cheap crappy ignition switches?
 

shortly after building a bbc last year for my 77, i had a no start condition (cranked fine), and chased it to bad contacts in the ignition switch. i replaced it with a unit from autozone, and i didnt have an issue for the past year.
2 weeks ago i once again had a no start condition. it seemed like i was once again having low voltage to the distributor (HEI, resistor removed from distributor wire). i once again replaced the ignition switch with another unit, this time from napa. after replacement, truck fired no problem for the past 2 weeks.
this morning i went to drive my truck to work and once again, cranks fine but no start. truck starts fine if i run a jumper straight from battery to distributor batt terminal. im going to replace the switch again soon.

is this a seemingly bad string of ignition switches, or is there some other issue at play making these switches go bad?

Re: cheap crappy ignition switches?
 

There is an adjustment on the ignition switches where it mounts. If it is off a hair or not tightened securely, the conditions you are having will occur.

Bench test it before you try another one. This video helped me out with mine. Once I got the areas figured out (I also marked it with a sharpie so I could see it when I mounted it). Once installed, make sure the screws are secured tightly so it would slide at all during use.

https://www.youtube.com/watch?v=GYaSCV2ICwA

Re: cheap crappy ignition switches?
 

If the switch bench tests good then it's likely adjustment.

If not you're on the cheap crap Chinesium parts merry-go=round...

Did you get the Mileage Plus brand or Echlin at NAPA? I wouldn't trust a Mileage Plus switch as far as I could throw it.

Echlin used to be Standard Motor Products. Not sure whether they're still making them for NAPA or not. NAPA is re-boxing/re-labeling a bunch of DORMAN Chinesium parts now so...

AC Delco used to be a goto on these kinda things but they are now AC Delco Chinesium...

Autozone Duralast is either Wells or BWD. Again Chinesium. Neither are trustworthy in my book.

Re: cheap crappy ignition switches?
 

yeah, the one in there now is the mileage plus unit. ugh. they had the echlin one but i cheaped out lol.
when i installed it, i tried to set it approx. in the same spot of the slotted mounting holes as before.
i will try playing with the mounting position before pulling it out and bench testing it.

Re: cheap crappy ignition switches?
 

just an update, i played with the mounting position for quite a while with no luck, so i went and picked up a echlin one, and it fired right up.

i guess im in the **** part roulette. bummer.

Re: cheap crappy ignition switches?
 

Echlin used to be decent quality. Hopefully they still are.