12 V dwell meter, 6 V car

Edwardjohnsr
Edwardjohnsr Expert Adviser
edited November -1 in HUDSON
I have a12 volt dwell meter and a 6 volt Hudson. I get a very low dwell reading (12-15). Could it be the meter? Should I double the meter reading to adjust for the lower 6 volt system? If I reduce the point gap to try to increase the dwell the car runs very rough or not at all. Any help form someone who understands dwell meters would be much appreciated.

Ed

Comments

  • Unknown
    Unknown
    Dwell meters come in analog and digital variants, both have circuits which are designed to correctly display the dwell for specified numbers of engine cylinders. The number of cylinders selected on the meter must match the engine being tested. In your case 6.



    Analog dwell meters usually work fine on either voltage 6V or 12V. Make sure that the + connection is on the + connection of the coil and the negative on negative. Digital meters may not work on both voltages. Often, a dwell meter is contained in the same cases a tachometer. Usually, these are hand-held units called “tach-dwell meters.” The dwell meter is used mainly for measuring the angle through which the ignition distributor shaft turns while the breaker points are closed. This is known as point dwell, or cam angle. Since the cam angle relates to opening and closing of the breaker points, adjusting the point gap also adjusts the cam angle. After making the point gap setting, it can be checked for accuracy (and readjusted if necessary) by hooking up the dwell meter and measuring the cam angle.



    Using a metal feeler gauge has its inherent problems... not perpendicular to the points, points are not truly flat on either or both surfaces, and the mounting of the points is insecure allowing slight movements. All can dramatically change the point clearance and thus the dwell. Make sure that all of these items are checked and that the mechanical adjustment is true to the specifications.
  • Park_W
    Park_W Senior Contributor
    Ed, it sounds like you've got a dwell meter that has to be connected to a 12v supply to operate. I've got the same situation. I use an inexpensive 6v "lantern battery" and connect it in series with the car's battery to provide the needed 12v to the meter. Works fine. Connect + of the lantern battery to - of the car battery, then connect - of the meter to - of the lantern battery, and + of the meter to + of the car's battery.
  • Unknown
    Unknown
    If you have a battery start rideing lawn mower hook the dwell meter to its battery.
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