alright here is whats going on. for some reason the ignition module is going bad everytime i put a new one in. This last time i went ahead and got new wires, cap, a rotor, and plugs. still blowing the module. any ideas as to why it is doing this? (the coil was replaced last night fyi)
I am not a pro at this, but I would guess either over-current or over-voltage. For the current side ... There could be some improper wiring relating to the ignition switch and the start & run system. Could it be that something else is wired in series with the ignition module and is drawing too much current through it? Or maybe the module doesn't have sufficient grounding, and the high resistance is causing an overcurrent condition? For the voltage side ... you might have a bad voltage regulator, letting the alternator put out too much voltage, or too much variation in voltage. Here are some suggestions (along those same lines) from the Wells Mfg. tech newsletter (see page 2): https://docs.google.com/viewer?a=v&...C3Sd-q&sig=AHIEtbQgGAG5RduxIgPISYOag97PI5TzWg
.also, don't forget to put a dab of dielectric grease between the new module and the distributor plate. It comes with the new module.
You may try a good used one if you can find one that has the GM logo. New parts are shit anymore. The part store may have a whole batch of bad ones.
With the engine running put vaccum to the vac advance and see if it cuts out ,that will test the pickup wires to see if they are broke in the insulation.Just a suggestion.
i've had trouble with jobber modules didn't last long, borrow one from a working dist and try it the original are the best.
okay so I just tried all the suggestions. everything is fine. Went to the parts store, and what do yah know, they were testing the modules INCORRECTLY! the modules are working as they should. Now i am back to square one....
So you're running full manifold vacuum instead of ported vacuum? Just guessing here, full vac. adv. at idle, throttle opens, vac. goes away, pickup wires flex, engine quits, haven't worked on one of these in a long time but I think I'd try another pickup coil or drop in another complete known good distributor.
yes full vacuum at idle and goes away at throttle. I am about to do that. I have another distributor somewhere in my garage...
just an update for anyone who might experience the same problems and rest the worrying minds of those that helped. I rebuilt the carb and that seemed to do the trick. Thanks for all the help
Great! As it was mentioned earlier, double check your vacuum advance port. It sounds as if you had the dist vac can hooked to manifold vacuum. The carb should have a port that is just above the throttle blade to feed the dist. Base timing advance should be set with vac advance plugged. When the throttle is open and ventury vacuum is increasing, then, the dist vac can gets is vacuum and advances the timing. You may have a bunch more power in your combo if I am right. I think with the set up you have (had), your base timing was advanced. As the thottle is opened, you lost timing (retarded) and was only gained back as the engine reached higher RPM or the throttle was eased back. What advance you may have had was from the mechanical advance of the dist. Sometimes the port is hooked to the right port on the carb, but the primaries are open too far and the timing port is exposed to manifold vacuum. With carb swaps or bigger cams that is common. There are easy fixes for that too.
Interesting! From this end it sounded like an electrical issue. Oh well, it's a mood point at this point. All that matters is that you can ride!
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