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BJ8: 650 RPM steady Idle at 45 Degree advance???

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Assuming the 45 degrees referred to above is at maximum advance (3000 rpm or so).

Pulley distances for maximum advances:
Pulley Diameter (D) = 6.25"
Circumference (pi*D) = 19.625"
With pulley notch at pointer, 32 degrees BTDC = 1.75" to right of notch as viewed from front
35 degrees = 1.91" to right of notch
45 degrees = 2.45" to right of notch
 
RAC68 said:
Hi All,

As far as I am aware, the notch is located on the inside edge of the pulley which is keyed to the crankcase. If the damper has broken loose and moved, it should not affect the position of the pulley. I also looked at my BJ8P1 damper and could not tell, but don't believe my damper was integrated. However, my reading of the Moss description for the integrated damper and pulley is that models prior to the designated BJ& forward were different from former BJ8s and models. As such, and since separate dampers are no longer available, they suggest everyone install the integrated version. However, integrated or not, I would expect the pulley would be still anchored to the crank with a key and the damper vulcanized to the pulley. If the damper moves, on either model, integrated or non, there should be no movement in the pulley or TDC notch.

Greg may be correct that my adjustable timing light may be having difficulty with the Pertronix and high powered coil. I don't think this is the case as I have checked my BJ8 (Crane Electronic Ignition, 40KV Pertronix Coil) and registered a steady 15 degrees without vacuum advance and could easily see the effect of both distributor and vacuum advances.

Until I do get a chance to tactfully check to make sure the mark I used was correct and not another notch placed for another previous reason, I tend to believe this is the case.

Again, thanks all,
Ray (64B J8P1)
Click to expand...

This weekend a friend was discussing this and said this could happen if the distributor driving gear was one or two teeth off.
 
steveg said:
This weekend a friend was discussing this and said this could happen if the distributor driving gear was one or two teeth off.
Click to expand...
Probably true. Easy to check. Clip the timing lite sparkplug attachment on each of the wires...#2, #3, etc., etc. I had mine 180 degrees out and I was able to time my car by attaching my timing lite clip to #6 plug wire. I since corrected that.
 
The distributor drive dog on a BJ8 is either in the right position or the wrong position (180 degrees out) as it has a key cut end. The earlier Healeys have a drive dog with multiple teeth which can be one or two teeth out but not the BJ8.. You need to look elsewhere..
 
British_Recovery said:
Maybe the gear that the drive dog goes into is in the wrong position. Since it is angled, as it goes in, it will rotate.
Bob
Click to expand...

The distributor rotates at 1/2 engine speed, therefore 45 degrees on the crank = 22.5 degrees on the distributor. 360 / 22.5 = 16. If the drive gear has 16 teeth, that would be 1 tooth off.
The gear would need to be retarded (rotated counter-clockwise) 1 tooth.
 
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