Elec woes, crank, no start after running then parked.

[4spdragtop]

Hi all, while out for a test drive the other day, I went to store. 10 minutes later crank, but no start. Popped hood wiggled this n that(no tools with me). Disconnected and reconnected distributor connector and it fired up. Made it 5 minutes down the road and died again. This time, no start, but cranked and drained battery. Waddled home, grabbed Lori's car and boosted the cuda.
Sidenote carb(Eddy 1405) is doing what I think is a "lean surge". I changed start orange springs to pink(1 stage richer) and rod change to 1446 with surge still occurring and possibly contributing to the stalling. But I digress lol, back to electrical bs....
For ECU I am running the Standard Motor Products LX101, coil is SMP as well. Ballast resistor, not sure.
Could this INTERMITTENT crank, no start issue be due to "mismatched" parts?
I have Mopar orange ecu 4120505 if anyone knows #'s of components to match with it?
This is in our 67 cuda rebuilt 340.
Elec ignition, 70+ charging system.
Thanks
Steve

 

[MOPAROFFICIAL]

Bring a alligator clip jumper wire with you to jump the terminals on the ballast.
I believe you have an intermittent short or break in voltage to those wires or via the ballast itself.
A spark checker you use between the cap and one of the plug wires is a good one too.. or just pull a wire and, slide the boot back some and look for spark during crank while holding it an 1/4 from the plug.

 

[A56]

Hi all, while out for a test drive the other day, I went to store. 10 minutes later crank, but no start. Popped hood wiggled this n that(no tools with me). Disconnected and reconnected distributor connector and it fired up. Made it 5 minutes down the road and died again. This time, no start, but cranked and drained battery. Waddled home, grabbed Lori's car and boosted the cuda.
Sidenote carb(Eddy 1405) is doing what I think is a "lean surge". I changed start orange springs to pink(1 stage richer) and rod change to 1446 with surge still occurring and possibly contributing to the stalling. But I digress lol, back to electrical bs....
For ECU I am running the Standard Motor Products LX101, coil is SMP as well. Ballast resistor, not sure.
Could this INTERMITTENT crank, no start issue be due to "mismatched" parts?
I have Mopar orange ecu 4120505 if anyone knows #'s of components to match with it?
This is in our 67 cuda rebuilt 340.
Elec ignition, 70+ charging system.
Thanks
Steve

View attachment 1716278518

View attachment 1716278519

View attachment 1716278520

View attachment 1716278521

Stealthy looking motor.

 

[4spdragtop]

Thanks J, yep, I foolishly didn't bring "supplies" this time as I was staying in town.
For a quick spark check(on any wires) I usually use a timing light. I position it so I can see the flash(or no flash lol) from inside car. Frustrating/embarrassing as f**k. Lots of compliments while I have hood up looking like a fool.
Just stopped at parts store and bought a SMP/Blue Streak coil UC12(no specs of course), SMP Ballast resistor RU4 ordered, no specs lol. I'll chk SMP site for specs(not holding breath)
Travel kit includes
Spare br
Spare coil
Timing light
Spare ECU(coin flip?)
Voltage reg
Voltmeter
CAA lol

Bring a alligator clip jumper wire with you to jump the terminals on the ballast.
I believe you have an intermittent short or break in voltage to those wires or via the ballast itself.
A spark checker you use between the cap and one of the plug wires is a good one too.. or just pull a wire and, slide the boot back some and look for spark during crank while holding it an 1/4 from the plug.

 

[4spdragtop]

Thanks George...even more stealthy when it strands me....

Stealthy looking motor.

 

[67Dart273]

HI Steve. Always annoying, right? On the side of the road.
You need to set up so you can determine "if spark."

The wiggle the dist. connector may be a clue, or it may have just been happenchance. That connector is very vulnerable to corrosion, loose connection, so try and clean it. I'm pretty sure that a .177 rifle brush will get inside those connectors. AKA "BB caliber"

As suggested, I'd rig up a couple of jumper alligator leads, and a test gap so you can pull the coil wire, sub your test gap and test for spark. Rig a gap, jumper power to the coil+ jumper the starter relay, and look for spark.

