So, you believed the Maestro and bought a .050 Distributor to replace your worn out old one, eh? Good Show. Or maybe, the Rather Strange Behavior of the Xenon Flash Timing Light when attached to your Original Distributor bothered you! You know- that time you Waited 'till Dark so's you could see EVERY spark. And you hooked the Timing Light up, then fired the engine up, went back to the back, and marveled
at the "Corona Discharge" all around your spark plug wires (visible only on a Dark Night, with no moon and no flashlight,out in the Boonies, with a strange wind blowing. Remember THAT Time? Eerie!
Then, you shook off the spooks, grabbed your trusty strobe light, pointed it at the engine and pulled the trigger. So you could see where everything generally was FIRST, BEFORE the fan belt bit your hand off or grabbed (and destroyed) the Timing Light! As the High Energy Quanta from the Strobe illuminated the engine, you marveled as you saw the engine "jerk" around- just like those Old Time movies you saw as a
kid! On a 912 with the rubber baby buggies, and bad Solexes, this is the ONLY way you can SEE the engine when it's running! Otherwise, the 912 will vibrate too fast for the eye to see! (Heh, heh).
Or, WHAT'S THIS??? As you rev the engine up and down, the timing wanders around- WILDLY! Not in that smooth, continuous way it should!
Such can be the case with the Average 20-year Old Original Distributor! They're dying, fans- just like we will too, someday. So give the Original a rest- and buy a NEW Bosch .050 Distributor! Better yet, buy TWO of 'em. They're cheaper that way too, and you'll have Spare Parts. (Which means that ifin you have Spare Parts, the cap/points/capacitor/rotor will NEVER wear out. And you'll never drop the cap and break it either.) If you don't have spare parts, you WILL drop and break the cap! With TWO, you'll have spare parts. And TWO .050's will cost you LESS than ONE .031 Replacement Distributor.
The RIGHT way to go about changing a distributor is really very logical. FIRST, pop off the cap of the OLD, still installed distributor. Crank the engine over with a 30 mm socket wrench (or a large adjustable ifin you're a VW mechanic), or your hand, or a friend using the starter motor, (but not with a combination of the above), until you get to Top Dead Center on #1 cylinder.
Then, align the notch in the "OT" mark with the notch in the Third Piece of the Case, and glance at the distributor rotor. The rotor should be pointing to about "4 o'clock" Look directly DOWN on the rotor. Is the notch in the end of the rotor aligned with the notch in the BODY of the distributor? If it is, congratulations, you've found Top Dead Center on #1 cylinder, AND the distributor was installed correctly to boot. Check this conclusion by placing the cap on, and seeing if the rotor DOES, INDEED point to the #1 spark plug wire!
Now, disconnect the wire going to the distributor from the COIL. Then, loosen the 10 mm ATF (Across The Flat) nut in the distributor clamp, and pull the old distributor up and out.
Look down inside the hole whence came the distributor, and make sure that the little spring is in its proper place in the center of the Distributor Drive. It is? Good. If the little spring is NOT there, hop on down to your VW dealer and get a distributor drive spring before reinstalling the new .050 distributor.
OK, the spring is there like it should be. Great. Now grab the .050 distributor. Note that it does NOT have an Seal ring on its shaft! Use one of your left over Distributor Seals from a Lower End Gasket Set, or get one from a VW dealer, Though the distributor will usually NOT leak withOUT a gasket, it's still better to put a gasket on, although a New Distributor Gasket can make the installing the distributor a real chore, a new distributor gasket won't let oil mess up your nice clean engine compartment either!
With a new seal installed on the new .050 distributor, only heavy lubrication of the seal and hole will allow
successful insertion of the distributor's shaft into the nether regions of the case! As it is in other things, if she's dry, she can be difficult, But if she's Properly Lubricated, she can be VERY nice indeed!
HALT! Before you install the distributor into its hole, make note of the angle of the slot in the distributor drive shaft. Since your Pulley is still lined up at Top Dead Center on #1 Cylinder , the Distributor Drive slot should be "parallel" to the mating seam where the Third Piece of the case meets the Two main case halves! Also, the "slot" is a Chord" of a circle and therefore offset. The smaller section of area between the Chord" and the circumference should be towards the REAR of the car!
