Ignition problem - No spark '74 Fury

josehf34

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I've been dealing with a problem in my '74 Fury. Is quite common that in cold start I got no spark, I mean I can't see spark in my spark plugs and engine doesn't start but if I mess with distributor and ignition coil wiring sometimes it start.


My car has a 360 Engine with an aftermarket ignition system, I've a HEI distributor with build-in ignition module and a Mallory ignition coild @58000V. This is the distributor: http://www.ebay.com/itm/Small-Block...ash=item2585ea6791:g:Q4kAAOSw-vlVi7xy&vxp=mtr


I already tested voltaje at ignition coil and I've 12.1V on "run" switch position and 12.8V on "start" switch position so I don't know what can be wrong. A time ago I had a problem with my voltage regulator I don't know if this maybe made some damage in the distributor's ignition module. Is there a way to test if the ignition module is fine?


Any idea will be appreciated :)
 
I've been dealing with a problem in my '74 Fury. Is quite common that in cold start I got no spark, I mean I can't see spark in my spark plugs and engine doesn't start but if I mess with distributor and ignition coil wiring sometimes it start.


My car has a 360 Engine with an aftermarket ignition system, I've a HEI distributor with build-in ignition module and a Mallory ignition coild @58000V. This is the distributor: http://www.ebay.com/itm/Small-Block...ash=item2585ea6791:g:Q4kAAOSw-vlVi7xy&vxp=mtr


I already tested voltaje at ignition coil and I've 12.1V on "run" switch position and 12.8V on "start" switch position so I don't know what can be wrong. A time ago I had a problem with my voltage regulator I don't know if this maybe made some damage in the distributor's ignition module. Is there a way to test if the ignition module is fine?


Any idea will be appreciated :)


Not to be a jerk about this... your ebay seller is crap. If you can provide a wiring schematic and own a quality DMM, I can talk you through some basic tests to identify a dead module, which doesn't match the starts sometimes symptom. Also could do a couple "pickup" or "crank sensor" tests... same part... lots of names, one of 4 basic designs. A coil test may be worthwhile, but specs would be tough to guess at.

Try summit, jegs, msd... see if you can find a similar system and post it's schematic and I will do what I can. Meanwhile go and buy a spark tester... there are 3 styles... the one that is a blinky light is much easier to use (I recommend, $5). the other style has an adjustable air gap and is useful to try to guesstimate the strength of spark... not super accurate at that but preferred by some. 3rd is a spark plug with a ground connection attached. You can cause damage if you provide too much resistance during spark testing and hurt the module, in rare cases the coil too. Using the existing spark plug, you would HAVE to make sure the threads are grounded (don't spark near the battery or fuel). By your write up I would be inclined to believe you may have had a flawed test method and might be going the wrong way on this. Recheck spark, find a schematic... if you still need help, I have lots of good tests you can do with a Quality DMM to help diagnose. $40ish (don't spend $500) for a quality DMM... must read mv DC (.01 volts) for automotive usefulness... should have a bar graph at the bottom for signals that change faster than the display can. Nice if it measures DC hertz, frequency and/or duty cycle... most people don't use accessories... so don't spend more thinking they will be useful... they can be... but if you cant think of an application you probably will never use them. 600v range usually means no millivolts, those are good for electricians, not 12v systems, yours will probably top at 200v. Sears has cheaper end of the spectrum that work good... parts store usually have crap, and cost more.
 
I have never installed an aftermarket "hi performance" electrical part in my life.
I have never had electrical problems because of what I installed.
You can follow the logic through any way you like.
 
I have no idea how that particular aftermarket setup is configured, but its become my opinion that HEI is not a good way to go after trying it for several years. Not because its a bad design, its actually very good and as people say its both more reliable and more powerful than the original (first to production) Mopar electronic ignition. But in 2015, they BOTH have the same problem: the original companies that made the power transistors and (in the case of HEI) control ICs have long ago gotten out of that business and sold the rights to a smaller company. Heck, Motorola (who made the MC3334 in HEI) doesn't even exist as a chip maker anymore, and its successor (Freescale) just got sold to NXP. And now that smaller company has sold the rights to some outfit in the 3rd world that cranks these decades-obsolete parts out for the (very small) replacement part market. I'm a EE by day and we face this issue all the time with power transistors for RF- sure you can still get the same MCxxxx or MRFxxxx part number that was state-of-the- art in the 70s, but today its made in china and when you measure the ACTUAL RF parameters in the lab, they suck rope compared to a working old stock transistor made by Motorola in the 70s thru early 90s (if you can find one). Buying a "Mopar" ignition module today, or an "HEI" replacement module today gets you a brick of mongolian mystery parts that works... sorta... and for a little while. I gave up on HEI and after many years of gritching about how "it doesn't really buy you any extra performance," I bought my first MSD ignition system. Wow. Problems gone. No, it really doesn't "perform" any better, but at least its made with current-world parts (yes, probably some made in China but at least to a higher standard because they're current front-line parts). So far its been reliable. I still have a working Mopar box on my '69 B-body, and I pray it outlives me because I went through so many on my C-body a few years ago.

