Wipers - Changing park position

"While you are in there" doing something in the luggage compartment that involves removing the fresh air intake duct/hoses/fan/stuff, it's a good time to change the wiper park position from the left to the right, if that strikes your fancy (it gives you a clearer view of the front fenders, kinda reminds me of a big pair of ...cruise missiles...see how I cleaned up my politically incorrect thoughts). Some 911s came from the factory with wipers parked on the right.

To start with, remove the fiberboard cover inside the boot that covers the front of the dash.  Next remove the fresh air intake grille in front of the windshield.  This provides access to the Phillips-head screws that retain the plastic fresh air duct.  Remove them, along with the one small screw that locates the plastic duct to the metal floor of the boot.  Then disconnect the paper hoses from the duct.  Push the hoses gently aside.  It is not necessary to disconnect the linkage control wires.  Rock the plastic duct back and forth to break the gasket seal, and swing it aside.

When you have all of the "stuff" removed or pushed aside, you can see the wiper motor.  Remove the nut from the end of the wiper motor shaft, and gently pry off the short section of the wiper linkage.  Wet the windshield to prevent scratching, rotate the linkage 180 degrees (the wipers will move to the passenger's side of the windshield), and reattach.   Actuate the wipers to test that they park where you want. Adjust as necessary, retest, and tighten the nut.  Be careful not to overtighten--you can damage the motor.  Reinstall all the stuff.  Be careful to reattach the drain hose at the bottom of the plastic duct.

To complete the wiper park position change, modify the wiper arms.Remove the "bent" arm, place its U-shaped end in a vice, and bend it to the corresponding opposite angle.  It takes a little effort, but the wiper arms are suprisingly malleable.  Then just transpose the left and right arms.

Bob Tindel


Warm Up Regulator - Making adjustable

The article on making the WUR adjustable is by Jay Pineau, Ark-La-Tex Region, PCA,  in Volume VII, pages 116-117 of Up-Fixin.  In case you don't have that, here is the text:

"An engine equipped witha Bosch CIS (K-Jetronic) fuel injection system depends on the accuracy of the control pressure for starting and drivability performance.  If during a system pressure and performance test it is determined that the warm-up regulator is at fault, you are faced with an alternative: replace it (list price now about $280) or attempt to repair it.

The regulator is a fairly simple device which varies the control pressure with temperature (both engine and self-induced via an internal heating element).  There are two main causes of malfunction: heating element failure and foreign material in the metering chamber.

A quick check with an ohm meter will determine if the heating element is defective.  It should read 18 to 22 ohms resistance (I didn't get this exact reading, but it wasn't an open circuit).  If the element is faulty, the regulator must be replaced unless you can locate a replacement heating element from a used regulator.

If satisfactory, the regulator can be carefully disassembled and cleaned.  Take care that the two small orifices are completely clear. If the diaphragm shows any wear, flip it over at reassembly.  (Be careful here--the diaphragm is VERY thin metal.  I didn't disassemble the bimetal spring, just pushed it aside to remove the diaphragm.)

After reinstallation, it may (WILL) require readjustment to obtain correct pressure relationships.  (These pressures vary with the year of the car and the part number of the WUR.  You can find them in the shop manual.  If you don't have them, I can xerox and snail-mail)

Bruce Anderson described in PANORAMA (October 1984) how this adjustment can be accomplished by "knocking the plug".  The only problem with this procedure is if you "knock" it in too far, you must remove and reassemble the regulator to "knock" it back (indeed true, I tried this method).  By the time you have obtained the best cold and hot values, you may have to do it several times.

The unit can be modified to provide for external adjustments by the addition of a pull-out screw and nut which permits very accurate movement of the plug."

The article also includes a diagram, but essentially you drill and tap a 5mm hole about 10mm deep into the center of the plug. Then drill a second 1.5mm hole in the crack between the plug and the WUR body.  Put a 1.5mm roll pin in this hole and tap it down flush with the body (the idea is to keep the plug from rotating when you move it up and down with the pull-out screw).

Put a 5mm allen-head screw, with a washer slightly larger than the plug, and a 8mm diameter nut, into the 5mm hole.  Keep the nut backed off, and gently tighten the screw until it bottoms in the hole.  Now, to raise the plug (higher control pressure), hold the screw with an allen key and tighten the nut (it's a tight fit, but an 8mm box-end wrench should fit over the head of the screw).  To lower the plug (lower control pressure), hold the screw, back the nut off, and then tap the screw (I use a brass drift and it takes a fairly hard whack).

Of course, while you are doing any adjustments, you need to be looking at the control pressure.  I bought a CIS gauge from J.C. Whitney for less than $60.  Be sure that the electrical connector to the WUR is disconnected when setting cold control pressure, and that the engine is dead cold.  To get the fuel pump to run, jump terminals 30 and 87a on the fuel pump relay socket (on my 83, it is the red relay in the luggage compartment).

If your car doesn't have an O2 sensor, you are completely dependent on correct fuel pressures and mixture setting to get the engine to run correctly, so the WUR is important.  After I did the WUR modification, I am confident that I can set my engine up properly, and it starts and runs perfectly, cold or hot.

I hope this helps--if you want the diagram of the modification, send me an SASE at 30822 Alta Mira Drive, Redlands, CA 92373.

