61 Electrics

[Richard G.]

Last time I drove my car, I threw a fan belt. She got pretty hot but I shut it off at home, it didn't stall. Anyway sometime later I decided I'd better see what I'd done to the car. Checked oil and it looks great- no water in the oil, so I'm hoping engine is OK. When I checked the battery, I noticed it has heaps of corrosion on the positive terminal of tar top. (I have been using a battery minder and I think it causes more trouble than good by spuing out battery acid or vapors). Anyway, I spent a day removing the battery,cleaning the battery, terminals, posts, battery isolator swich , battery bracket,etc.,etc.. I put it all together. 12.4 volts with a meter on the battery, from neg post to battery wire on regulator and from positive post to battery ground strap. Since installing battery isolation switch, when I screw down the switch I hear a Click and the clock starts ticking, interior lightworks etc. Here's the problem: Clean battery, power apparently going out, but no interior lights, no clock -I didn't try to start it-no point. On the junction block all I see is lights, horn, etc. Is there a main fuse somewhere in line ? Any suggestions what the problem might be. Checked Nolan Adams book, my Corvette restorer disk, and archives but couldn't find any tips. Sorry this is a bit long winded but, any help greatly appreciated. Richard 270hp 283

[Wayne P.]

Re: 61 Electrics

Eliminate the battery switch and see what happens. These are notorious for going bad.

[Joe R.]

Re: 61 Electrics

Richard,

I would clean the battery post again, along with the socket on the switch. There is no fuse in line so you must be loosing power at the battery terminal.

Try starting it.

Just a Grimlin trying to ruin your day. Step on the little bugger!

JR

[Jack H.]

Re: 61 Electrics

This (remove battery cutoff switch) is pretty good advice... The ones with the screw-in knob can wear due to insuficient screw-down torque allowing the contact points to flex & arc. When that happens, they lose their thin brass plating on the contact bar and start climbing in contact resistance...

The more expensive knife throw style switches have a LOT more surface contact area and you get a solid tactile feedback when the switch makes/breaks. Personally, I don't recommend using the cheaper 'green knob' switches as I've seen several episodes of failure with them from other club members.

Now, if removing the cut-off switch altogether doesn't provide relief, consider taking your car to a competent auto electric shop. There, they'll be able to roll out their wheel-up diagnostic cart and load test your battery.

As battery's age, internal resistance builds resulting is reduced cold cranking power. A battery can show good voltage but have an insufficient stored current profile to drive the starter motor...