no spark with MSD box
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Burning Brakes
Joined: Jul 2003
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From: Angola IN
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no spark with MSD box
While I'm waiting to get the forum gurus at MSD to let me in their forum, I figured I would ask here and see if anyone can help.
Engine is a zz4 with less than 1000 miles, I put it in my 70 3 years ago, and haven't had any issues.
Simple three wire set up to the MSD equipment.
Here is what I have ready to post to the MSD site:
To start off, I have a 1970 vette with an msd 6al box, Msd tac drive distributor, and an msd coil (been running this set up for 3 years with no failure). I got the car out after its winter sleep, started right up, and I let it run for about 20 min. then shut it off. Went back out to get it back into the garage and I had/have a no start. Cranked on it and flooded the plugs out, changed the plugs, it started for about 5 seconds, and since then it is a no start all the time. This was two weeks ago, been working with it every weekend to get it going. It is a no spark situation.
Here’s what has been tested:
The engine has no spark to the plugs, it has been tested with the green and purple false trigger test more time than I can count (passes every time)! I have replaced the trigger in the dist., the cap and rotor. The plugs wires all check out, I have 12v on both the large (constant power) and small red wire (from ign switch). Ground is good to the box, dist., and all ground straps ohm out, both to chassis and engine.
We removed the dist. Bench tested the trigger, reconnected the dist. to the MSD box while out of the engine (with temp ground wire on dist. shaft), and rotated it by hand with the ign. in the on position, it throws spark to each plug wire while out to the engine (now before you say it’s a camshaft issue not turning the dist., it does rotate the dist. while in the engine). I put the dist. back into the engine, at tdc, and NO SPARK while cranking (Checked for spark with no. 3 wire off and screw driver to ground)!! We even placed a temp ground wire to the dist from a known good ground.
This led me to believe it is an issue with the ign. switch; I tested for 12v at each of the red msd wires while both in the run, and start position. I have 12.6v in run, and 12.6v with it in start without the energize wire attached to the starter (with the energize wire attached and cranking the motor, voltage drops to 10.7v. (msd guide says the box will work with 5v min.) So it’s not the ign switch.
So at this point I am stumped and back to square one, with a no spark, no start with the dist. installed.
Does anyone have a clue? Is this an issue with the msd box?
At this point I am ready to remove all of the wiring from its current circuits and toggle the reds, and push button start the starter. I don’t know what this would solve since all of the current wiring has been tested and passes each and every time!
I would appreciate any and all ideas at this point, for three years it has worked great, and I am at a impasse at what to try next.
Thanks guys.
Engine is a zz4 with less than 1000 miles, I put it in my 70 3 years ago, and haven't had any issues.
Simple three wire set up to the MSD equipment.
Here is what I have ready to post to the MSD site:
To start off, I have a 1970 vette with an msd 6al box, Msd tac drive distributor, and an msd coil (been running this set up for 3 years with no failure). I got the car out after its winter sleep, started right up, and I let it run for about 20 min. then shut it off. Went back out to get it back into the garage and I had/have a no start. Cranked on it and flooded the plugs out, changed the plugs, it started for about 5 seconds, and since then it is a no start all the time. This was two weeks ago, been working with it every weekend to get it going. It is a no spark situation.
Here’s what has been tested:
The engine has no spark to the plugs, it has been tested with the green and purple false trigger test more time than I can count (passes every time)! I have replaced the trigger in the dist., the cap and rotor. The plugs wires all check out, I have 12v on both the large (constant power) and small red wire (from ign switch). Ground is good to the box, dist., and all ground straps ohm out, both to chassis and engine.
We removed the dist. Bench tested the trigger, reconnected the dist. to the MSD box while out of the engine (with temp ground wire on dist. shaft), and rotated it by hand with the ign. in the on position, it throws spark to each plug wire while out to the engine (now before you say it’s a camshaft issue not turning the dist., it does rotate the dist. while in the engine). I put the dist. back into the engine, at tdc, and NO SPARK while cranking (Checked for spark with no. 3 wire off and screw driver to ground)!! We even placed a temp ground wire to the dist from a known good ground.
This led me to believe it is an issue with the ign. switch; I tested for 12v at each of the red msd wires while both in the run, and start position. I have 12.6v in run, and 12.6v with it in start without the energize wire attached to the starter (with the energize wire attached and cranking the motor, voltage drops to 10.7v. (msd guide says the box will work with 5v min.) So it’s not the ign switch.
So at this point I am stumped and back to square one, with a no spark, no start with the dist. installed.
Does anyone have a clue? Is this an issue with the msd box?
At this point I am ready to remove all of the wiring from its current circuits and toggle the reds, and push button start the starter. I don’t know what this would solve since all of the current wiring has been tested and passes each and every time!
I would appreciate any and all ideas at this point, for three years it has worked great, and I am at a impasse at what to try next.
Thanks guys.
Former Vendor
Joined: Aug 2006
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From: Jeffersonville Indiana 812-288-7103
St. Jude Donor '08-'09-'10-'11-'12-'13-'14-'15
I've three defective MSD 6AL boxes and all failed the spark test per the instructions. If it is a pretty new box, you can just exchange it. If it's an older one you can send it to them and they will fix it.
I still have one of these on one of my cars and have had great success with them in the past. I don't know if they just had a bad batch get out or what.
If you have followed the spark test as outlined in the installation manual and the unit fails, verify all the wires and if it still is a no go. . . I think it's done.
IMHO,
Willcox
I still have one of these on one of my cars and have had great success with them in the past. I don't know if they just had a bad batch get out or what.
If you have followed the spark test as outlined in the installation manual and the unit fails, verify all the wires and if it still is a no go. . . I think it's done.
IMHO,
Willcox