So my advice, sadly, is to bite the bullet and go with one of the reputable aftermarket ignition systems, and use it with a stock Chrysler distributor.
 
I have never installed an aftermarket "hi performance" electrical part in my life.
I have never had electrical problems because of what I installed.
You can follow the logic through any way you like.

I agree with you Stan... I never had bad problems with Chrysler's early 70's electronic ignition... 4 and 5 pin modules and ballast resistors are cheap and fit in the glove box... issue solved. They weren't really that bad. The hybrid GM HEI coil in cap distributors summit or jegs sell might be good if you bumped compression... never on a stock engine though. Those put out so much energy some had .060/.080 plug gaps... begging for detonation there.
 
STANDARD MOTOR PARTS (the brand)
SMP-logo.png
has never let me down.
But, ohhhhhh, that's not sexy enough for people They want all them yellow and red crap they see on the engines at Dairy Queen on Saturday nights. And gotta gave anodized fake Aeroquip looking crap on there too.
 
Not to be a jerk about this... your ebay seller is crap. If you can provide a wiring schematic and own a quality DMM, I can talk you through some basic tests to identify a dead module, which doesn't match the starts sometimes symptom. Also could do a couple "pickup" or "crank sensor" tests... same part... lots of names, one of 4 basic designs. A coil test may be worthwhile, but specs would be tough to guess at.


Try summit, jegs, msd... see if you can find a similar system and post it's schematic and I will do what I can. Meanwhile go and buy a spark tester... there are 3 styles... the one that is a blinky light is much easier to use (I recommend, $5). the other style has an adjustable air gap and is useful to try to guesstimate the strength of spark... not super accurate at that but preferred by some. 3rd is a spark plug with a ground connection attached. You can cause damage if you provide too much resistance during spark testing and hurt the module, in rare cases the coil too. Using the existing spark plug, you would HAVE to make sure the threads are grounded (don't spark near the battery or fuel). By your write up I would be inclined to believe you may have had a flawed test method and might be going the wrong way on this. Recheck spark, find a schematic... if you still need help, I have lots of good tests you can do with a Quality DMM to help diagnose. $40ish (don't spend $500) for a quality DMM... must read mv DC (.01 volts) for automotive usefulness... should have a bar graph at the bottom for signals that change faster than the display can. Nice if it measures DC hertz, frequency and/or duty cycle... most people don't use accessories... so don't spend more thinking they will be useful... they can be... but if you cant think of an application you probably will never use them. 600v range usually means no millivolts, those are good for electricians, not 12v systems, yours will probably top at 200v. Sears has cheaper end of the spectrum that work good... parts store usually have crap, and cost more.


This distributor is pretty similar to my current distributor, I don't know if this can help http://www.summitracing.com/int/parts/pnx-d141700/overview/make/plymouth I have a digital multimeter so I can try to test the module




I have never installed an aftermarket "hi performance" electrical part in my life.
I have never had electrical problems because of what I installed.
You can follow the logic through any way you like.


I agree with you Stan... I never had bad problems with Chrysler's early 70's electronic ignition... 4 and 5 pin modules and ballast resistors are cheap and fit in the glove box... issue solved. They weren't really that bad. The hybrid GM HEI coil in cap distributors summit or jegs sell might be good if you bumped compression... never on a stock engine though. Those put out so much energy some had .060/.080 plug gaps... begging for detonation there.


I installed an aftermarket ignition system because the original distributor and ignition coil were in very bad shape when I bought the car so, why not try an upgrade with a HEI system. The new system worked very well until this problem appear now if my ignition module is gone I don't know if I should try a better ignition system from pertronix or mallory (I think isn't worth it to use a high performance ignition system like MSD in a daily driver car).


My stock 4 pin ignition module is still on the car but I don't know how easy is to find a mopar performance distributor or a new ignition box, I tried to search them on summitracing but looks like aren't available
 
STANDARD MOTOR PARTS (the brand)
SMP-logo.png
has never let me down.
But, ohhhhhh, that's not sexy enough for people They want all them yellow and red crap they see on the engines at Dairy Queen on Saturday nights. And gotta gave anodized fake Aeroquip looking crap on there too.

