weak\dead battery + MSD 6AL = sputtering,learching and death????
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,286
Likes: 172
From: Lake Wylie, South Carolina
weak\dead battery + MSD 6AL = sputtering,learching and death????
The Vette has not been cranked in about 2 weeks while I was insalling seat belts and guages. Last night I tried to crank it and never could so I gave up till his morning. In the proccess I ran down the battery which was bought new about a month ago. This morning I did some troubleshooting and found that the power wire from my MSD box had melted to the header and grounded itself out. After fixing the wire the car fired right up but then started sputter really bad and back fired a couple of times then died. I tried to start it again and the bettery just clicked. I jumped it off with my truck and it fired up but then sputtered and died again. Is this possibly happening because the MSD box draws so much current that what little bit of charge I had in it or put in it from jumping it off was immediately sucked out of the battery since it did not run long enough for the alternator to put any charge back in it? Any other possibilities? It was running great when it was parked 2 weeks ago.
Thanks
Thanks
Thread Starter
Safety Car
Joined: Oct 2000
Posts: 4,286
Likes: 172
From: Lake Wylie, South Carolina
Thanks big_G. I wound up buying a new Optima battery yesterday and the car fired right up and ran great. I have the other battery on the charger and will use it for a spare.
Thanks
Wade
Thanks
Wade
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I'm by no means a battery expert but I have always heard and done a slow charge, 2 amp or less for 12 to 24 hours to properly and fully charge a battery. When I have 10 amped the battery it does heat up quite a bit more. I have done this on my boat and car batteries for 30 years and had good battery life. 
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
Also, you might want to check out your alternator. I don't know how much your MSD draws, but a stock alt should support the ignition needs of your Vette without a battery connected. I tested on my '77 once when I was troubleshooting a bad battery / alt issue. I removed the ground, taking it out of the circuit totally. The engine ran fine, drove me around the block, and I parked it and I killed. I removed the battery, had it tested, and it needed to be removed.
Burning Brakes
Joined: Nov 2004
Posts: 821
Likes: 0
From: Ontario
Had the same problem on my 71 after I installed MSD and electric fan system. Removed my alternator had it checked and it was putting out only 27 amps. Upgraded to a 94 amp alternator and this has cured the rough idle problem.
Team Owner
Joined: Aug 2006
Posts: 24,125
Likes: 15
From: Columbia Missouri
It would probbaly be a good idea...if your alt is bad, to convert to the newer CS style. They are way more efficient and can be adapted very easily. You'll more idle amps and a brushless design that lasts a lot longer too.
