HEI distributor keeps going out. WHY?

[nac593]

so i replaced EVERYTHING 12000 miles ago. new engine(290 hp crate), distributor from chevy dealer.and everything under the hood is new. ir ran great and then at about 5000 miles it just cranked and cranked with no spark. I changed the coil with parts from napa. it started right up. at about 8000 miles same exact thing. jumped in to start it and it just cranked. bought coil from kragen and it started right up. now i am at 12000 miles. jumped in last night and same thing.just cranks so i assume its the same thing. WHY does this keep happening?

[rockc]

Had the same thing happen to me. Tried rebuilding it myself. Kept replacing a coil, mod, cap, etc, So ended up buying a new rebuilt dist. from checkers for around a $100. That was 40000 miles ago and still running good. Might check amount of voltage to it also.

[cdowns]

when installing HEI you did run a new power supply line? have you ever cleaned and checked ALL your ground connections? have you used the GREASE when replacing modules?

[drbyrdman]

The stock dist. wire has resistance for points. That will kill a HEI if it was not taken out and replaced so the Hei gets a full 12 volts.

[bigblockorange]

Check the voltage on the wire to the HEI from the firewire wall. It may be less than 12 volts if so pull the harness and remove the wire and replace it with one from a newer truck 74 and up they are a non-resisted wire. I bought a truck that did the same thing. BBO

[chas350]

x2

[hounddogs!]

Make sure the 12V is coming from an ignition-on source. The module doesn't need to see 12V constantly, like if you went straight to the battery.

[Wrenchbender Ret]

There is a ground strip that goes under the coil to the center term. on the outside that goes to the dist housing. Sometimes when a guy changes the cap he leaves it in the old cap. It can cause all sorts of component failures.

[nac593]

i did run a new 12v wire. and that ground strip is in there

[LONGHAIR]

Originally Posted by Wrenchbender Ret

There is a ground strip that goes under the coil to the center term. on the outside that goes to the dist housing. Sometimes when a guy changes the cap he leaves it in the old cap. It can cause all sorts of component failures.

That was going to be my answer, I have seen that happen more than once.

[cparman]

X3 I have seen this drive some really good techs crazy. Make sure it is there.

Originally Posted by Wrenchbender Ret

There is a ground strip that goes under the coil to the center term. on the outside that goes to the dist housing. Sometimes when a guy changes the cap he leaves it in the old cap. It can cause all sorts of component failures.