And is this something I can find at my local part store? Or something I'd have to order? I need one to set the MCS on my LG4.

Thanks,
Matt

 

its the actual measure in crankshaft degrees that the points (as in ignition points that were used in pre 74days befor hei) are closed to charge the coil.
If a multitester has a tach setting, it normally has a dwell.

 

Should I be able to find one at a parts store? Or is it some type of special order thing? I can't seem to find one at any online places. I was just looking around trying to see what it is.

Matt

 

Here is onehttp://www.sears.com/sr/product/summ...id=00921016000

 

Golden,

A "dwell" meter is basically a duty cycle meter that is graduated on degrees of distributor rotation for an engine. In Kettering (breaker point) ignition system terms, the duty cycle is the amount of time that the circuit is on (points closed) versus the amount of time the circuit is off (points open). The meter face is graduated in degrees of distributor rotation. A point dwell angle of 30° on a V-8 engine is basically a 66% duty cycle, or ON time versus OFF time. One cylinder fires every 45° of distributor rotation (90° of crank rotation), so if the points are closed for 30° of that time, they are open for 15° of that interval. 30° ÷ 45° = 2/3, or 66%.

A six cylinder engine is similar, but one cylinder fires every 60° of distributor rotation (120° of crank rotation). Typical specs for ignition point dwell on a six cylinder are 33°, and on a four cylinder engine 40° is common.



In terms of the mixture control solenoid on your carburetor, it is basically the same thing. The dwell meter is used to determine the amount of time the MC solenoid is ON versus OFF, or duty cycle. Since most automotive technicians have (or had) a dwell meter, the specification is presented in terms of dwell degrees. In reality, the measurement is the duty cycle percentage of the solenoid, but the common dwell meter is not graduated in those terms. Remember that 30° on the "V-8" setting on your dwell meter really means 66% duty cycle, and 45° would equal a 100% duty cycle.

Typical instructions for setting the solenoid are to set the meter on the six cylinder scale and adjust the "dwell" to an optimum of 30°, or in reality a 50% duty cycle. This means the solenoid is ON an equal amount of time that it is OFF. This is the optimum setting for fullest range of control by the MC solenoid.

If you don't have a dwell meter, but do have an oscilloscope or better quality DMM with a duty cycle scale, just set the MC solenoid for 50% or as closely as you can get it. The typical instructions indicate that any reading between 10° and 50° and varying is acceptable (15-85% duty cycle), but "acceptable" isn't good enough for most of us, or we wouldn't be here.

If you don't have either, I wouldn't waste money on a dwell meter, but would apply whatever money you would have spent toward a good quality DMM, like a Fluke 78 Series for about $200.

Fluke 78 Automotive Meter

BTW - This "file attachment" feature apparently isn't very reliable...