STILL will not start...utterly lost
Race Director
Joined: May 2006
Posts: 16,528
Likes: 53
From: Dayton, Ohio
One little trick I've used before is to unseat your plug wires from the plug,leaving a small gap between the plug and the wire. This usually makes the coil work a little harder to snap that spark across a soiled plug.
Safety Car
Joined: Oct 2007
Posts: 3,729
Likes: 267
From: Austin Texas
Corvette of the Year Winner 2017
2016 C3 of Year Finalist
your sypmtom has changed, you have verified spark, next up timing and fuel.
if you push on the throttle do you get a smooth steady steam of fuel from the carb. ?
if vehicle sits you have to prime the carb. if you have spark and gas,
if it coughs and sputters then your timing is Not correct.
if you push on the throttle do you get a smooth steady steam of fuel from the carb. ?
if vehicle sits you have to prime the carb. if you have spark and gas,
if it coughs and sputters then your timing is Not correct.
Racer
Joined: Dec 2008
Posts: 297
Likes: 19
From: arlington TX
A few things -
- you said it had a 'yellow' spark. That isn't a 'good' spark; it should be more blue. Connecting the coil wires (the small ones to + and -) backwards on the coil will produce a bad (yellow) spark. Make sure the wires were re-connected correctly. Small wire from distributor goes to "-" post on the coil.
- How fast is the car turning over when cranked. It should be pretty fast - no "ruh, ruh, ruh". More like "rin, rin, rin" if that makes sense. Bad starter or solenoid or primary (big battery) wires or battery itself.
- Jumper wire from "+" post on battery to "+" post on coil and jump across the solenoid with a screwdriver (it will make sparks; be brave!) from the big middle post on the solenoid to the "s" (small) post on the solenoid will crank and start the engine with the key in any position. MAKE SURE IT IS IN PARK OR NEUTRAL! or it will leave the building! That will eliminate all wiring in the car. It should crank fast with hot (blue) spark. If slow crank - starter or solenoid or battery or battery wires. If weak spark - bad coil or module in the Unilite. That should narrow down the cause.
good luck.
- you said it had a 'yellow' spark. That isn't a 'good' spark; it should be more blue. Connecting the coil wires (the small ones to + and -) backwards on the coil will produce a bad (yellow) spark. Make sure the wires were re-connected correctly. Small wire from distributor goes to "-" post on the coil.
- How fast is the car turning over when cranked. It should be pretty fast - no "ruh, ruh, ruh". More like "rin, rin, rin" if that makes sense. Bad starter or solenoid or primary (big battery) wires or battery itself.
- Jumper wire from "+" post on battery to "+" post on coil and jump across the solenoid with a screwdriver (it will make sparks; be brave!) from the big middle post on the solenoid to the "s" (small) post on the solenoid will crank and start the engine with the key in any position. MAKE SURE IT IS IN PARK OR NEUTRAL! or it will leave the building! That will eliminate all wiring in the car. It should crank fast with hot (blue) spark. If slow crank - starter or solenoid or battery or battery wires. If weak spark - bad coil or module in the Unilite. That should narrow down the cause.
good luck.
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
Thanks for all the help guys. Wish the car was down here with me.
I might pay to have it shipped. I'd prefer to tinker with it myself than try to find a shop.
I'll collect all these ideas and try everything once I get the chance.
Oh, earlier I posted about a voltage difference between at the battery posts while cranking and at the starter solenoid post while cranking of over 1 volt difference.
Is that an indication that my positive battery cable might have internal corrosion or is that normal?
I might pay to have it shipped. I'd prefer to tinker with it myself than try to find a shop.
I'll collect all these ideas and try everything once I get the chance.
Oh, earlier I posted about a voltage difference between at the battery posts while cranking and at the starter solenoid post while cranking of over 1 volt difference.
Is that an indication that my positive battery cable might have internal corrosion or is that normal?
