Electrical Issues: Clock running fast and hot fuses

[sexual_sushi]

Went to start the 240z (1973) one day after not driving it for a couple of weeks and the battery was flat. After charging it up I noticed the clock was running extremely fast, took about 15 minutes to do a full hour on the clock which it wasn't doing before. I have disconnected it but was wondering if this would be a problem with the clock or something else in the system?

 

I have also noticed the fuse box getting too hot to touch around the taillight fuse (bottom left corner). I think this is a common and possibly unrelated problem (fuse that the clock runs on doesn't seem to be too hot). This link http://datsunzgarage.com/probs/index.htm has a few fixes that include resoldering the wires to the fusebox and/or soldering a wire across one side of the fusebox. They also mention running a wire from the alternator to the +ve battery terminal so the charging system doesn't have to go through the fusebox. Any thoughts on these options? I suppose I should pull the fusebox out and check out the connections although I know Nigel put a brand new original Nissan center console and fusebox in when he restored the car.

 

Cheers

 

 

 

[Scoota G]

Start car Disco battery. Sounds like a collapsed cell.

[mtopxsecret6]

If its only when the car is running, charging regulator possibly, or a short in the electrical system causing a large current flow causing heat in fuse box and flattening the battery.

[Scottz]

Regulator.

When they go you can get full charge to the battery which cooks it. When you found the battery was flat, were the cells also dry or low level? Overcharging overheats the cells and evaporates the liquid very fast. You can usually smell the acid vapour. The unregulated charge speeds up the clock and cooks everything. I melted a fuse box cover once with the same problem. The clip in fuses and tacky wire terminals are the weakest contacts and create the most heat. Good solid contacts have less heat. (One method used to find bad connections is IR thermography. Bad contacts are hotter).

Run the engine and check output voltage from the regulator. From memory something like 14.4V.

If it is the alternator, you have the opposite problem of not getting enough charge. The car runs on battery for a few days and then goes flat.

If a cell or two drops in the battery, then it won't charge, and eventually flattens. This will not cause your clock to overspeed. Hydrometer test each cell.

Funny story - Couple of years ago RACQ had a spat of new commodores with flat batteries. It was the new alternators that auto cutout when the car is running for long periods. Problem was they didn't always cut back in when they were suppose to. Ha ha. So after a very long drive the travelling salesman parks his car, sleeps the night, and couldn't get a restart in the morning. A bit of trivia told to me by some nice RACQ mechanics near Sarina, while they were replacing the alternator in my old '92 Landcruiser.

 

Enjoy.

 

 

[Scottz]

Forgot to ask - Have you got alternator with built in regulator, or external regulator?

[sexual_sushi]

Thanks guys, great posts.

 

I'm 99% sure it is externally regulated.

 

Now that you mention it there was a smell in the engine bay that I couldn't put my finger on. Not sure if the battery was dry or not, the old man put it on charge while I was at work (every time he drives it he brakes something ).

 

Anyway I'll do some more testing/replacing and I'll post up my progress.

 

Cheers

[.]

You haven't been hiding your Ecstasy tablets in the Battery again have you

[sexual_sushi]

No just Viagra

[.]

Wouldn't Viagra cause your clock to stick on 5 to 12

[sexual_sushi]

Hahaha or maybe it would have 2 big hands?

[sexual_sushi]

A new Ingram 831223 Regulator (http://www.ingram.com.au/index.html) is $97 so I'm thinking I might just do the internal Bosch alternator upgrade and get a new battery while I'm at it.

 

Still have to do the tests to make sure I'm replacing the right parts but it makes sense from what I have read.

[PZG302]

Shaun get it tested properly before you do the upgrade so you are only replacing what needs to be replaced, otherwise it could get expensive.

 

The race car has just had the alternator die, and a new internally regulated Bosh alternator is $280, plus I have extras in modifying the wiring and kill switch to make it all work properly, ie pull the kill switch also kill the alternator.

 

$97 sounds like the better go for the regulator, unless you can source the alternator cheaply, or if you need a high output alternator. For the money you should get something that runs at about 80-80 amp instead of the standard 35 amp I had.

[garvice]

Pretty sure I have a 280zx alternator kicking around that your welcome to.

[sexual_sushi]

PZG where abouts did you get the alternator from? I got a price for Bosch BXD1242A (quoted for an 82 280zx) from Repco $330 and Bursons $359. From what I have read the wiring should be pretty easy, just a diode to cut it off. Is this the modifying you are talking about?

 

I might take you up on that offer Garvice, until I can afford a new one at least. Cheers mate

[garvice]

No worries, you know where it is (right next to that gearbox).

 

EDIT: Just had a look, I have a Hitachi one and a Mitsubishi one. The mitsubishi one needs a couple of case bolts, but other then that is fine.

 

Brad

[PZG302]

PZG where abouts did you get the alternator from? I got a price for Bosch BXD1242A (quoted for an 82 280zx) from Repco $330 and Bursons $359. From what I have read the wiring should be pretty easy, just a diode to cut it off. Is this the modifying you are talking about?

 

I might take you up on that offer Garvice, until I can afford a new one at least. Cheers mate

 

Shaun,

 

Wouldn't have a clue what the model number is, just that it was a Bosch alternator at about 80amp capacity and had the wiring redone to suit the internal regulator plus a heap of other work to the wiring, including renewing the wiring around the battery and a new isolator switch so when it was pulled the engine would cut as before with the standard 240 set up as well as a voltage warning light up in the dash for me to replace the ammeter. The bill wasn't cheap to get it all to work, but i won't have to look at that area of the car again for along time.

 

Jim Miliner did the work, and was also done so that when the car is rewired, hopefully over the new year depending on dollars, I won't have to rip out the new wiring just done.

 

If you can use what Garvice has offered then I would go with that as a cheap way out for the moment.