Electrical Shutdown at Positive Stud Connection

[MrCreosote]

I've had this happen 3 times.

The Positive stud is bolted tightly and the car shuts off. I pull over, loosen and retighten the stud bolt and all is good again. Today I had this happen twice about 1 mile apart.

THEORY: The OE loom has 2 heavy eye terms that bolt on that stud. Addons to the car resulted in a light gauge but big eye term also stacked on that stud. I was putting the light gauge eye on the bottom of the stud because of concern that the nut would tear it up. However, I'm beginning to suspect that the heavy eyes, need to be on the bottom so that the nut can clamp them properly on the bottom.

Any ideas? Electrical out on a Viper is scary when you can't find the manual latch because of the roll bar.... (haha)

[dave6666]

So you're driving along and the car just shuts off and you coast to the side of the road and then you can't get out because of total electrical failure? Is that what you said?

[AZTVR]

Well, I think that the quickest way to verify your theory is as follows. When the failure is occuring, measure the voltage
1) at the top of the stud itself. I am assuming that you are referring to the Positive stud on the Power Distribution Center = fuse/relay assembly in the engine compartment.
2) at the lug of the positive battery cable bolted to the stud
3) at one of the fuses in the PDC

Your theory would result in reading number 1 being lower than reading number 2, and reading 1 and 3 being the same.
A common issue is for someone to have turned the stud, trying to get the nut loose, and making the connection inside the PDC intermittent. That would result in reading 1 & 2 being the same and reading 3 being low. (If I am thinking straight this morning.)

[FlashFyre]

Well, I think that the quickest way to verify your theory is as follows. When the failure is occuring, measure the voltage
1) at the top of the stud itself. I am assuming that you are referring to the Positive stud on the Power Distribution Center = fuse/relay assembly in the engine compartment.
2) at the lug of the positive battery cable bolted to the stud
3) at one of the fuses in the PDC

Your theory would result in reading number 1 being lower than reading number 2, and reading 1 and 3 being the same.
A common issue is for someone to have turned the stud, trying to get the nut loose, and making the connection inside the PDC intermittent. That would result in reading 1 & 2 being the same and reading 3 being low. (If I am thinking straight this morning.)

You backed off the nut under the stud. When you hit a bump you lose the connection and lose power. Happened to me so I know. Take the whole thing apart and tighten the nut underneath and never touch that positive stud again.

[dave6666]

The factory stud works just fine as long as you know what you're doing. Just like all the things people say you're never supposed to touch on these cars. I've done them all and never had one of the horror stories happen.

[FlashFyre]

Here is my fix: https://www.viperalley.com/forum/vip...-terminal.html

[MrCreosote]

I've been quite concerned about "turning the stud." I disconnect everything each year when the car goes back into storage.

Since I restacked the eye terminals, I've had no "flame outs." Like I said, there is another small current add-on eye terminal that complicates things. (related to nitrous, halon and maybe VEC1 and rpm switches for nitrous.)

[daveg]

Is the stud firmly in place? When you rotate the nut does the stud turn at all? If you are not sure, index the nut and the stud next time you loosen and re-tighten to see.

[MrCreosote]

It's definitely solid. But knowing this, I'll be extra careful. (After doing this maybe 2 dozen times, I guess I might already be careful...)

[daveg]

I was told to be very careful with that stud by various Viper mavens.. One told me never loosen it without indexing it first.

[BLRDViper]

"I've been quite concerned about "turning the stud." I disconnect everything each year when the car goes back into storage."
What requirement are you trying to satisfy by disconnecting this when putting into storage?
If you are doing this on a routine basis you will be asking for problems.
If you absolutely have to disconnect the power I would consider a battery disconnect switch that is designed for this. Or disconnect a battery lead at the battery.
BLRD