Technical New guy with odd electrical problem

Hi all, new guy but been lurking around for years.

I picked up a 1930 Model A with a sbc last year. The car had fuel injection and a lot of other issues. I have spent the last year completely replacing the entire electrical system with a speedway 22 circuit harness. Removed the fuel injection and with a blower and carb. Drove the car with no major issues(just some small fuel gremlins) for about 270miles. Thought it was all sorted out and went for a 70+mile drive, which it did great till the last 2 miles. Stumbled and thought it was running out of fuel(gauge needs adjusting) Pulled into the station,filled up and the car would not restart. After trying for 10-15min it fired and drove 2 miles home and died as I pulled into the garage and hasn't restarted. Found a burnt out pertronix unit, replaced it and no change. Now I noticed that as the car cranks, now the interior lights flash as it cranks. Also, with a test light on the coil, it flashes as it cranks as well. Is it supposed to have constant power as it cranks? Car turns over strong and smooth, just won't fire. The only other thing that happened was something got between the positive terminal and the block on the 1-wire alternator and shorted for about 5 seconds once at about 50miles on the odometer. The car ran great for about 200miles after without issue. No blown fuses or burnt wires. I have replaces the entire ignition system and still no fire. I am at a loss at how the interior lights are affected with the ignition. Anybody have any ideas? Sorry this was long, just trying to be detailed.

Hopefully get this thing back on the road and start posting cruises and such soon!

Thanks,
Mike

 

Hmm. Not sure why the light flashes as the engine turns over. Try running a jumper from the positive post of your battery to the + side of your coil and see if it starts. Don't leave that jumper hooked up. This is just to troubleshoot. Sounds like your +12v is oscillating instead of supplying a direct 12v.

 

The flashing lights tell me there is a bad connection somewhere.

Ben

 

Any ideas where to start? So far all connections between the battery and coil have been pulled apart to make sure there was continuity and no burned wires. Going to try the jumper next when I get back.

 

Are you getting spark at the plugs?
Remove a plug, connect wire, hold metal base of plug against a ground while helper cranks engine.
Spark?

 

Like firstinsteele said, you have a bad connection on the main power.

But do the interior lamps flash with them on, or do they flash with them off? If they flash and they are turned off, I'd be looking at a ground problem. If they only flash with them turned on, it could be power or ground. It is time for someone with an electrical background to do some voltage drop testing to pinpoint the problem. Or, you could just keep replacing things.

If we knew where you were located, someone on here might be able to help.

 

Had a weak spark last I checked. That's when I checked to coil and found the test light flashed when crankingon the coil. Replaced the coil, same results.

 

You say Replaced Ignition system,
What type using Now,
Protonix
Msd
Box or not
Points
Hei
Any ways what ever type running ,
Take make jumpers to Coil + & -
( positive and grounds)
Take the fuse panel out of the equation & ignition switch to test
Coil & distributor, ( Ignition )

Try starting , or check for spark @ a spark plug,
Jump off starter solenoid to crank ,
Get spark first then move to diagnosing the other issue,
It's possible bad coil or bad ignition whatever style you're using
Timing moved for No start up?

 

Take a jumper wire from the positive on the battery to the coil positive. See if it starts. If it starts then disconnect the wire while it is running and it should continue to run. If this is the case, the wire from the start position to the coil has a bad connection. It also could be a bad engine ground. To test that, use jumper cables and go from your negative terminal to the engine block. Don’t hook the positive to anything. One of those two tests should hopefully make it start.

 

Interior lights work as normal. Off with doors closed, on with doors open or with light switch, no flashing. As soon as I try cranking with the lights on, everything's flashing.

 

^^^^^
Sounds like Main Ground or positive cable issues, or battery volt drop @ cranking

 

Replaced with another pertronix unit. Have friends that have ran them for years without issue. Forgot to mention I thought I had a bad ignition switch(only part I didn't replace from the previous owners electrical) and that left the power on to burn up the pertronix. I have now replaced the ignition switch, coil, pertronix unit.

 

I'll check that as well. Battery is new and car cranks strong repeatedly

 

Since you say the starter is cranking strong, the problem is most likely in the feed wire to the electrical panel. It could be the main power to the ignition switch, but I don't know if that comes from the electrical panel or not. Again, using a voltmeter to test voltage drops will pinpoint the cause.

 

If the lights are flashing without being turned on, check the ground system first. A bad engine ground could allow power to back flow through other electrical systems that connect to it and have other grounded systems connected at remote locations. Such as engine gauges If the gauge shares a ground wire with the gauge light, the path could continue on until eventually reaching a hard ground point. Regular lights will come on regardless of which way the power flowers through them. Electronic Ignition systems are more particular about current flow. Too much amperage back flowing could melt a lot of wires.