Don't forget the old test---with either key on or power jumpered to coil, separate the dist pickup connector and take the engine bay harness end, and tap the bare terminal to a ground. Should make one blue snap spark at the coil each time. This will eliminate the dist. as a problem

As usual, wiggle test the system connectors and make certain the ECU is grounded.

AFter that it is a toss up. If the ballast is good, and as above you can jumper it temporarily, then it's a toss up. If you don't get spark with the "tap the connector" test, then it's either the coil or ECU probably

I just cannot TELL you how handy the "emergency" system I put together has been for stuff like troubleshooting and firing up / testing engines. 4 pin HEI modul, and old coil and a couple of alligator leads

 

[4spdragtop]

Thanks Del, much appreciated, yes extremely annoying. I knew there was a "tap test". Just forgot exactly "how"
I always tell myself to make a "check list" and laminate the f'r and put it in with the emergency kit.
Meant to add remote starter to kit as well, handy for cranking engine while under hood.
That "emerg " system u made, is it for troubleshooting or to "get u home"?
If I wasn't such a stupid purist I may just use the hidden HEI that u and @TrailBeast mention.
Gonna download 71 service manual to get oem specs for coil and br(hopefully)

HI Steve. Always annoying, right? On the side of the road.
You need to set up so you can determine "if spark."

The wiggle the dist. connector may be a clue, or it may have just been happenchance. That connector is very vulnerable to corrosion, loose connection, so try and clean it. I'm pretty sure that a .177 rifle brush will get inside those connectors. AKA "BB caliber"

As suggested, I'd rig up a couple of jumper alligator leads, and a test gap so you can pull the coil wire, sub your test gap and test for spark. Rig a gap, jumper power to the coil+ jumper the starter relay, and look for spark.

Don't forget the old test---with either key on or power jumpered to coil, separate the dist pickup connector and take the engine bay harness end, and tap the bare terminal to a ground. Should make one blue snap spark at the coil each time. This will eliminate the dist. as a problem

As usual, wiggle test the system connectors and make certain the ECU is grounded.

AFter that it is a toss up. If the ballast is good, and as above you can jumper it temporarily, then it's a toss up. If you don't get spark with the "tap the connector" test, then it's either the coil or ECU probably

I just cannot TELL you how handy the "emergency" system I put together has been for stuff like troubleshooting and firing up / testing engines. 4 pin HEI modul, and old coil and a couple of alligator leads

View attachment 1716278602

View attachment 1716278603

 

[Murray]

In no particular order the things that I would suspect for an intermittent problem would be- ECU, resistor, coil.

 

[4spdragtop]

Yep, makes sense.
I had to do some digging(google) to come up with SMP catalog. To be able to see what they list for my application.
I used a 72 Plymouth Duster with 340. I selected that app as I wanted something with electronic ign. No specs at all, altho all 3 SMP parts I'm using(LX101, UC12 and RU4). Whether they are "matched" or not, who knows lol.
I also downloaded a 72 Plymouth Service Manual to get elec ign oem specs for BR and any other related specs. Unfortunately no BR specs lol, but there are for 71?? But 71 isn't elec.ign...wtf.

In no particular order the things that I would suspect for an intermittent problem would be- ECU, resistor, coil.

 

[4spdragtop]

Here is link for SMP online catalog
eCatalog

 

[65wgn440]

I run a shop and use Standard products on a regular basis, and they damn sure ain't what they used to be. Failures NOT uncommon. Yeah, they came out recently with Blue Streak again, supposed to be "better". Keep in mind that Standard offers two series of products, and their lower line is junk, IMO. Lower line has an S at end of part number (or maybe a T, don't remember because I refuse to use them. Either way, just make sure part number does not end with a letter). If you buy from O'Reilly's, you can be sure it is top line, as they don't offer lower line.

