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Old 07-03-2020, 11:07 AM
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Dilbone Dilbone is offline
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Default Ignition Timing Trophy 4

I've had my 1962 for a couple years now and it has been running a little rough and a little warm lately. I decided it was past time to check the points and timing and get it running like it should.



I found the specs of .016" for the points gap and 6 deg BTDC on the timing easily enough but I couldn't for the life of me find any information about the 2 timing marks on the harmonic balancer. After searching and searching to no avail, I decided the one had to be TDC and the other had to be the 6 deg mark.

The point gap was .011" so I adjusted it to .016"
The timing was showing up at what I assumed was the TDC mark(the one on the bottom in the pic) so I adjusted it to the top line which again I assumed was 6degrees.

The idle picked up and it was running much smoother. Taking a test drive showed significantly more pep and the running temp was about 10degrees lower than it had been running. Finally.

After doing all of this yesterday I decided to do some checking myself on these marks. I measured the diameter of the harmonic balancer and divided the circumference by 360 degrees. I measured the gap between timing marks and found it to be 6.024 degrees according to my measurements and calculations. Just as I suspected.



I decided I would post this here since I hadn't been able to find this information through any of my searches.

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  #2  
Old 07-03-2020, 02:23 PM
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Bill Hanlon Bill Hanlon is offline
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Good math.

If you make the assumption that one of the marks is TDC then the one that is BTDC has to be the one that is clockwise when looking from in front of the car.

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  #3  
Old 07-03-2020, 03:09 PM
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mechanickeith mechanickeith is offline
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Yes, the first mark is 6* BTDC, 2nd mark is TDC. Also, in setting the point gap, do you have the small distributor cap or large one. Large Dist. you will need to set the dwell also.

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  #4  
Old 07-03-2020, 10:32 PM
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Dilbone Dilbone is offline
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Quote:
Originally Posted by mechanickeith View Post
Yes, the first mark is 6* BTDC, 2nd mark is TDC. Also, in setting the point gap, do you have the small distributor cap or large one. Large Dist. you will need to set the dwell also.
I don't know about the distributor or how to check/adjust the dwell

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Old 07-04-2020, 01:03 AM
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Quote:
Originally Posted by Dilbone View Post
I don't know about the distributor or how to check/adjust the dwell

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The small Dist. has just 4 plug wires coming off of it. The large dist. has 4 wires but there are 4 flat spots between the 4 wires. Much larger cap than the small one. On large Dist. you will need a dwell meter & a special tool to adjust the points. If you have a large Dist. you will have to recheck the timing after dwell is set. Changing the dwell affects timing, but timing doesn't affect dwell. Because this is half of a V8 4 cylinder, the dwell is double that of the V8. Dwell should be about 74 on the dwell meter.

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  #6  
Old 07-04-2020, 08:54 AM
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Dilbone Dilbone is offline
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Definitely the small distributor here then. Good, one less thing to have to adjust lol
Now to get my front wheel cylinder rebuild kits, shoes, and rear shocks ordered.
Always something.

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