Distributor Timing

Many of you have heard one of my favorite expressions “Timing, … timing is everything!” Well, this month that’s just what I want to talk about. And, maybe a few things more. How many of you BJ8 owners have rebuilt your engine? A few probably. When you put the distributor back in after the rebuild, did you have problem with the vacuum advance unit interfering with the oil filter? I’ll bet you did if you followed the shop manual and had your number one spark plug wire in the “three o’clock position” where the rotor points to the locator notch and where the hold-down clamp attaches. To the best of my knowledge (and I could be wrong on this), all 6 cylinder cars originally had their distributor caps wired with number one in the position I’ve described above. But for more clarity, I call 12 o’clock the orientation of the cap such that the spark plug wires point directly to the imaginary 12 on the clock as you are looking down on the cap (caps don’t get no respect anyway!).

The shop manual, written long before the BJ8 engine and distributor came along, tells you to install the driving spindle (the slotted, geared thing you stuff into the distributor hole that the distributor then mates to) in the “twenty-to-two” position. This kind of tribal mating ritual works just fine for all 6 cylinder cars with a mechanical tach where the tach dive mechanism placed between the driving spindle and the distributor. For, you see, it places the distributor well above the oil filter with adequate clearance for the vacuum advance unit. Ah, not so BJ8s with their electronic tach, and a different distributor that mates to the engine much further down into the “dark pit”. If you use the “twenty-to-two” technique, you will have problems timing the engine unless you, 1.) alter the wires coming from the distributor or, 2.) re-install the driving spindle in a different position. “What position is that?” you ask? I, too, asked that question. Here’s what I got for an answer!

Having placed the drive spindle in the appropriate position in the engine (and car) I’m reassembling, such that the distributor’s vacuum advance unit would nestle neatly between the engine block and the oil filter, leaving enough room to accurately time the thing, I asked several (two, actually) innocent bystanders (I had to go get them) to describe what they saw in looking down into the drive spindle hole. Having gotten several off-the-wall comments, I told them to just describe the slot in the drive spindle in terms of the hands of a clock. Here’s the results! My son said it was “four fifty-five or eleven twenty-five”. My wife said it was “twenty-five-after-eleven”. Well, I guess opposites attract as I said it looked like “five-to-five” to me! Isn’t diversity of opinion wonderful?

Here’s the picture of the drive spindle. Pick your favorite “time” from the observations above for your BJ8 and install the drive spindle as I have marked and you will have no problem with clearance (unless you are one tooth off!) I’ve about run out of time for this subject, so follow your shop manual for the rest of it. It won’t lead you too far astray. But remember the “twenty-to-two” rule for mechanical tach drive style distributor mounts and “five-to-five” rule for BJ8s. Hope this has been a timely tip!


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