tiedemann The ball sockets should be checked for wear before the task is started and all replaced if any clearance or binding is felt. There are 9-10 sockets to consider and .05-.1 mm clearance in all those places could amount to about 12-15 mm of arc at the accelerator pedal. They also need some lubrication. Graphite grease works well. There is a fundamental design dimension that should serve as the starting point and it should be preserved when you are finished. The center of the ball on the little bell crank that attaches to the fan housing and connects to the pull rod coming up from the bell crank at the transmission should be 50 mm from the vertical surface of the fan housing. This is the starting point. The geometry is illustrated in the 356 C Workshop Manual, p SF 26, Figure 8. With the pull rod free from the transmission bell crank and the push rods free of the carburetor connection, adjust the near vertical push rod that connects the aforemention...