Bob Tindel


Warm Start Problem - 911SC

When I first got my SC, it was very difficult to restart after it sat for 30 minutes or so.  Turned out it was the fuel accumulator, which holds system pressure after the engine has been started.  You can check this out with a CIS pressure gauge.

This problem can also be caused by a defective fuel pump check valve.Even if you have the pump with the integral check valve, and it is defective, you don't have to replace the whole pump--just add a separate check valve in front of the defective one. The separate check valve is a Porsche part.  For the 80-83, the part number is 893 906 093 (M12x1.5--M12x1.5).  For the 84-89, it is 944 608 951 00)  M10x1.0--M12x1.5).  About $15 from Stoddard, 800-342-1414, or your local dealer.

Bob Tindel

The first item to check is the fuel pump check valve. This is a fairly easy job to do, just make sure you disconnect the battery before you do anything.  The fuel pump is behind a cover between the front wheels.  Remove the cover (I think its two 15mm bolts and two 8mm socket head bolts), use a small "C" clamp to  clamp off the input side
of the fuel pump.  The input side is a short piece of flex hose that attaches to the bottom of the fuel pump with a push-on type fitting with a hose clamp.  Remove the input side, make sure you have a container to catch any spilling fuel from the pump.  You'll need some metric ignition spanners to get the wiring connectors off, I think they are 6mm and 8mm.

Once you remove those (you'll probably have to loosen the strap that holds the pump so you can rotate it and get access) you'll have access to the output (pressure) side of the pump.  I think you'll need a 17mm and a 15mm spanner (itís a 19mm and a 17mm. I replaced my check-valve last weekend...terry)  to get this off.  There are several bits that fit together here.  Roughly, the check valve is a threaded tube with a nut shaped piece in the middle.  It threads into the top of the fuel pump.  The fuel line ends in a banjo style fitting, it slips over the other end of the check valve.  Then a large cap nut screw onto the other end of the check valve clamping the banjo fitting and sealing it.

Be aware there are two different kinds of check valves.  one is the "barrel" type that screws into the pump that I described.  I think this was used from '78 on.  Earlier cars used a check valve that was built into the banjo fitting. 

If you go to the porsche dealer they will try and  sell you the entire fuel pump, not just the check valve.

I really recommend getting the pressure tester and checking things out by yourself.  You'll also want the probst book on bosch fuel injection too.

Without doing proper pressure tests you won't know until you're done whether this is the fix.  It could be a fuel accumulator for example.

This is mounted in the engine compartment next to the fuel filter (more towards the front of the car).  If you have the old style it has two fuel fittings on top and a screw in the bottom.  You can check an old style by simply removing the screw.  If fuel comes out its bad.  Later ones had a fuel line in the bottom too.  You need the gauge tester to check these out.

( You can buy an inexpensive CIS test kit from JC Whitney (312) 431-6102.  It costs $54.95 plus s/h.  Part No. 12BH3617U.  Kit includes pressure gauge, hoses, valve and adapters.  For the money it's not a bad buy considering the one from Bosch is around $700.00.  Other than the gauge itself being a little on the cheap side, it's an okay unit.....terry)

Martin Walker


Window Regulator - Repair

Recently, while installing new speakers in the doors of my 1983 911SC, I found a loose part in the bottom of the door.  I took it to my favorite wrench, who identified it as part of the window regulator.  Some months earlier, I had heard a popping noise in that door, but the window continued to work fine.  Window regulators sell for $200 and upward, but they often can be repaired economically.  This procedure describes repair of an electric window regulator, but manual regulators are similar.

The first step in repairing or replacing the window regulator is to remove the door panel.  That is covered in a separate item on this site.

After the door panel is removed:

1.  Lower the window slightly more than halfway, and tape it in position.
2.  Remove the two allen-head screws holding the rear end of the regulator, and the four allen-head screws holding the other end, where the motor and gear mechanism is located.
3.  Detach the two wires from the motor, noting which is connected to which terminal, and how the wiring is routed through the motor bracket.
4.  Manipulate the entire regulator/motor mechanism to remove the white plastic rollers from the tracks attached to the bottom of the window.  (It may be necessary to move the window up or down to do this.)
5.  Unbolt the motor from the regulator by removing three 10mm cap screws, and remove it from the door.
6.  Remove the regulator from the door.  This may take a little fidgeting, as it is a tight fit, but it will come out without forcing.
7.  The regulator and motor can now be inspected and tested.  In my case, the loose part was the anchor stud for the regulator spring.  It is merely swaged into place, and it can be reattached easily by peening.
8.  When the regulator is reassembled with the spring properly tensioned, it will be roughly L-shaped (impossible to put back inside the door without removing the window channel).  Pull the spring-loaded arm down until it is aligned with the rest of the mechanism, and tie it in that position with a cable tie.  Test fit the motor to ensure that it aligns with the mounting bolt holes and the regulator gear teeth.
9.  The regulator can now be inserted into the door (without removing the window channel or glass).
10.  Bolt the motor onto the regulator.  After ensuring that the gears mesh, cut the cable tie.
11.  Reinsert the rollers into the window track.
12.  Reinstall the allen-head screws and reattach the motor wiring.
13.  Test operation and reinstall the door panel.

Bob Tindel
83SC Guards Red