K10 Project

[JoeliusZ28]

Full 2.25" dual system with h-pipe and aerochamber mufflers. rolled edge tips in the factory location behind the tires. Should be a modest looking/sounding setup.

[MP81]

Oh its coming off i just dont want it in an undrivable state. The exhaust has been decided on i just need to order the parts and shedule an appointment now.

Makes sense. Those original ones weigh something like 20 lbs.

[JoeliusZ28]

That sounds about right its heavy

[JoeliusZ28]

Well I got everything finished up tonight. Jumped in the truck to take it for a test spin and .... no spark again. No clue why this time. If anyone knows these things I could use some help. I took the distributor apart 4 times and I cant find anything wrong. As craigslist would say it "ran when parked" so idk what the deal is.

I can think of two possible explanations:

1) The distributor may have gotten damaged when i dropped the trans out. I think this is unlikely however. The story was my chilton manual conveniently neglected to mention that the distributor cap must be removed to get enough angle on the trans to slide it back out of position. The result of this was me being completely unaware and banging the distributor into the firewall trying to get the trans out. The distributor cap dislodged itself because of this (its held on with spring loaded clips), but it doesnt appear to have to have taken any damage at all, at least that i can see.
2) I had to cut and re-weld the exhaust in order to get the trans out. Disconnected both terminals of the battery before i did this. possible i fried something?

Any ideas are appreciated....

[MP81]

Well, there's no physical connection between the distributor cap and anything inside - just the clips that hold it on, and the wires that connect to the coil.

This page seems to have a good way to test the coil to determine if it is at fault - and auto parts stores can check the ICM.

http://www.hotrodders.com/forum/test...le-103662.html

Should only be a couple wires going to the coil...battery voltage and a tach feed out.

[JoeliusZ28]

Awesome thanks Kyle. And i think i forgot to mention i did confirm voltage is getting to the coil with the ignition on.

[MP81]

Ok, so then either the ICM or the coil is malfunctioning, or the spark isn't getting from the coil to the rotor and then to the plugs. But other than the ICM, that all sounds like causes that usually cause it to gradually run shittier and shittier until you replace them...not die instantly.

[MP81]

http://67-72chevytrucks.com/vboard/s...ad.php?t=58641

[Lucky SOB]

Is it a points style distributor? Had to replace the points on the GTO to get spark.

[MP81]

Is it a points style distributor? Had to replace the points on the GTO to get spark.

No, HEI with ESC...but also vacuum...still lost on that one

[JoeliusZ28]

Yeah its an HEI style. It is both vacuum and electronic control but the only thing electronic control does is retard when knock is detected. Its not necessary and many people remove it... Which is beginning to look like what ill be doing. Ive been wrenching on this thing a month now and its beginning to lose its appeal.

[MP81]

Yeah its an HEI style. It is both vacuum and electronic control but the only thing electronic control does is retard when knock is detected. Its not necessary and many people remove it... Which is beginning to look like what ill be doing. Ive been wrenching on this thing a month now and its beginning to lose its appeal.

Well, it is old...that should be expected.

Left-field theory, but your tach wire isn't shorted, is it? Unplug that wire and give it a shot - it can cause issues and stop the car from sending spark.

[JoeliusZ28]

Yeah, i think id be more patient right now if it was in my own garage. Working on things with my dad hovering over my shoulder wondering when its going to be done and out of his garage just makes me anxious.

It doesnt have a tach at all yet. Its sitting on the bench seat waiting to be installed

The good news here is that it looks like i have pretty much every possibility eliminated other than the electric spark control, which i found last night is a simple bypass:



The bad news is that if i do this im going to have to reset the timing. And to really get it running correctly im going to need to mess with the spring weights as well as adding an adjustable vacuum advance because its probably not going to run right if just delete the ESC and adjust base timing. Stock springs dont advance quickly enough and stock vacuum can advances way too much, ESC negated the effects of that.

[1BADAIR]

Didnt get the harness in the bellhousing did ya?

[JoeliusZ28]

Didnt get the harness in the bellhousing did ya?

Harness was fully visible iirc, but thats a great question ill check that.