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Switching from points to electronic distributor module on my 1971 GT6

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Tonyfixit Avatar
Tonyfixit Tony M
Duncan, BC, Canada   CAN
I don't think it is the up and down movment of the shaft that is the problem. It is any side to side motion that will effect when the cam opens or closes the points.

On my worn distributor the points could be either open or closed depending on just how the shaft might wobble.

A new bushing in the distributor did not completely cure the problem because there was wear in the shaft aswell as the bushing.

Longer bushings that extended beyond the shaft's wear area fixed the problem, along with an EI conversion that does not rely on a cam pushing points to deliver accurate ignition.

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spitfire50 Avatar
spitfire50 Paul Mugford
Rochester, N.H., USA   USA
In reply to # 1490822 by Tonyfixit I don't think it is the up and down movment of the shaft that is the problem. It is any side to side motion that will effect when the cam opens or closes the points.

On my worn distributor the points could be either open or closed depending on just how the shaft might wobble.

A new bushing in the distributor did not completely cure the problem because there was wear in the shaft aswell as the bushing.

Longer bushings that extended beyond the shaft's wear area fixed the problem, along with an EI conversion that does not rely on a cam pushing points to deliver accurate ignition.

Tony,
The up and down motion could certainly throw the timing off. As the shaft moves up or down the drive gear may also follow it some. As the gear teeth move up and down they also change the timing because of the helical cut of the gear. Just like the gear turns a bit as you drop it into engagement with the cam. Luckily the gear is trapped between the base of the dizzy and the drive gear bushing pressed into the block. So it is only excess clearance that allows the gear to move up and down with the dizzy shaft. If assembled within spec there is only 0.003"-0.007" of end play for the gear.
All the best,
Paul

Tonyfixit Avatar
Tonyfixit Tony M
Duncan, BC, Canada   CAN
To move up and down 1/2" I suspect the top part of the shaft was being pulled up against the centrifugal advance springs.
I can't imagine the drive gear allowing that much movment.

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spitfire50 Avatar
spitfire50 Paul Mugford
Rochester, N.H., USA   USA
Tony,
The drive dog would be falling off the shaft if the main dizzy shaft could move 1/2". You're right the upper shaft/points cam must have been sliding on the lower shaft. The rotor would stop that motion when things were together.
I just checked a fully assembled spare Delco dizzy. The lower shaft moves about 1/16" from lowest to highest positions.
All the best,
Paul

agoodcave Avatar
agoodcave Mike Cave
Oceanside, SoCal, USA   USA
Martin,
Once you go electronic, you'll never go back. That rebuilt distributor will just sit on the shelf as an OrEM novelty.

Mike

arturo64 Avatar
arturo64 Arthur T
Billings, MT, USA   USA
Martin. Thanks a ton for that write up. That helps a ton as I have some of those symptoms as well. I actually have more of those symptoms in my dang Amazon.



Arthur
68 spit
70 gt6+

1Gapex Avatar
1Gapex Albert C
Huntingdon, QC, Canada   CAN
Hi Martin, as i a am also having similar issues:
Sputter between 1800 to 2400 rpm during a load/accel. If I gently roll on throttle or hiway cruise with no big power demand there is no issue.

As I was reading your posts I wanted to ask if you are using the same coil for your new distributor as your point distributor? I wonder if there would be any resistance differences due to lack of points.

I too have the big 1/2 inch(approx) up down play on distributor shaft. So I will go in to it further in that sense

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Tonyfixit Avatar
Tonyfixit Tony M
Duncan, BC, Canada   CAN
In reply to # 1540110 by 1Gapex
I too have the big 1/2 inch(approx) up down play on distributor shaft. So I will go in to it further in that sense


Read posts #18 and #19

Triumph Guy Steve Shackleford
Meridian, ID, USA   USA
Martin,
For future reference,you can always do a search for instructions online. I found this:

http://www.accuspark.co.uk/fitting_guide.html

Go there and hit print and you'll have it again.

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