67 sometimes doesnt start.
#1
67 sometimes doesnt start.
I'm a newbie to the forum so please bare with me. I recently acquired a 67 rs 396 when my dad passed away. The car runs ...most of the time. Based on info I can get from my mother there were times the car wouldn't start. My dad carried around a piece of jumper wire with alligator clips in the car. She states that sometimes (both when the car was hot and cold) that it wouldnt start. He would hop out and connect the jumper wire, hop back in, turn the key...and vroom.
I'm looking for ideas on what he was doing, and ultimately how I can diagnose and fix the problem. I have not had a chance to really get under the hood. I do know that there is a msd blaster 2 coil, and something has been done with the alternator but I dont know what yet. I dont know ok w if its hei, mad, maybe pertronix, I'm hoping to get over there today and get a look. Any ideas would be appreciated.
p.s. I'm pretty mechanical and have most tools needed to get the work done, but I am not a true "car guy".
brian
I'm looking for ideas on what he was doing, and ultimately how I can diagnose and fix the problem. I have not had a chance to really get under the hood. I do know that there is a msd blaster 2 coil, and something has been done with the alternator but I dont know what yet. I dont know ok w if its hei, mad, maybe pertronix, I'm hoping to get over there today and get a look. Any ideas would be appreciated.
p.s. I'm pretty mechanical and have most tools needed to get the work done, but I am not a true "car guy".
brian
#2
determine if its a HEI or Pertronix kit dizzy
confirm the wire attached to coil +,(there would be a yellow and white one) if it is a HEI type dizzy that the white wire is not the resistance type but has been replaced with standard copper wire. Most just run a new wire from IGN tab on fuse block and tape the stock resistance wire back into the harness
If your Dad converted to single wire alt maybe he was jumping from alt + post to coil +...just a guess.
confirm the wire attached to coil +,(there would be a yellow and white one) if it is a HEI type dizzy that the white wire is not the resistance type but has been replaced with standard copper wire. Most just run a new wire from IGN tab on fuse block and tape the stock resistance wire back into the harness
If your Dad converted to single wire alt maybe he was jumping from alt + post to coil +...just a guess.
#3
Welcome, Brian, to the club.
Sorry in reading of Father passing away.
Onto your new toy - since she has an external ign coil, it's not GM's HEI.
Next you should pull dist cap and see if a point set is in place, and if it is, reset gap, 0.019". If Petronix, you're good to go.
Ensure yellow wire from solenoid is hooked into coil harness.
Another troubleshooting aid, remove the MSD harness from the coil and connect remaining wires to their existing coil post, or add jumpers across terminals on the attached board.
You might even hook a small light bulb and tape to under side of dash and connect leads to ground and coil + post ensuring starting ign power from solenoid when starting.
No bulb, no power, bad solenoid disc & contacts.
Sorry in reading of Father passing away.
Onto your new toy - since she has an external ign coil, it's not GM's HEI.
Next you should pull dist cap and see if a point set is in place, and if it is, reset gap, 0.019". If Petronix, you're good to go.
Ensure yellow wire from solenoid is hooked into coil harness.
Another troubleshooting aid, remove the MSD harness from the coil and connect remaining wires to their existing coil post, or add jumpers across terminals on the attached board.
You might even hook a small light bulb and tape to under side of dash and connect leads to ground and coil + post ensuring starting ign power from solenoid when starting.
No bulb, no power, bad solenoid disc & contacts.
#4
Some new info
Thanks for the quick responses. I swung by this morning and it fired right, which is the case most of the time. It has an msd pro billet 8360 alt and a blaster 2 coil if that changes anything. In a box I found a whole other 8360, cap, and coil. So...my guess is he tried replacing most of those but got nowhere. And fyi, when I got over there I realized it was a 68, my mom always called it a 67.
#5
you really need to pull the cap and see if it a points or Pertronix dizzy. If points than change them. If the later confirm the resistance wire thing I mentioned has been bypassed. If it has and has a Pertronix than the module may be bad or installed incorrectly (to close or to far away from rotor)
#6
Some new info
It's not a pertronix, it's the msd 8360 with all its internals (https://www.summitracing.com/parts/m...saAmfjEALw_wcB). It does not have the resistance wire and appears to have been routed with new copper wire per the wiring diagram. A cannot confirm the connections at the actual ignition switch but at the alt and coil (and as far toward the dash that I can see) its all new stuff.
#7
The present MSD box uses the OE cloth-covered wire for its own 'turn-on the box' signal as MSD box has its own power/ground wires - key ON, box turns on.
The OE point set is used for triggering the box in making multiple sparks per cylinder fire, so no massive current goes through the wire, so it should be okay., if installed.
Ensure good connections of all wires, including power and ground.
I remember looking at the ignition with an ignition scope and about two sparks happen at high RPM, more at lower RPM because more time in generating spark.
Of course, it runs good when its working ...
The OE point set is used for triggering the box in making multiple sparks per cylinder fire, so no massive current goes through the wire, so it should be okay., if installed.
Ensure good connections of all wires, including power and ground.
I remember looking at the ignition with an ignition scope and about two sparks happen at high RPM, more at lower RPM because more time in generating spark.
Of course, it runs good when its working ...
#8
Well, the 1st thing you should change is your handle to Brian1968. Ask your mom if it was a crank but no start. He probably used the jumper to hot wire the blaster coil with 12V from the battery. pull the wire off the coil + side and see how many volts you have at the wire end when you turn the ignition switch to the on position. Do NOT test the volts with the wire attached to the coil (as per MSD). I have the non vacuum advance version of that distributor with blaster coil in my Camaro and it has been flawless for me. I run an MSD 7AL3 ignition box.