More electrical trouble, need suggestions

[Si|v3r72]

Hello all. Some of you may recall I had some pretty big electrical problems last year with my 72 240. Something caused a total electrical meltdown, resulting in a burnt up wiring harness, dead battery, dead amp gauge, dead alternator, and bad voltage regulator (among other things). Well I got past all that and things had been going well until recently.

A few weeks ago, I was doing routine maintenance, and noticed that my battery was somewhat out of position. So I undid the hold-down, and refastened it, then moved on. Shortly after that, I started having trouble with the Ign fuse blowing. Upon replacement, I would lose the fuse shortly thereafter. So I opened the hood, and low and behold, there's the battery laying on it's side, with the ground wire ripped off, acid leaking out. I took care of this problem, replaced the battery hold-down (which obviously was crappy), refilled and charged the battery, and replaced the fuse. Well the fuse still blew. Now not only do I have a problem with a possible short somewhere, but I think the battery is dead too (I charged it and it died).

So my first question is, what is the recommended replacement battery for my stock 1972 240Z? My Z has no a/c, and the only extra electric device is a cd changer, so the power requirements aren't heavy.

Secondly, how do I find out why I keep blowing the Ign fuse? Unfortunately I'm pretty clueless about electrical stuff, but if I don't have to bring it back to the shop I'd rather not. They have enough of my money already.

Your assistance is greatly appreciated.

[EScanlon]

You need to check your fusible links, which are a kind of fuse placed in line on the electrical circuit.

Sounds as though you are getting a completed circuit to the ignition switch, just that it is causing a high amount of resistance, that indicates that the circuit is not being completed directly and therefore part of the original path is broken.

I hope you took the time to NEUTRALIZE the battery acid that spilled and not just hose it off the inner fender. This is important because you now have had an ACID spill in a prime rust area of the car.

2¢

Enrique

[2ManyZs]

Where have you been hiding Tom?

Like Enrique said, double check your fusible link, and also you might want to double check the ground on the battery cable as well, it may have been pulled loose, or the acid may have caused some corrosion already.

You definately need to do some clean up and neutralizing of any acid that spilled.

The battery is a Group 24 for a replacement.

Chloe at MidwestZ ought to have new hold downs and battery trays.

[gundee]

One thing I did and have seen a few others. You can buy the group24 battery with the + and - opposite of the origional.

That way the + terminal isn't 1/2" from your fender just waiting for the opportunity for a giant bang!

[Si|v3r72]

Hi Keith, nice to talk to you again. Been very busy for quite a while now, trying not to let my Z run my life but it's not easy . There's always something... I was just looking over the parts list at MidwestZ and I thought, "Damn, I could drop some serious cash here".

Thanks to you guys for some good advice. I'll try to get this straightened out this weekend. I need to finish by Sunday morning though, cuz Sunday afternoon has [sitting on my arse drinking beer and watching golf] written all over it.

[Bambikiller240]

Originally posted by greyghost

One thing I did and have seen a few others. You can buy the group24 battery with the + and - opposite of the origional.

That way the + terminal isn't 1/2" from your fender just waiting for the opportunity for a giant bang!

This would be a Group 24F battery and it is a great idea to use. Just have to make sure the battery cables will both reach to where they need to be with the reversed posts.

[EScanlon]

You can also buy those replacement rubber caps for your battery leads. They act as an insulating shroud to prevent that sudden shock from a bounce.

However, the BEST safeguard is to make sure that your battery tie down is solidly mounted and that the battery will NOT move in any direction.

2¢

Enrique

[Si|v3r72]

Update on battery situation:

I took the battery to Pep-Boys to have it tested. BTW this battery is an Energizer, Group 75/86DT, 700/875CCA. The battery tested fine, just drained, so they charged it and ok-ed it. While I waited for it to charge I checked out the group 24 batteries. I had the salesman measure the dimensions, and I was surprised to find it is even bigger than the one I have. So I took my battery home, made sure it was secure in the tray, installed terminal covers, and fired the car up. It ran fine, so I installed a new 20A fuse in the Ign slot, and sure enough it blew after a few minutes on the road.

My questions are:

1) How do I tell if the fusible link is good or bad? I looked at the one in line with the battery and had no idea what to look for. Apart from obvious defects like burns, or a broken piece, I couldn't see anything wrong.

2) Is this size/type of battery going to cause problems?

[gundee]

Tom

The fuse you are having a problem with is powered from the ign. switch. The fuse feeds the following items.

1. Volt regulator

2. Hazard sw.

3. Choke sw. and light

4. Oil pressure sw.

5. Fuel tank sending unit

6. Water temp. sender

If you have an automatic trans., it also serves kickdown sw. and solenoid.

Start looking at those itms.

[Si|v3r72]

Considering what my car's electrical system has been through, and the trouble I am having now, should I be considering replacing the dash harness altogether? And if so, how hard is a good one to locate? Does anyone have a good source for these?

[Ed]

Tom, sounds like you have a short somewhere. Start by inspecting all your ignition wires. Clean all connections with some sandpaper and use some dielectric grease. You need to be thorough and insure you don't have a short anywhere.

I can't remember this test so someone help. You should be able to connect a voltmeter to the battery or it's connecting wires to see if there is a drain or short. HELP????????????

[Si|v3r72]

now that you mention corrosion... when my battery had come out of the hold-down and was on it's side, battery acid leaked onto the starter. The bolts are now corroded and the starter looks like crap. Could that corroded hardware be the culprit?