 

[RustyRatRod]

Don't forget to check the firewall connector(s). They are always a source of contention. I JUST had a crank/no start condition with Vixen on the way home from Charles' house the other day. Got under the hood and no fire. It finally started and we got it home. I checked the firewall connectors and the top one (with all the power going through) had all the brass connectors covered in green corrosion. I cleaned them off good and applied dielectric grease (all that I had) and she's not done it since and we've driven her a good bit since then, too.

 

[340sFastback]

I recently had crank no start issue and from advice of others on this forum measured volts at coil while cranking. I had 8 volts. After cleaning firewall connectors, new ignition switch, new battery I ended up with 11 volts when cranking. But I believe primary issue was red battery wire in bulkhead connector had corrosion.

But through all the thrashing around I believe I left key in Run position engine off far too often and too long ended up with coil secondary resistance 1.5 kohms above spec and burned up Unilite module. Both were only a few weeks old. Right now car is up and running with a single point auto parts distributor and auto parts store coil.

Make sure ECU, engine, and voltage regulator well grounded. I verified my grounds via voltage drop test between the above and neg battery terminal vs ohm test which won't test under load and less reliable.

 

[4spdragtop]

So measured all coils I got and all resistors.
There are no oem specs(of course) that I found for 1972(elec ign). But I compared my measurements to 1971 (points ign) as at least those are posted.
For 1971, Coil Primary Res is 1.65-1.79 ohms. 2ndary is 9200-10700 ohms
The ballast resistor for 71 is 0.5-0.6 ohms.
Now to my measurements...
CURRENTLY IN CAR
BR(unknown brand) 0.6 ohms but somewhat erratic(goes up)...gonna source a replacement.
Coil(unknown brand) 1.5 ohms primary, 8.82 2ndary.
Used Mopar Performance #4876732 Coil, 1.0 ohms primary, 4.57K ohms 2ndary.
Used SMP/BS 1.4 ohms primary, 9.13K 2ndary.
New SMP/BS 1.4 ohms primary, 9.14K 2ndary.
Spare ballast resistor 1.6 ohms...too high.

Now with all that rambling, the RU19 apparently specs at 0.5-0.6 ohms, once I can source one(or another at similar specs) I'll order one.
To me, the current coil(cold) is specing out fine. Very comparable to 1971 oem specs.
The only coil that doesn't compare to specs is the Mopar Performance #4876732...it's got slightly lower primary and 1/2 the 2ndary ohms...would that mean more "spark" so to speak??
Next trip I will make sure to take my kit. I think the ballast is getting hot and increasing the resistance to the point of drastically reducing voltage. Make sense?
Once I come across this crank but no start I'll measure the BR before it gets a chance to cool down and see what the resistance is.
Still open to suggestions/ideas....
Thanks all.

 

[4spdragtop]

Thanks, yep some stuff ends with a T. Thanks for heads up.

I run a shop and use Standard products on a regular basis, and they damn sure ain't what they used to be. Failures NOT uncommon. Yeah, they came out recently with Blue Streak again, supposed to be "better". Keep in mind that Standard offers two series of products, and their lower line is junk, IMO. Lower line has an S at end of part number (or maybe a T, don't remember because I refuse to use them. Either way, just make sure part number does not end with a letter). If you buy from O'Reilly's, you can be sure it is top line, as they don't offer lower line.

 

[67Dart273]

The ballast is supposed to do exactly that. It is supposed to change resistance with current flow and help stabilize or average out current flow through the coil. They WILL run hot!!

 

[4spdragtop]

That makes sense, but what is the spec when hot?
It's incredible there are next to no specs when searching these damn things!
Here's a thread with good info/specs.
Excessive ballast resistor resistance?

The ballast is supposed to do exactly that. It is supposed to change resistance with current flow and help stabilize or average out current flow through the coil. They WILL run hot!!