 

I, like most, do not like throwing parts at a problem. This might be an exception. Don't worry about the non start until the main problem is located and fixed. Because of an experience I had a year ago, this is my advice. For what it is worth. If the battery cables are old with unknown history, bite the bullet and replace them. Clean the battery posts until shiny. Clean the grounding spot on the engine , or wherever the ground cable is fastened to, until it is shiny. If the NEW wiring harness has a dedicated ground, use a 6ga wire from there to the same end of the ground cable.
Once this problem is taken care of, tackle the ignition/starting problem if it still exist.
Too bad the FI was removed.

Ben

 

Just curious, what happens if you disconnect the distributor and turn it over?

 

Is the -ve of the battery large enough and is it secure and tight to the engine block, an equivalent size -ve should be connected from the engine block to the body/chassis. without this you will have all sorts of issues mostly caused by the return circuits trying to go through easier paths that may increase voltage drop. Re electronic ignitions and computers, they need 12v plus, 11.5v won't cut it under normal conditions,

 

Checked the main power connection on the starter. I think on those type of looms. Battery power lead is to starter terminal and main power comes off there. If it’s loose it’d explain the flashing lights as the starter turns.

 

Unfortunately life happens and I had something come up, I won't be able to get back to the car for a few days. I greatly appreciate all the responses and things to try. All will be looked at and attempted, even if I tried it once already. I will keep this updated as I try everything till it's taken care of.

Every electrical wire and component in the entire car are new as of 350 miles ago. Extra ground straps were added between the chassis/engine, engine/body, and chassis/body, all long before this issue arose. Any paint was removed before these were installed. I've always been one to have extra grounds on all my cars.

Originally I was going to keep the fuel injection for a year or two at least to drive and enjoy the car. After getting to look at everything previously installed, replacing everything and starting fresh was the cheaper, easier, quicker way to go. And blowers are cool and I just had one sitting around, haha.

Again, thank you all!

Mike

 

Since the harness is new and was good for a while, look at ever inch of the wiring, possibly something loose. I'd start with the ignition switch, if you don't know the pedigree, pick up a new one. Worst case you can save the old one for a spare.

 

Well, the car started and idled for a few minutes, then ivshut it off due to not having heat shielding around anything remotely close to the exhaust, but it ran. Voltage drop testing didn't reveal any issues. It seems the pertronix unit I purchased from the store was a return unit that was probably already burnt up. They warranted it and the new one seems to work so far. The interior lights still flash when cranking, but only with doors open. If the lights are off(doorsclosed) they remain off and don't flash. After looking over all the wiring I can get to without ripping up carpet, there are no loose wires or anything burned/melted and shorted. So still no change there. If all they do is flash when cranking, I can live with that for now but will continue to research it as I go. For now, as long as the car is drivable for the remainder of the season before it gets too cold, I will be happy.

If you have any other ideas about the flashing lights I'd love to hear it and will look into anything. If I don't find it later, I will make a new thread and post a video of what's going on.

I greatly appreciate all the help and suggestions from everyone!

 

Sounds good, hope you can get some miles on it

 

Sounds as if the starter is sucking all the power away, which I guess to an extent is normal? I'm wondering if the battery is upto the job (cca) and similarly the gauge of the battery leads.

Chris

 

Since ignition and interior lights are on separate circuits with an ignition switch separating them, look for what they have in common - electricity before before it gets that far. Try tightening all the nuts , bolts, and screws on the cables and wires that you can find. Wiggle things until something makes sense.

 

So the light is on because the door is open and when you crank it, it goes out? Or the light is out and it comes on when you crank it? Two very different problems to try and figure out.

 

Nothing to do with the flashing lights but is the coil matched to the petronix ?

 

I have ran into this a few times , master mechanics master disconnect switch . Leave the battery cable loose so you can easily remove it for storage . Always check for clean tight cables first .

 

I apologize in advance, this will be long. Sorry I haven't replied. I Never recieved notifications of other replies to the thread. So after the car started and idled the last time, I put it all back together, then it hasn't started since. After 2½ months, I finally had to put a jumpbox on it as it started to crank slowly. Cranking picked back up to normal, still no start. Pulled it all back apart and went over everything again and still found nothing. Out of other options a friend pulled the battery and had it tested. It failed. 1yr old and it's bad. Great, finally found an issue, replaced with new bat, no change. Still no voltage drop from any testing. Starter cranked strong again, faster than my 2003 truck. Out of other options went to the next device inline, the starter. Took it off and went to o'reillys and tested. Failed, bad starter, but still cranked strong. Ok, great, another bad piece. Replaced with new starter...same results. Still cranks the same with the starter as the old one. Lights still flash while cranking. Still haven't found any voltage drops at this point but still cleaned all the old grounds and added new ones.