(NOTE: If the slot is NOT parallel to the mating seam, go get yourself a Distributor Drive Shaft Puller (a VW tool), remove the FUEL PUMP (and remove the fuel pump DRIVE ROD, ifin the Fuel Pump is an "A" or a "B" . C/912 fuel pumps fortuitously have the fuel pump drive rod as an integral part of the fuel pump, so you don't have to worry about the fuel pump drive rod ifin your fuel pump is a C/912 type!)
Then, remove the little spring in the center of the Distributor Drive, and install your VW Distributor Drive
Puller in the Distributor Drive. Tighten the puller up and pull the distributor shaft up and out far enough so the drive shaft clears the crank gears. (If you do this carefully, the thrust washer underneath the Distributor Drive may not fall out into the Third Piece of the Case!)
Then rotate the distributor drive shaft and push down carefully to re-install the Distributor Shaft! Is the slot
Parallel to the Mating Surface of the Third Piece of the Case? If yes- Good! If not, try again! Replace the little spring in the center of the Distributor Drive when you're done.
Be REAL careful- it's VERY easy to mistake which is the "narrower" half of the drive gear! Even the Maestro's muffed it once or twice.
Having installed the Distributor Drive Shaft Properly, insert the well-lubricated distributor. Rotate the rotor while pushing down on the distributor's body until you feel the tang mate with the slot. Ahhhhh, say the slot (and you) when this happens! Now, Relax.
Then, Rotate the distributor's body until the notch in the rotor is pointing to the notch in the BODY of the .050 distributor! That should be #1, as long as you haven't turned the engine over! Note that the rotor of the .050 distributor now does NOT point at 4 o'clock like the Original did!!! In fact, the rotor of the .050 now points at 7 o'clock!!! Relax - it's OK. No big deal. Note also that the CAPACITOR of the .050 Distributor actually CLEARS the Return Oil Line from the oil filter!!! Unlike the Capacitor of the .009 Distributor, which
INTERFERES there!
Now remove the rotor of the .050, take off the plastic water shield, and look at the points. Nice, huh? Rotate the body of the distributor until you can just see the points opening. Do this several times, trying to catch the exact point when the points just BEGIN to open! Got it? Put a little dab of Bosch Distributor Grease on the distributor cam, for Proper Lubrication.
Now, replace the rotor (withOUT the plastic water shield in place)l and look vertically downwards at the rotor. Does the rotor point towards the notch in the distributor body? It does? Good! Now, tighten the distributor clamp down, slowly and carefully- being careful not to move the distributor!
Attach the green wire from the .050 distributor to the spade terminal on the coil. (If you don't have a Spade
Terminal on your coil, get one - hopefully you read all this FIRST, so if you have an Old Original Coil with NO spade terminal, you got another one with Spade Terminals, or got just the Spade Terminal offa some coil in advance!
Remove the rotor once again, replace the distributor's plastic water shield, put the rotor back on, and replace the cap. Attach the spark plug wires - NOTING THAT on the .050 distributor, #1 is NOW AT 7 o'clock!!! The Firing Order (Clockwise from #1), is 1-4-3-2. That should help. Let's see that's the RIGHT FRONT (#1), the LEFT REAR (#4), the LEFT FRONT (#3) (We all know where THAT one and the RIGHT
REAR (P2).
OK, all set? Fire it up! It Runs? GREAT. (Ifin it DOESN'T run, go back and check the Spark Plug Wires with the Firing Order. That's usually where the problem lies!)
Now, shut it off, and get out your timing light. Attach the red wire off the timing light to the Hot lead of the coil (the left hand terminal (driver's side terminal, ifin you will), and the black wire of your timing light to a convenient ground. The metal fitting where the inlet oil filter line attaches to the oil filter usually works pretty well. Hook up the third wire of your timing light to the #1 spark plug wire - remembering that #1 is now at the 7 o'clock position!!!
Place the timing light and its wires out of the way of the fan belt. Fire the engine up. Point the timing light at the crank pulley and pull the trigger. Marvel at the correctness of your guesstimate timing! Adjust if necessary.
Now, rev up the engine to 3000+ RPM. Does the distributor give you almost EXACTLY 30 degrees Total Advance? It Does? How About That! Rev it up and down a few times, Marvel at the ROCK-STEADY SPARK ADVANCE!!! Marvel also at the LACK of the sudden "jerks" of the pulley. That's the Advantage of a New Distributor!
Shut the engine off, return to it and disconnect the Timing light, Take your baby for a ride. Doesn't it feel a lot better! Do you regret replacing the defunct Original now? I thought not! Have fun and:
KEEP THE 356 FAITH!!!
Maestro
