There is the roll pin, lower and upper bushings, the mechanical advance bushings and springs, the HEI module, the rotor, the vacuum advance diaphragm, the distributor cap and coil worn out.
TIP: Like with starter motors and alternators, I've seen a lot of garbage grade distributors pose as being "rebuilt". Advance curves so absurd they set me on the floor hysterical with laughter. THOSE REBUILDERS DO NOT USE A DISTRIBUTOR MACHINE to verify advance curves.
In a motorhome, a distributor with a laugh-a-minute pair of advance curves can eat a thousand dollars worth of gasoline or punch holes in your pistons so fast it'd make you sick. The last rebuilt HEI I checked had 48 degrees advance which has to be added onto initial (distributor twisting) advance. Garbage rebuilding.
A GM dealer used to offer reman distributors that like their alternators and starters, were rebuilt correctly. You might have a decent chance of getting a decent reman at NAPA. Most of the garbage remans used silicone grease heatsink compound beneath the HEI module. White Zinc Oxide must be used.
Yep, full agreement with the above posts. You is driving a time-bomb.
