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Posted by: no1uno Jan 2 2013, 08:36 PM

I'm trying to help my father get a project 914 started. It hasn't been started in a year. We tried to install a new battery over the weekend. First, we installed the positive terminal. When we went to install the negative terminal there was a larger than usual pop/spark and a sizzling sound. Within seconds, it began to smell and the battery cables themselves got very hot. It's as if there is high, ongoing load as soon as the negative connection is made. Any ideas? The fuses under dash look fine. The blue 25amp on engine relay board was blown. I replaced it but had the same problem. A bad ground, perhaps? What could draw so much power so quickly?

Thanks in advance for your advice.

Posted by: ednosnaws Jan 2 2013, 08:40 PM

QUOTE(no1uno @ Jan 2 2013, 06:36 PM)

Posted by: kg6dxn Jan 2 2013, 08:50 PM

Pull all the fuses and try again. Replace 1 fuse at a time until you find where the load is. If you still have spark without fuses, something is grounded that shouldn't be.

Posted by: no1uno Jan 2 2013, 09:13 PM

Ok. Thanks. I will try pulling all the fuses to see what i've got

Posted by: rfuerst911sc Jan 3 2013, 04:58 AM

A bad starter solenoid ? Headlight motors ? Wiper motors ? These are the only items I can think of that could draw enough current to heat up the battery cables. Be very careful a battery packs a LOT of explosive power !

Posted by: Spoke Jan 3 2013, 09:57 AM

If the battery cables got hot, its likely not anything in the fuse box. Something would have smoked long before the cables got hot.

Check wiring to the alternator and starter. Look for frayed wires.

Posted by: Cap'n Krusty Jan 3 2013, 11:20 AM

(1) Bad starter. I've seen it before.
(2) Bad alternator. Much less likely.
(3) A major short to ground in someplace other than the above.

You're pulling a LOT more amps than anything fused.

The Cap'n

Posted by: Nine_14 Jan 3 2013, 11:58 AM

QUOTE(Cap'n Krusty @ Jan 3 2013, 06:20 PM)

Posted by: damesandhotrods Jan 3 2013, 12:17 PM

A direct short to ground would result in smoke and burned wiring. A warm cable is a controlled path to ground. It sounds like your battery is seeing ground through something.

Posted by: Nine_14 Jan 3 2013, 01:50 PM

Disconnect the starter, (main connection) put all those wires together, by a 8mm scew and nut, make shure not having ground contact, connect your battery again and see what's happening.

If all other electric consumers are working fine, you need a new starter.

Posted by: Tom Jan 3 2013, 02:02 PM

Which wires got hot? Black large battery cables or red wires at positive battery connector that go to the wiring harness?
Tom

Posted by: 442nd914s Jan 3 2013, 05:08 PM

If its all original wiring, I would start by:
Disconnect both terminals at the battery. Remove battery
Continuity check as follows;
Negative terminal to a few ground points. This will verify a good ground terminal connection.
Disconnect all 2-3 (possibly more) red/accessory cables from the possitive terminals. You should only have the possitive terminal remaining. Disconnect terminals at the starter. Now all these disconnections, you can do a continuity check to ground. Check from ground to all positive wires, your results should be all open. Which ever wire gets u a "close/ohm” reading, THATS wire is shorted to ground. Follow it with a small grip to check for chaffing or possible strans protruding.
In my experiance with my 73, the positive terminal at the starter missing its cover and bent so tight it was approching disaster.
Wouldnt hurt to check your battery since you have the meter out. Possibly a bad cell or missed marked post. Most auto parts stores check batteries for free with a load on it. This is more acurate.

Good luck

Posted by: 442nd914s Jan 4 2013, 12:37 PM

I found this

http://www.pelicanparts.com/techarticles/mult_starter_diag/mult_starter_diag.htm

Hope it helps.

Posted by: no1uno Jan 4 2013, 12:55 PM

Thanks for all the help. I'll be there this weekend to give it a shot.

Posted by: Rusty Jan 5 2013, 07:48 PM

Any luck with your problem?

Is it possible that you hooked up the battery incorrectly, even for a moment, and shorted the alternator.

I did a dumbass thing when jumping my 914 a couple years ago... messed up the jumper cables. Popped the alternator and when I installed a replacement incorrectly, it warmed up the battery & cable because it was grounding out.