dwell meter
- Thread starter billfish
- Start date
FlatheadTed
Well-known member
Disconnect the coil from 6 volts then connect it to a 12 volt battery one to the hot side then one to ground , battery start the car on 6 volt ,run the coil on 12 you should fit a ballast resister before the coil if it hasn't got one .Most cars into the 50s ran six volt coils any way and you may find a ballace there somewhere .set the dwell meter up as normal .take the the readings and adjust accordingly .
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George/Maine
Well-known member
Well I went out to look at mine and it has 4 cylinder and 8 and also 6 cylinder.
Has tech high and low and dwell.
I think I bought it when I had a 74 olds with window could adj when running the best use for it. Dwell meter was not used by many people in the old days.
If you leaned how to adjust points it worked well. The shops used dist. machines, you would have not seen to many when there was a gas station on every corner.
It makes no since to put lead to coil side and to grd.
If you put the lead on the points side that's how I think it was used. 50-50 chance.
You can switch to tech and see how it reads.
If you want my opinion you don't need it.
As far as being accurate there is so much slop in the gears and chains wear it don't mean ****.
Has tech high and low and dwell.
I think I bought it when I had a 74 olds with window could adj when running the best use for it. Dwell meter was not used by many people in the old days.
If you leaned how to adjust points it worked well. The shops used dist. machines, you would have not seen to many when there was a gas station on every corner.
It makes no since to put lead to coil side and to grd.
If you put the lead on the points side that's how I think it was used. 50-50 chance.
You can switch to tech and see how it reads.
If you want my opinion you don't need it.
As far as being accurate there is so much slop in the gears and chains wear it don't mean ****.
I stripped this from another site and it seems you'll need a three wire meter to do this:
There is a simple way to get the 12 volt meter to work on the 6 volt ignition system. It requires a battery from a motorcycle, dry cell from a light, whatever has 12 volts.
Connect the power wires from the tach/dwell to the 12 volt battery, then, add a ground wire from the 12 volt battery to the engine, and connect the sensor wire form the meter to the negative post on the coil. read dwell/rpms, set accordingly.
The power supply from the 12 volt battery will NOT interface/interfere with the 6 volt system. The ground wire from the 12 volt battery to the engine proper only completes the READ circuit on the meter, the two different voltage systems remain separated.
Dwell meter/tach reads correctly when connected in this method.
There is a simple way to get the 12 volt meter to work on the 6 volt ignition system. It requires a battery from a motorcycle, dry cell from a light, whatever has 12 volts.
Connect the power wires from the tach/dwell to the 12 volt battery, then, add a ground wire from the 12 volt battery to the engine, and connect the sensor wire form the meter to the negative post on the coil. read dwell/rpms, set accordingly.
The power supply from the 12 volt battery will NOT interface/interfere with the 6 volt system. The ground wire from the 12 volt battery to the engine proper only completes the READ circuit on the meter, the two different voltage systems remain separated.
Dwell meter/tach reads correctly when connected in this method.
rotorwrench
Well-known member
Most of the old 12-volt cars that used points had either a ballast resistor or a resistor wire to the pos side of the coil. This resistance drops the voltage to near 6-volts at the coil. When you connect up the the points side of the coil, the voltage is dropped thru the primary winding too. The dwell time is the amount of time the points stay closed so the capacitor can properly charge up. If you set a new set of points with a wire feeler gauge to the proper gap, the dwell meter will generally read right on the money. If it's not, then you likely have a bad meter. Most dwell meters have a cam rate setting switch to compensate for 4, 6, or 8 cylinder distributor breaker cams. If it doesn't, then it would be questionable how a person can use such a meter effectively and for what cam rate it is initially set up for.
If you have a ballast resistor for a 56 or later Ford car, you can power the ignition off of a 12-volt battery with the ballast in the power line. The ground side of the battery can be grounded to the car frame/engine to complete the circuit. Make sure and observe polarity of the coil and don't turn on the radio if it still works. This action won't affect any of the other circuits in the vehicle if they are not turned on and the starter circuit will work just fine. In other words, hot wire it.
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FlatheadTed
Well-known member
In your case swap the 12v coil voltage to a 6 volt source ,as my above post in revers