I posted something similar a few days ago on
alt.autos.4x4.chevy-trucks, but under a more generic subject line...so
I figured I'd repost here where there's more traffic.
Basically, here's the details: Months ago, I came home from work and
immediately went about changing the jets in my Edelbrock carb to lean
it out. The engine was hot, and when I had it (almost) back together I
tried to start it. Well, the fuel line hadn't been reconnected to the
carb (oops), so cranking the motor just shot gas all over the hot
engine and started a fire. Months (and a replacement wiring harness)
later, I really need to get the truck started THIS week. I'm moving in
2 weeks, and will no longer be within walking distance to work.
Truck is a 1986 K5 Blazer, 4x4, 350ci with an Edelbrock 600cfm (elec.
choke, vac. secondaries). I installed the new harness and I believe I
have everything necessary connected. I don't have the AC compressor's
power wires connected...
The HEI distributor took quite a hit in the fire, and most of it was
replaced. It uses/used the 5-pin ignition module that connected to a
very basic ECM of sorts--the ESC (elec. spark control) module, which
retards spark based on input from a knock sensor. Being that the
harness that connected the module to the ESC was shot after the fire, I
made a new one. I installed a new ignition module and new condensor.
Truck won't start. I *think*
I'm getting fire to the plugs. I
installed an aftermarket tach that I'd bought, and connected it to the
"tach" connection on the HEI. When I turned the engine over, it does
its thing and jumps up to about 1000rpm.
When that didn't work, I questioned the integrity of my home-made
harness to connect the ESC to the ignition module. I had a spare
(brand new) 4-pin module on hand, so I eliminated the ESC althogether.
I removed the plastic shell of the pass-thru connector that ran between
the 3-pin side of the module and the ESC connector, and serves as the
connection to the pickup coil. With the metal connections exposed, I
pushed them onto the 4-pin module, and essential converted the HEI to
the earlier style, 4-pin module (sans ESC).
Following me so far?
There was no difference when I tried to start it. I will add that I
had accidentally forgot to connect the condensor to the ignition coil
the first time around. After replacing some parts and connecting it
properly, it SOUNDS different, like it's trying to start, whereas
before the coil was in the circuit, it just turned over, with a
While trying to start it, heavy fumes are coming out the tailpipe, so I
know it's getting gas.
Also...the fire was on the back of the engine and firewall (ironically
enough). The HEI's cap was melted, among other things. That's mainly
due to the fact that the fuel line was laid aside and pointed back
toward the firewall when I tried to crank it.
Could the fire have damaged the carb in some way? Granted, the last
time it ran, I turned it off and swapped the jets in the carb, so maybe
I should try putting them back to stock first.
Can someone please advise me on testing the HEI? I can't imagine that
the pickup coil was damaged. There weren't any blackened parts
underneath the rotor when I pulled the distributor--so I don't think it
necessarily saw any more heat than it would during normal use. I
cleaned it out with a non-conductive cleaner used for alternators and
electric motors. The ignition coil and pickup coil are the only two
pieces that were not replaced.
I feel confident that I properly aligned the HEI when I reinstalled it.
I had marked the pickup coil's inner and outer pieces with bright nail
polish before removing it. I didn't see anythign weird about the
distributor gear that would indicate that it had to be connected to the
cam in a specific way (I've heard of distributor having to be aligned
exactly or else they wouldn't seat). It seats well and it obviously
turning, as I've had the cap off several times and it's always pointed
in a different direction.