mystery wire...

[77c15]

In one of my other posts I mentioned that I received an American AutoWire OEM FactoryFIt engine wiring harness for my 74. Being that it was built to original GM specs, the harness is wired for a points type distributor and coil. I have a HEI distributor and am wondering about the mystery yellow wire that runs along the harness from near the distributor down to the starter wires. When I hooked it up to the S terminal and then connected the battery, it caused a constant crank. Where should this wire go? I've played with turning the distributor a little at a time and have got nothing more than a minor backfire from the engine. I double and triple checked the firing order for the plug wires and that the dist was facing number one during the initial startup trial. I'm sure this is a major wire due to the fact that when I swapped the truck over I took the coil (+) wire and put a spade terminal on it to run to the BAT terminal on the HEI. I have connected that end of the yellow wire to the distributor, but was wondering if I should connect the other end to the R terminal on the starter or what. The motor is out of 69 vette (.030 over). Let me know what you guys think.

[VileZambonie]

That would go to the R terminal which would serve no purpose if you are using HEI. The R terminal is energized only during cranking. This provided full 12 volts to the coil during cranking for easier starts. Once the key is released it is de-energized and the coil recieved approx 9 volts through the resistance wire. This was used to prolong the life of the breaker points. With HEI you wan't 12V key on at the BAT terminal on the dist cap.

[77c15]

Where do you recommend I pull the key on 12 volts from? Thanks for the quick and painless reply, Vile!

[VileZambonie]

I'll take a look at my 74 when I get a chance and see where I tapped the bulkhead connector.

[77c15]

That's alright Vile, I tapped it into the IGN spot on the fuse block. I appreciate the help, though. Now i've got  to wait on the rain to stop and get the distributor turned 180 to see if I can get her to do anything other than backfire.

[VileZambonie]

I was working on stripping down the engine compartment tonight and I realized I have an MSD ignition system anyway (duh brain fart lol) but what you did is perfectly fine.

Good luck with your backfiring

[77c15]

Fixed the backfire:

turned the dist 180 and she fired right up. I either have a bad freeze plug or a bad set of intake manifold gaskets, though. Coolant was pouring from what looked like the back of the head and around the oil filter, so i'm guessing intake gaskets just because that's the most recent thing done to it and I was pissed that the gaskets I used were bent in a perfectly fine looking box. I grabbed another set. Perks of working at AutoZone, I guess. I'm gonna change the oil again and pull the intake manifold to make sure. Thanks again Vile for your help with this.

[VileZambonie]

If you work at autozone grab a pressure tester and pressure test it to pinpoint your leak before you rip it all apart again just to be sure. Good luck!

[77c15]

Neighbors got a pressure tester, gonna get him to test it in the morning. I believe it's a 90% possibility on the intake manifold gasket. That set of gaskets being bent and the pain in the you know what job of torquing stuff down with an extension and a flex adapter doesn't always work out. I still don't know any secrets to getting those 4 inside bolts tight without using an extension and/or flex. Any help in this department?

[VileZambonie]

use a 1/4 in drive shallow flex socket 

[Bowtie Bomber]

Fixed the backfire:

turned the dist 180 and she fired right up.

Same exact thing that happened to me a couple days ago. =P

[77c15]

That 1/4" flex worked wonders!!! My neighbor just happened to have a 7/16  shallow flex from snap-on. Now i've either got a fried coil or control module. Check for 12 volts at the BAT terminal on dist cap and it's fine, but no spark to number 1. I put a used spark plug and a screwdriver in it and attempted crank with no spark. I might rebuild that distributor. It's in dire need of it. Lots and lots of corrosion on the curve kit.

[77c15]

Magnetic pick up coil was shot, so a trip up to the AutoZone I work at and we walked out with a new vacuum advance, pick up coil, and an ordered coil ground strap. Gotta love HEI. I just wish the curve kit didn't look like a Katrina submerged victim.

[VileZambonie]

You might as well throw a new module in it while you're in there.

[77c15]

I did actually get a new control module before anything else thinking that was the reason for the no-spark because the coil resistance was fine. Magnetic pick-up coil fried (resistance 0.000) and the shaft was extremely rusted and stubborn during removal. I'm concerned that I might be throwing all this money into rebuilding it for nothing. Sucks if it still doesn't work and I have to replace it.