Battery exploded now truck won't run

[1lo620]

So driving home yesterday all of a sudden the battery in my truck exploded. Broke right in half. I assumed Texas heat had something to do with it. Or bad battery. So got new battery and now truck wont start. Turns over but won't start. Changed coil checked fuses..no luck. Any ideas? This is about the end of my datsun issues. Getting tired of working on them and getting them towed home. So lets hope it is a simple fix 

Or there may be a 79 custom 620 for sale. 

BTW it is a L18 with a petronix electronic ignition upgrade. If that matters

[banzai510(hainz)]

check for spark at the end of the center distributor wire to ground. 

I would have cheack this first before swapping parts.

 

 

washn out engine bay i battery acid all over paint if batter split in half.

 

also over charging will bulge a battery and ooze out and have white corrossion all ober the battery ends

 

 

theres that Patrol guy that lives in Texas maybe he will buy it

Edited June 24, 2021 by banzai510(hainz)

[thisismatt]

If I had to guess I would think overcharging, and pertronix maybe blew

[MikeRL411]

Exploding battery in Texas heat?  The usual cause of exploding batteries is frozen battery acid so obviously that does not apply here.  Overcharging would be my guess.

[banzai510(hainz)]

coils usually dont go bad

 

pertronix could pop but taking the center coil wire from distributor cap and near gorund and start the truck One should see spark

Edited June 25, 2021 by banzai510(hainz)

[datzenmike]

I hope you saved your old coil.

 

Half your fuses should be hot, the other 3 on the other side should be hot when ignition on. Check both sides of the fuse, should read something unless fuse no good. Don't trust looking, that's unreliable.

 

Does the horn work, the gas gauge read? Maybe just a fuse blown and coil is good.

 

 

[1lo620]

So my question is why is it all of a sudden over charging enough to blow a battery the way it does. I sure wish I still lived by you Hainz. Your the one who put the Damn petronix on in the first place. This crap doesn't make sense to me. Electrical drives me crazy. 

[thisismatt]

Voltage regulator failing in the worst way - over volting

[1lo620]

So I was checking out the truck and I came across this. Truly don't know what I am doing  here.  I am at a lost. I did check this by the fire wall not sure what it is. But I did notice one of the wires is broken.  I tried to test distributor not sure I did it right. And not a lot of Datsun people in San Antonio Tx. So I will probably end up taking it to a shop. It is my daily driver so I need it fixed. Any more Help will be appreciated. Never had an issue like this. 

[]2eDeYe]

10 hours ago, 1lo620 said:

 

Or there may be a 79 custom 620 for sale. 

 

 

 

In, thanks for the chance 😄

 

 

 

[]2eDeYe]

1 hour ago, 1lo620 said:

So I was checking out the truck and I came across this. Truly don't know what I am doing  here.  I am at a lost. I did check this by the fire wall not sure what it is. But I did notice one of the wires is broken.  I tried to test distributor not sure I did it right. And not a lot of Datsun people in San Antonio Tx. So I will probably end up taking it to a shop. It is my daily driver so I need it fixed. Any more Help will be appreciated. Never had an issue like this. 

 

 

That looks broken, Get a new one. 🙂

[1lo620]

1 hour ago, ]2eDeYe said:

 

 

That looks broken, Get a new one. 🙂

What the heck is it? And where can I get it at? Would that cause the truck to have the issue it is having.?

[datzenmike]

Voltage regulator.

NAPA or any auto supply.

[thisismatt]

Yup, get a new one. You can get a solid state version.

[1lo620]

So If I replace that voltage regulator will that solve the truck not starting issue. Or is it a deeper problem that was caused by the faulty regulator?

[datzenmike]

No telling right now, but it has to be replaced anyway.

[]2eDeYe]

You may have blown the fusible link during the explosion, but replace the faulty part then you can start testing.

 

Start off with seeing if the headlights work, they are any easy indicator of whether you are getting power. 