Race Director
Joined: Sep 2004
Posts: 11,874
Likes: 263
From: Arlington Va Current ride 04 vert, previous vettes: 69 vert, 77 resto mod
i think thats ok....you can expect a vltage drop when engaging the starter if its only one volt i say you are in good shape
Instructor
Joined: Jul 2010
Posts: 120
Likes: 0
This isnt meant to be a joke but seriously throw that thing in the garbage. The Unilites are complete junk! Those modules are so sensitive there is some sort of inlien item you can buy so they dont burn out so fast but any sort of spikes will burn them up right away. I had one on my previous car, a 69 Chevelle with a 396 in it. The original module lasted less than a year then I was sent a new one after complaining over and over to Mallory. That one lasted a few weeks then I bought a new one and it lasted a season. Over the winter I put a new MSD Pro Billet in it and put one in my 68 Vert. Really just throw that thing away and get yourself either a ready to run Pro Billett or if you already have the ignition box I think you can save yourself some money on them. I'm pretty sure alot of your issues are from that piece of junk!! I have heard nothing but bad things about those from anyone who have used them!!!!!
Team Owner
Joined: Mar 2002
Posts: 24,160
Likes: 78
Another vote against the unilite here.
You've got to address that cold spark before you go any further. This particular issue can drive men to insanity. Ignition is often not a yes/no problem, but that's how we always try to go about testing it. If you've got a weak spark, you can crank that bitch all day and that cold engine will not fire. You said you heard it coughing on the motor ether. That's because it's got a lower flashpoint than gasoline.
You've got to address that cold spark before you go any further. This particular issue can drive men to insanity. Ignition is often not a yes/no problem, but that's how we always try to go about testing it. If you've got a weak spark, you can crank that bitch all day and that cold engine will not fire. You said you heard it coughing on the motor ether. That's because it's got a lower flashpoint than gasoline.
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Melting Slicks
Joined: Aug 2004
Posts: 2,220
Likes: 6
From: www.Z16.org North/West Pennsylvania
Me too.
Team Owner
Joined: Mar 2002
Posts: 24,160
Likes: 78
I wasn't so much taking a pot shot at a particular brand but rather the fact that he's verified that he's got a weak spark. Just because you're arcing a plug doesn't mean it'll ignite the intake charge. I learned that the hard way.
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
Well once I have the time I will try replacing the plugs and testing the ignition wires.
I'll figure this out, it's just been a frustrating process. The car is a lot more fun when it's moving down the road!
I'll figure this out, it's just been a frustrating process. The car is a lot more fun when it's moving down the road!
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
SHE RUNS!!!!
I should know better. The carb WAS primed with fresh gas, but...the tank had taken on a significant amount of water.
I have no idea if it was during the few times it rained or if I had filled up the tank with bad gas before parking the car.
Either way my Dad and I removed all of the gas, cleaned the carb (again) and reconnected everything.
I had some trouble with the timing but it eventually came in.
Thanks for all the help guys. In the future I'll try not to be a bonehead and make assumptions. The gas in the tank was about 75% useless.
I should know better. The carb WAS primed with fresh gas, but...the tank had taken on a significant amount of water.
I have no idea if it was during the few times it rained or if I had filled up the tank with bad gas before parking the car.
Either way my Dad and I removed all of the gas, cleaned the carb (again) and reconnected everything.
I had some trouble with the timing but it eventually came in.
Thanks for all the help guys. In the future I'll try not to be a bonehead and make assumptions. The gas in the tank was about 75% useless.
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
I think I could afford more initial timing though.
I set it to 8 deg BTDC and with vacuum canister plugged I got 30 degrees at 3000 RPM and 46 degrees at 3000 RPM with the canister connected.
Might look it over again and see if the mark still moves above 3000 RPM
I set it to 8 deg BTDC and with vacuum canister plugged I got 30 degrees at 3000 RPM and 46 degrees at 3000 RPM with the canister connected.
Might look it over again and see if the mark still moves above 3000 RPM
Thread Starter
Racer
Joined: Oct 2008
Posts: 276
Likes: 5
From: Aptos, CA
Thanks I'll try giving it a few more degrees of advance.
I wish I knew if I actually had a L46 rebuilt to factory spec, or if when it was rebuilt it was made more mild to behave on street gas. That info was lost to history when I bought the car and no receipt paper trail existed with a number for me to call.
Oh well, I guess advancing the timing more and running on 91 octane will tell me...as long as I'm careful.
I wish I knew if I actually had a L46 rebuilt to factory spec, or if when it was rebuilt it was made more mild to behave on street gas. That info was lost to history when I bought the car and no receipt paper trail existed with a number for me to call.
Oh well, I guess advancing the timing more and running on 91 octane will tell me...as long as I'm careful.