Rhubarb

Well ... My 74 convertible arrived today (trucked down from CT). My wife started it up ad drove it off the truck. I got home from work and fired it up .. took it around the block. No problems.

Came back after dinner ... cranked it .. and it would not start. I tried various combinations of pumping the gas, holding the pedal down ... never started ... never even sputtered. Feels like no spark.

The car has an MSD 6 ignition and an MSD Blaster 2 coil. Cap and rotor are brand new. It was dark and I did not pull a wire to see if there is spark.

There was a small spark that jumped on the + terminal of the coil. I could not tell where it was jumping to. It popped once every second. I checked the wire and connector and everything is tightened down.

I am new to this old style ignition system ... am I missing something? Do coils go bad?

Pics of the car coming soon !!

wombvette

If you can see a spark anywhere near the coil, that is most likely the problem. You should however check the spark at the plugs, just to make sure.

The Wanderer

If you have a spark at the + terminal it is trying to go to ground there rather than to the distributor. Check everything in the area and see where it can ground. You might call the old owner also, he/she may know of this problem. I doubt that it just popped up and it doesn't sound serious. Enjoy your new Vette and post pictures :D :D :D

Jughead

I agree with Wanderer. My (+) teerminal of the coil kept shorting out on my air cleaner base! Took me a while to figure that one out. I moved the coil about an inch and the short stopped.

Good Luck. Your '74 will repeatedly test your problem solving ability and patience.

GaryS

If you have a spark jumping from your coil I would suspect that, but I have a bigger problem with why the spark is jumping at all. Are you sure your wires are good? I know nothing about the MSD ignition system but if a spark is jumping from the coil instead of traveling through the coil wire to the distributor I would suspect that.

Gary

Rhubarb

I will play with it more today. The spark looks like it is jumping back into the stem of the coil itself (right below the wire to the distributor).

I have the original Delco coil that I could swap out as well.

Needless to say ... my wife is not too impressed so far :(

Alwyn678

Rhubarb..........I am guessing you listen to a country station here in Atlanta Ga........I am excited to see another 74 convertible in Town....I can hardly wait to check out your new ride.......I live in Marietta so we are practically neighbors...Sorry I have nothing to add regarding your problem....Your wife will be impressed soon enough though......It does sound like u need a flamethrower coil though


[Modified by Alwyn678, 10:38 AM 9/19/2001]

TheVetteDude

I had this problem on my boat engine. Rather than move anything I just coated the terminals on the coil with liquid electrical tape.

Gary

Rhubarb

It's Fixed !!!!!

Turns out the MSD Blaster 2 coil was bad. I found the original Delco coil in a box of parts I got with the car ... swapped the coils and it fired right up ! I hope all the repairs are this easy !

Should I replace it with another Blaster or is there something better? I have an MSD 6 Ignition system.

Took it up and down the street a few times ... this is going to be FUN !!

Next stop ... rebuild the carb .. paging Mr. Lars

71coupe

That delco coil should be fine with your MSD.
What plug wires are you running & what spark plugs/gap?

The Wanderer

You'll love Lars and the quality of his work. I'd sure have him look at your distributor at the same time ... but be warned.... he loves points :D :D :D

Alwyn678

I would go with the Flamethrower coil........From Pertronix....Throws a wicked spark...........

Rhubarb

The cap and rotor are new MSD. Taylor 8mm wires, not sure what plugs or gap.

The engine was built for 400HP. Everything that was done is top notch. There is less than 1000 miles on the rebuild.

However, the carb is the original Q-Jet and has never been rebuilt. The idle is rough and I am not sure the secondaries are opening properly.

Exhaust is original as well. It was a California car so it has cats !!!

Time to start a list.

71coupe

I believe you have fixed the problem, but the root cause of the problem may still be there. Sorry to pee in your Cherrios.:(

If you have too much gap or tons of resistance in the wires or plugs, it will cause the coil to work hard and possibly burn up.
The other thing that may cause the coil to burn up is a bad motor ground.
MSD's put out some big power to the coil, and a bad eng ground could fry the coil.
I recomend checking the plug wire resistance, check the plug gap - no more than .040", & install a ground strap on both heads that goes to the frame.
Also check & clean the frame to the battery ground strap.





[Modified by 71coupe, 2:35 PM 9/19/2001]

Steve Grodin

'74 Corvettes did not come with cats, inclulding California cars. '75 was the first year for cats on corvettes.

Rhubarb

Interesting ... i had not looked. Just going by what the former owner told me. I will jack it up tomorrow and take a look.

Thanks

rrent

Rhubarb

Congratulations on the new car and getting it running.

Talk about your wife being impressed --- the first day I brought my '72 Blazer home the linkage from the column shifter to the auto tranny had come loose - so I had to yell out to my darling wife to stick a 2X4 under one of the tires so I wouldn't roll down the drive way :D