I have a small block with an Accel Street Billet that keeps going thru caps.
Car will run fine with brand new cap for 500 miles and then car will not start. Turns over but no spark. I have been pulling off the cap and bending up the rotor tang which will work for a few more miles, then again no starting. Seems like the carbon ball in cap is taking a beating, all voltages at coil (12v) and connections are good. I replaced my coil, installed new cap and rotor and thought I had won. 600 miles and again same symptoms. Any ideas or help- thanks

Sounds like the cap is not on correctly but if it was happening to me, I would put it in the garage sale bin and put on an MSD ready to run.

Have you changed cap and rotor?

3 times

Sorry, Just thinking a little more. The only way a rotor cap can move up is by the distributor shaft being pushed up, thus the shaft is tied to the dist gear and that gear is forced up by the cam gear.

Can you move that shaft up and down in the dist? Pull on the rotor and see how much movement there is. Should not be a lot.

Where has this dist been? Always in this motor? Thinking along the lines of the dist gear end shims?

Is this an Accel HEI?

Thanks for the response there is no movement from the shaft and I have had this dist in car for 4 years. Just started these hard starts in the last 9 months. The Street billet is an electronic breakerless unit.

Only thing left in my mind is , that bronze button in the cap is spring loaded or at least mine was. Might take the coil pack out and look under the big felt or rubber insulator washer to see what is going on.
Spring too stiff? Supposed to have some give, as my dist that came with one of my ZZ motors.
Those bronze buttons have been known to break into .

I quit buying Accel stuff years ago for just the reason you describe. Left me stranded in the middle of nowhere. I saw this note on the distributor....
"Works best with coil with less than 0.7 ohms of primary resistance."
Might want to check that.

Is the "Accel" cap tan in color? And, does it have the GM window for point adjustment in it (YES, I know this is an electronic distributor, but Accel made a few different models of electronic, some with the window caps, a lot more with other cap types).

ALL Accel caps are derived from stock caps, some are GM, window and earlier types, a lot more are MOPAR. This opens you up to more cap flexibility, not just the tan Accel caps from speed shops, just have to take the cap in and match it up at the local auto parts store. the MOPAR caps were derived from 1960's thru early 1980's distributors.

Instaled a new coil according to Accel tech rep, he felt that the coil was failing. Did not clear up problem. Yes it is a tan cap but no GM window or spring loaded ball. Checked all spark plug wires and plug gaps, I am going to try to find another cap, good idea. Sounds like excessive voltage eating up the carbon ball on cap ?

Looks like the end. Replaced coil wire due to high resistance, figured this would cure. Not. Finally pulled dist out and found that oil has been migrating up (?) dist shaft and collecting under circuit board. Cleaned and replaced board and so far ,so good. Accel dist must be wearing out internally? I have new motor going in over the winter, gonna give MSD a try. Thanks for all the responses.

If the cap has aluminum posts then it will wear and is of garbage quality. You need the brass/copper post type cap.

I was having all kinds of issues with my Accel Breakerless dist. It was eating coils and eating up dist caps. I thought i had it fixed and went on a 100 mile road trip. Ran great. On the way back it went down. I pulled the dist and coil and sent it to Accel to be repaired. The Accel tech said I was running the wrong coil and asked if I had read the directions. I was using a 8140 coil and needed a 8145. Also he said the cap was cracked. I went and bought an AC Delco dist cap(bronze tips) quite a bit heavier than the aluminum junk ones. So open the box and look at them. Rotor button, changed it. He asked me what kind of set up I had. Engine, trans, rear, compression, cam lift, and then set my springs on the dist. I got it back and put it back in my car, runs fine. Of course now its cold and cant really run long distances and rainy. But the few quick trips I went on, it runs fine. I hope this may help you. If it goes down again, Im going to MSD setup.