Dwell meter going haywire

[Mudviper]

I put new contacts in the CJ, have the gap set, but thought I would check the dwell since the distributor that is in the CJ I don't think is stock. I have a digital meter that has a dwell setting on it, but when I connected it up to the negative post of the coil and negative battery terminal the meter will keep a steady reading. It jumps all over the place. Does the same thing when I try and read RPM's under the RPM set. Anyone have any ideas why?

[scoutpilot]

Since you didn�t mention what voltage the Jeep�s system is I can only guess that the Jeep is six volts and the meter is for twelve. Or I could guess that the points are not tightly installed. Or I could guess that the shaft bushing is bad. Or I could guess that the advance weight springs are bad. Or you�ve got the wrong distributor. Or the batteries in the meter are bad. Or the meter itself is bad. Need more information and possibly photos.

[Mudviper]

Since you didn�t mention what voltage the Jeep�s system is I can only guess that the Jeep is six volts and the meter is for twelve. Or I could guess that the points are not tightly installed. Or I could guess that the shaft bushing is bad. Or I could guess that the advance weight springs are bad. Or you�ve got the wrong distributor. Or the batteries in the meter are bad. Or the meter itself is bad. Need more information and possibly photos.

Electrical system has been upgraded to a 12V system. It is running a IAT 4008 vacuum advanced distributor, but the system is not running the vacuum advanced. Has a brand new coil with internal resistor. I checked and verified that it is 3 ohms across the terminals of the coil. Installed a brand new set of points (CS725A part number) and gapped at .020.

What photos would you need?

[scoutpilot]

�It is running a IAT 4008 vacuum advanced distributor, but the system is not running the vacuum advanced.�

[size=12]The vacuum advance is NOT hooked up? If this is true, how does the timing advance as RPM is increased?[/size][/b]

[Mudviper]

�It is running a IAT 4008 vacuum advanced distributor, but the system is not running the vacuum advanced.�

[size=12]The vacuum advance is NOT hooked up? If this is true, how does the timing advance as RPM is increased?[/size][/b]

Don't have a good answer for  you on that question other than that is how it was set up when I bought the jeep..lol. I don't know much about these engine operation, but it seems to run ok. I am looking to replace the IAT distributor for an IAD or IAY so I can go to a solid state and get rid of the points

[scoutpilot]

[size=12]Why don�t you just hook up the vacuum advance and see what happens? Be sure to carry a set of points and condenser for that time when the electronic part goes toes up. Those electronic ignition modules are very voltage sensitive. Feed it some sour power and it will assume room temperature.[/size][/b]