 

[4spdragtop]

318 Ignition

 

[Bewy]

This type of problem is very difficult to fix because there can be so m any culprits.......
So, process of elimination.
This is what I would do: get a dash board lamp [ low wattage ]. Sit on top of the dash. Ground one side of it. Run a wire from the other lamp terminal to the coil [+] terminal. Drive around. If the engine quits but the lamp stays on, good chance it is the ECU. If the lamp goes out, you are losing supply voltage; you then move the wire to the incoming side of the bal res & repeat test.
If the dist has high mileage & uses vac adv, it can also be open cct pick up wire because the p/up wires flex with VA

 

[Kern Dog]

OP has me on IGNORE so maybe someone can relay the following....
I've dealt with this numerous times with my Charger. For years I dealt with months of reliable starting and the occasional crank-crank-crank with no spark. I took the bulkhead plugs off, cleaned them, packed them with dielectric grease and the problem hasn't come back.
I figured the issue was due to a poor connection somewhere but I was focused on the coil, ECM, distributor and ballast resistor wiring instead of the bulkhead plugs.

 

[340sFastback]

OP has me on IGNORE so maybe someone can relay the following....
I've dealt with this numerous times with my Charger. For years I dealt with months of reliable starting and the occasional crank-crank-crank with no spark. I took the bulkhead plugs off, cleaned them, packed them with dielectric grease and the problem hasn't come back.
I figured the issue was due to a poor connection somewhere but I was focused on the coil, ECM, distributor and ballast resistor wiring instead of the bulkhead plugs.

I believe same thing happened to me. But in process of thrashing scrambling around doing voltage drop.test, field current test ect way too much time spent with key in Run position engine off which resulted in Unilite module, coil, cap rotor getting damaged all of which were only few weeks old. So now that wiring/switches/connections all in top notch shape have to replace ignition parts that got messed up in the diagnosis process. In mean time car is up and running single point distributor and local auto parts store. Once cars been running, then shut down, I can turn key it starts so fast I don't even hear the starter.

 

[4spdragtop]

Was setting timing today in shop. Fired up great, idled nice. Started taking readings for timing and after 20 minutes of idle time, under hood tach went wonky(same thing last year with 273). So I checked a few things. Didn't touch anything(left key in run) 1.Chkd coil +ve to gnd with test light, and power there.
2.Disconnected BR and it ohm'd at 1.6.
3.Put timing light on coil wire leading to dist cap(no light/spark) when cranking. BUT light/spark when turning key off/on 95% of time.
4.Jumpered BR with it still connected, crank but no start.
5.Tap test with dist connector(harness side), spark every time.
6.Replaced ECU(SMP LX101) with used 4120505, no change.

Bad coil?

 

[jeff alder]

Good Afternoon Steve,
Not to make light of what happened to you as you know I am a big fan of your fish...but is there any way you could post a video of you "waddling" home please? We love pics and videos even more.
Best Regards and Thanks
Jeff

 

[4spdragtop]

Lol, thanks Jeff. I'm sure my next test drive will leave me stranded so there's a better chance of me waddling home than of me fixing the issue(s)!!

Fn thing, so replaced unknown in car coil(measured res after stall) 1.9 ohm primary and 2ndary 10.54K. It was pretty warm as expected, 75*C.
Replaced it with a Blue Stream UC12. Fired up right away but stalled after 30-45 seconds.

Good Afternoon Steve,
Not to make light of what happened to you as you know I am a big fan of your fish...but is there any way you could post a video of you "waddling" home please? We love pics and videos even more.
Best Regards and Thanks
Jeff

 

[jeff alder]

Lol, thanks Jeff. I'm sure my next test drive will leave me stranded so there's a better chance of me waddling home than of me fixing the issue(s)!!

Fn thing, so replaced unknown in car coil(measured res after stall) 1.9 ohm primary and 2ndary 10.54K. It was pretty warm as expected, 75*C.
Replaced it with a Blue Stream UC12. Fired up right away but stalled after 30-45 seconds.

All my cars still have points or dual points. Ill leave this one to the experts...which isn't me. I hope you find it quick Steve I know it's aggravating. Take a look at what happened to Kern dog. Loss of spark can be a tricky booger especially with conversions.