[banzai510(hainz)]

This is one reason to get those cig lighter volt meter or a volt meter in general in the truck.  I light the diodes type volt meters to see if one is chraging. one that goes above 15volts.. so when one drives one can see wht the voltage is while driving and with a load on to see how the alternator is doing loading down or OVER volting. like 16volts then one day battery cant take it.  with the volt meter one can catch this and fix it before seomthing happens. Most times its a weak alternator and battery dont charge and then car dont start.  as most go bad slowly over time. this case if wired it fryed one could see it right away and stop driving the vehicle.

 

Now I ask this ? was there a cover over this volt reg??? as it looks oxidized.I dont see you opening it up as you said you dont know what it is. So Im going to assume it was this way, like it had no cover over it. Most covers one has to bent the clips to get the cover off. Some one run this with out a cover? if no cover and egine bay was washed this most likely would have shorted out and thus draw to much current and pop the ground and or the fuse for the elelctrical ignition circut Im guessing.  Now if there was no cover shame on you. Pertronix I swear by them. As I still run them and have no proplems with them. Just dont take the ring off and leave the magnets stuck on the dist shaft and USE a Ballast resisitor with the stock coil they will last. Plus one can use the stock dist and not throw them away to just" I got to have a Matchbox" !!!!!!Even Matchboxes EI wear out. they are pushing 40years old. bushing spring. then the electronics coul still pop.. Most Pertronix or mallory Unitilite are destroyed by owners remoinv the ballst resisitors or changing to low ohm coils.

 

The Japan made volt regs mechanicals are good and I have had soem good luck with the Solid state ones . Have had them pop on me when I had a bad alternator and pop 2 in a row. then I went back to a Japan made mechanical one.

Napa sell a UA made mechanical one but I have over volt issues with these also in like 2 years so I wont buy them again

 

One you pope a ground wire the truck will want to find a ground elsewhere . Now in therey with a new battery even with the volt reg bad( or disconnect it it should still run off the batter for awhile till battery goes bad.  So check your spark. The pertronix may have popped. or maybe the ignition fuse to coil is popped. Get a volt meter and test at the ballast resisitor and at the coil +wire with key on. this is simple.

 

rememeber how fast I put that dist in . wasnt more than 15mins I swapped the point to Pertronix. Just neede the correct mount I think and bam it started right up.

 

when owning a 45year old Datsun have a newer car as a spare. Even I have been down 2 Datsuns at one time!!!!!!!Its a helpless feeling I dont like either.

Edited June 25, 2021 by banzai510(hainz)

[1lo620]

Ok so got a new voltage regulator. And it didn't start not surprised. So what is next. Remember go easy on me I am not the best mechanic and don't have and real fancy tools. And electronic crap is my enemy. So let me know where I need to go from here. Thanks guys. 

[thisismatt]

Did you check for spark off the center distributor wire like hainz suggested?

[1lo620]

So doesn't look like I have spark. So I am assuming my petronix is fried. I do have a matchbox distributor I can throw on and see if that works. Just don't know how to wire is up. And I looked for a diagram and I have seen several different variations. Any help there. 

And I hope I checked it right. Pulled the center distributor wire off the coil and held it to metal and see if it sparked? God I hate electronic crap. I just like doing the custom body stuff and leaving the engine stuff to people who know what they are doing. But don't have any mechanics that I know who work on datsuns in San Antonio. 

[thisismatt]

Other end. Spark is generated by the coil.

 

You have a mechanical fuel pump, right?

[datzenmike]

There is a single fusible link on the '77 so NOTHING would work, no lights, no horn, no ignition. The starter would turn the engine if you jumper the solenoid with a wrench... but no spark so it wouldn't start.

 

Does the ignition light come on? If yes then you have battery power into the truck. 

 

REPLACE the voltage regulator!!!!!!!! It's obviously fucked up and has to be done. Loss of spark may be a symptom of the blown regulator. This may even get your spark back. Fix the obvious things first.

[1lo620]

I replaced the voltage regulator. I have lights. No power from coil. I turned key on and checked with a testing lights on the positive side. No power. Have charge light when I turn key on. Horn never worked. 

[datzenmike]

If lights then fusible link is ok.

 

1/ Do the brake lights work? These will work with the ignition off.

 

2/ With key on, do the wipers work?

 

Need 1/ and 2/ to see if the ignition supply is working or the ignition switch is not.