Re: 82 320i Distributor Qstn (archive)

Hi, me again..guess I missed the part about the distributor. Anyway, I assume the part you see moving is INSIDE the bottom of the distributor, as it should be! Yes, it should move with the use of a vacuum pump, but not very far, mebbe 10 deg. As for the tangs that don't touch, I believe you are referring to the pickup tangs for the transistor amplifier box . This controls the current to the coil, for proper spark. The tangs should NOT touch, but come very close. There is a torroidal coil of wire in a mandrel underneath the stationary tangs. All this is, is a small alternator that generates a small voltage the transistor amp (switching unit) can use in time for the fireing events. The signal actually turns the main drive transistors on and off causing the coil to generate that high voltage. (actually it does the voltage thing on the "turn-off" state) This is practically a fool-proof system with very low failure rates. They go bad with a "poof", though.

If spark is suspected, or the timing of it, you must separate the troubleshooting to those two categories. Do the spark first: check all the connections for clean and tight. Check the distributor for wear by trying to move the shaft back and forth against it's bearings. Note: a lot of wear is tolerable in these systems w/o pionts as long as the tangs don't touch. Check the plugs, wires, cap and rotor. Don't forget to clean the connections on the "ballast resistor". My experience with these cars is that if everything else checks out, it's probably the coil. A cheap and dirty fix to hang a new one and be sure. Do NOT use anything but one designed for a 320!

Timing is a different ball game, where you must have a timing light and have painted on a visible set of marks on the front pulley at top-dead-center for cyl #1. This is in relation to some reference mark on the engine so that you can see the timing move around as the engine runs. It is dangerous if you are not attuned to working on running engines. Also, there is an oval hole in the top rear of the engine at the joint with the bellhousing/tranny. One can shine the timing light in there and see the proper marks from the factory: A ball, a "Z" and a "OT". Sorry, I'm not clear on their meanings, I time my engines by ear and seat of the pants. I think the Z is top-dead center and OT is the mark for either 1700 rpm or 2100 depending on year. "help"!!!!! I'm getting in too deep..

Somewhere in here is a gem you can polish and get your Baby running right again, I hope.

Tom

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