Now at this point it's all torn back apart. I pulled the dist. cap to check the pertronix again and it's fine. I had new cap laying around from another project, and compared ohm reading from the outside coil contact to the center bump inside where the rotor tab contacts iinternally. I did this before when this all started and got the same ohm #s so I didn't replace the cap(distributorand cap was new 350miles ago). This time I got 84ohm on the used cap and 1ohm on the new. Reassembled with the new cap, put all the wiring back together and tried to start.... it starts and idles. Hallelujah problem is fixed right? No. Spent 4 hours putting the rest of the car back together, starting it 4-5 times and letting it idle for a minute or so during reassembly to make sure things are good, worked everytime without hesitation. Get it done and want to let it run a bit to make sure everything else is still working(gauges, elec fan, ect.) Car starts and idles for a little over 5-10min or so and alls good, got up to about 180° and just before the fan kicks on, starts idling and acting like it's running out of gas, had just enough time to verify the fuel pump is still running, pressure is good and fuel in the sight glasses, then it dies. It will not restart. Again, no spark. At this point, the entire ignition system is new. New battery, new starter, no voltage drop to be found in the system. It ran fine for 5-10min then died. I am at a complete loss. Talked to several mechanics and old school hot rodders, had some come look at it and try to help. No one has found anything and all have come up with the same ideas, even some of the same suggestions as here but all testing and replacing has lead to this. I don't know.

I have one person still thinking it's the coil. During this last runtime, it reached about 150° in 10min or less. It's mounted under the cowl, behind the dash. The units were flamethrower epoxy filled units for a v8. I have tried researching normal operating temperature for this but I have found everything from just over 100° to up to 200° is fine? I have mounted several coils under the dash of cars before without issues over the years. What is normal operating temperature for these coils? If it's too hot what could be causing it to heat up so much in a short time? It has been wired and verified correct to the pertronix installation instructions several times. And again it ran for 350miles before all this started without issue. I'm not against trying another coil, I just think the odds of having 2 bad coils fail so quickly is pretty low and unfortunately I have to pull the dash out and cowl off to get at it again.

If you made it this far, thank you. I am sorry again for the long post, I am just extremely frustrated and venting. If you guys have any further ideas or suggestions I am open to anything at this point.

Thank you!
Mike

 

@Basketcases
In pass I have used the S-W 22 Circuit in two vehicles with the battery mounted in the rear of the vehicle with no issues,
The kits I used where 8 & 10 years ago thoe ,, connector spades and butts were they good quality Name brand ? most of stuff sold at big box stores like Autozone O'Reilly's Advance Auto & NAPA brand to my opinion are junk Quality


You have came this far,
Make things Easy ( Easy to say )
Do you have 2 choices ,,
Do you or can you Borrow HEI
( will it fit ) it a 1 wire hook up & distributor is grounded,,,
Or a Points distributor?
Basically you will be bench testing except the engine in the car,,

disconnect your starter completely from wiring in side powering car , set a battery on the floor running ground cable from the battery to " 1 " of your starter mountain bolt , & a positive from the battery directly to the starter, get a remote starter button ,
Run an alligator clip long wire from the distributor positive ,so you can disconnect to the positive on the battery,
Alligator clamp/ roach clip,, if point you will need a ballast..
Disconnect the alternator power supply to car wiring ,make a jump lead go from the back of the alternator to the battery, the battery on the ground, try starting the car and see what happens, this way you have took everything out of the loop and made your own little test stand, & Go From here ,,

To Me , what you are Describing is a voltage drop /power supply (connections ) or ground!!
What size battery cable ground & Positive are you using and where and how far is the battery from the starter,?
cranking amps of battery and what size?
Not all batteries are created equal even that they look a like are the same group size...
What wire size is wire powering ignition switch, from stater solenoid & power fuel box / junction?

Lights dimming when Cranking !!
If Battery testing is too much get a universal it doesn't matter if it's a lawn more ignition switch /key or Remote hand held start button and OR make some test lead directly from the new switch to your existing starter,
Up plug old key switch just leave dangling,, have you ever Hot Wired a car, tractor that's basically what you will be doing. Also in all testing Voltage test meter required,


You are still at the point that you do not know if your distributor Protonix is good /Intermittent / defective or a issue WITH,
there has been many issues with these units even brand new out of the box,,,
When it comes to the coil I can tell you I have a 30 year old Acel big yellow coil & it is mounted on the tail shaft of my transmission under the car and I probably have over 20,000 miles with that set up with no issues with a
4 ish foot coil wire,, with a engine north of 650 hp,

Op there's several of us here that know this can be a headache /frustrations especially when maybe you're not that familiar with hot rods or vehicles wiring sometimes it's best to work backwards take everything out of the system like I mentioned having a battery on the Floor straight to the starter and then work from there Inward.
Backwards