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Twenty to two

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Steve Huneck

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I have been working on and replacing the distributor on my BJ7 for the past couple of weeks, and there is something that has been nagging at me that I am hoping someone can help me with. In an attempt to keep everything simple when removing the distributor, I have been lining up the timing pointer and mark on the pulley while the rotor is pointing at the number one cylinder contact. When I look into the tachometer housing I see the driving spindle oriented in a "ten to four" position. It is my understanding that it should be in a "twenty to two" position. Could it be that the "twenty to two" refers to the drive dog which would be 90 degrees different? But then when would I ever see the drive dog as it is attached to the distributor spindle? The car runs, but I would like to make sense of the whole thing.
Thanks,

Steve
 
Hi Steve,
The twenty to two <span style="font-style: italic">mostly</span> applies to the side entry rotor cap of the original dizzy. It is to align the cap so the wires will reach their correct plugs. My car doesn't have the tach housing, I was able to pull the gear that engages the camshaft, rotate, then reinsert it to the correct orientation. This procedure should be similar with your tach drive though.
 
That does make sense. Right now when my rotor is pointing at the number one distributor contact it is also pointing at the number six cylinder (spark plug). A 90 degree clockwise rotation would move the contacts closer to the cylinder. I am in the process of switching to a top entry distributor cap and the wires I ordered do not reach. I cannot get the shortest wires to reach the 3 and 4 plugs anyway, so I will have to decide whether it is worth the effort to rotate the drive gear.

Thanks,

Steve
 
Yes it is worth it to rotare the drive gear and is simple eo do as stated in the shop manual.
 
as per the other topic;

"Where is the slot in the cam drive gear when you are on time and rotor pointing to #1 10 to 4 or 20 to 2--Like hands on the clock????"

It is at 10 to 4. Please bear with me on a small detail. I keep hearing, as well as reading in my shop manual, a reference to the position of the "slot". On my car the slot is on the drive dog attached to the distributor spindle. When I peer into the tach housing I see a tab that I believe belongs to the driving spindle extension. So, I think that if I remove the tach housing I should see the famous slot. As per the shop manual, I can then thread a 5/16 bolt into the driving spindle, pull it out, rotate it, and re-insert. Does that sound about right?
 
Figure B 4 (on page b4) in the manual shows what it should look like under the tach drive. One thing to note, the slot has an offset so the tach will fit only one way and might be 180° off. That is covered in the 1st paragraph on page B6. When you pull the gear up with the bolt, it will swivel up. So it can get mildly tricky figuring out how many teeth to rotate the gear.
 
Yes that is so Greg, However if he has the slot at 20 to 2 and the thin part of the off set faces the engine block he will be OK as far as the drive gear is concerned.
 
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