The Stovebolt Site Forums The Shop Area The Electrical Bay basic terminology of parts.

i am used to and familiar with modern parts/terms such as alternator,distributor,cap,rotor etc.
referring to these old trucks what is a generator and how does it differ from an alternator? what are points in comparison to our modern cap/rotor/distributor setups?

Hy stovebolt409, A generator is a generator of direct current [D.C.] which is what vehicles use to function, an alternator is a generator of alternating current [A.C.] which is what your house runs on, in order to use it it your vehicle it must be changed back to D.C., this is accomplished by a process called rectification. Even with the rectification process alternators have the ability to produce more current [amps] than a generator, and they can produce current at idle r.p.m.s. Points are nothing more than a mechanical switch which is opened and closed by a multi lobed cam on the distributer shaft, 8 lobes for an 8 cylinder engine, 6 lobes for a 6 cylinder engine and so on, modern ignition systems use various devises to replace the mechanical switch [points] to accomplish the generation of the high tension spark, hope that helps.

Have a look at your other thread regarding terminology. Red58 and I have some info posted over there.

stovebolt409,

This is probably much more than you wanted to know about charging system differences between old and new but here goes anyhow!

You now know the generator produces DC voltage and the alternator produces 3 phase AC voltage that is rectified to DC, but another big difference between these two items is that fact that the generator produces its power in the armature and all this oink has to pass through the delicate brushes to reach your system. The alternator produces its power in the stator, which as the name implies, is stationary...no funky brushes to deal with. This allows the alternator to be beefed up to supply ferocious amounts of amperage. The only brushes in a alternator are to supply a small amount of voltage to excite the rotor which regulates the charging process. Sort of bass-ackwards to the old generator. Now you know all there is to know...take a break!

Stuart