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Old 07-30-2023, 08:30 PM   #1
ladybugblazer
Registered User
 
Join Date: Jul 2023
Location: Houston Texas
Posts: 11
Question Question about 350 HEI and Mystery tubing

After watching too much Uncle Tony's Garage I decided to have a early midlife crisis and buy a classic with a carb. I decided to get a 79 K5 Blazer and am running into some issues with the HEI on it.

Story starts like this. I just got the truck and I go to get her inspected. She turns on and runs like a beauty; mechanic agrees. Car passes inspection and I go to turn it on to head out. For some reason I tried to turn on the car the and it would crank but wouldn't turn on. I talk to the mechanic about it and we saw gas coming into the carb and heard the fuel pump. We decided maybe it got flooded, so I decided to wait around 20 minutes to try and crank again but nothing. At first I thought maybe it got vapor locked because its been around 100 degrees here in Houston but that was not the case. After around 30 minutes me and the mechanic start looking around we test the battery and try again but battery was good. Carb still smells like gas and cars still cranking we decide it's gotta be an electrical issue. He jumps in and starts wiggling the wires on the HEI coil and we notice the cap has been zip tied. After some wiggling around I turn the key and she turns on like a beauty again (SEE PICTURE 1A, Blue circle). We talked a bit and he says probably something is up with that distributor coil wire and recommends I should run an MSD on it. Come 15 minutes later I get home and let the car run for a bit. The drive back was flawless by the way. After a bit in front of the garage car shuts off again. I decide to take a break and go swim because its hot outside.

I come back a couple hours later, give the pedal a half pump and turn the key nothing. Pop open the hood and wiggle the wires around on the HEI ignition coil. I crank the key car turns on like a beauty and that's how she is now.

So I dug around a bit later and I also noticed a clear tubing that is connected to a fitting off the back of the intake under the HEI Distributor (SEE PICTURE 8 PINK CIRCLE)and runs through the firewall into the cab into what seems like nowhere. The tube also has some clear liquid in it with alot of air (SEE PICTURE 1A, 2 PINK CIRCLE). I was thinking maybe this was some kind of nitrous tubing or something but I'm not sure. It also has a 8k RPM Gauge installed inside

Anyways, the situation is I've been thinking about replacing my HEI coil with a Pertronix Flamethrower but I noticed the leads in those are Red and Black/white while mine are red and Teal. Would this be compatible? Also does anybody have an idea why I might have to be wiggling them around? Maybe the coil is fine and the wire installation under the cap just needs to be redone? Lastly what is this random tubing doing around here?! I've been trying to do some research on it but I can't figure it out and it's driving me nuts.

Thank you all,
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Last edited by ladybugblazer; 07-30-2023 at 08:37 PM.
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