Then there's me... I've been meaning to paint the red MSD coil black so it looks stock (I bought it because at the time, the MSD blaster was a very well-made stock design coil, but now its made in China like everything else).
 
The SMP stuff has been made out of the country for years and they cranked out a hundred bazillion of them. But that means to me they got all the kinks out. :D
 
2013-01-16_042353_1[1].jpg

I found a pictorial diagram to help you... put one DMM lead on battery+ the other on coil-....while cranking watch for pulses at the bar graph at the bottom of your DMM display. If you get pulses... the transistor is switching. test the coil according to specs... ignition off, coil disconnected ohms between coil + and coil - should be around 1 ohm +/- .5 @70 degrees F... secondary side put one of the leads to the center tower should be Thousands of ohms. Specs are not exact... no clue what your running. I would guess if this is ok you have a different problem. buy the spark tester if unsure.

I can't do much else for you without meaningful information... 13 hours this sat by its self unanswered... I think its possible your the only one here with this system. Good luck.

2013-01-16_042353_1[1].jpg
 
View attachment 65619

I found a pictorial diagram to help you... put one DMM lead on battery+ the other on coil-....while cranking watch for pulses at the bar graph at the bottom of your DMM display. If you get pulses... the transistor is switching. test the coil according to specs... ignition off, coil disconnected ohms between coil + and coil - should be around 1 ohm +/- .5 @70 degrees F... secondary side put one of the leads to the center tower should be Thousands of ohms. Specs are not exact... no clue what your running. I would guess if this is ok you have a different problem. buy the spark tester if unsure.

I can't do much else for you without meaningful information... 13 hours this sat by its self unanswered... I think its possible your the only one here with this system. Good luck.

I tried this test and with engine cranking I got 25Hz reading (i had to test with hertz function because my multimeter doesn't has the pulses display). While the test i can see sparks on the ignition Coil dist connector so i plugged again the distributor wire and engine started fine.

According to this I think the distributor ignition module could be fine so i don't know where should I look for problems, the car isn't reliable if sometimes starts and sometimes no :(
 
I tried this test and with engine cranking I got 25Hz reading (i had to test with hertz function because my multimeter doesn't has the pulses display). While the test i can see sparks on the ignition Coil dist connector so i plugged again the distributor wire and engine started fine.

According to this I think the distributor ignition module could be fine so i don't know where should I look for problems, the car isn't reliable if sometimes starts and sometimes no :(


Very good... Hz still tells you there is a pulse... its a cheap quick test to narrow down no start dead module, not a very good module test... that would take a scope.

Since it runs try spraying water with a spray bottle all over the ignition components... watch for sparks and listen for snapping sounds. If voltage leaks you could have intermittent trouble based on weather conditions and condensation.

Before you dismantle anything and while running... do a few quick voltage drops:

DMM lead to coil + and other to battery +. recorded reading this drop should be .5volts or less IF you have a 12volt coil.

If you have a ballast resistor... Ballast switch side to battery + will be .5v and ballast coil side to coil + will be .5v the ballast itself will drop just under half of your voltage to allow 6volt factory coils to survive 12volt charging systems.

I don't want to start heroic measures to voltage drop the ground side of the coil. Because of the switching of the modules transistor it would take some doing to get meaningful results... just make sure all ground connections are in very good clean condition.

Do voltage drop the engine block with one lead and the battery - with the other... while cranking the engine with ignition disabled... if you drop more than .5volts clean up battery connections and ground connections at the block and retest... still too high you need a battery cable. Due to prior work and age ground cables get broken, corroded and left off during repairs. Typical symptom would be cranking speed or no crank... but once in a while the drop doesn't cause that problem but doesn't allow quite the right voltages elsewhere. It will ground through the engine mounts... just not very well.

the b+ at the starter and other lead at the battery while cranking will test positive cable .5v or less
the b+ at the alternator and other lead at battery b+ would test the alternator charging cable .5v or less
the case of the alternator and the battery - the test ground connection from alt to bat .5v or less

Voltage drops are the only accurate test for the condition of a wire or connection. If you do them enough to get comfortable you will be ahead of most of the folks who do this for a living. Where the starter attaches to the bell housing is its ground connection too... you would be surprised how often a little corrosion in there takes voltage away from the starter. With a schematic I can prove out the circuits of a car very quickly this way... always drop straight to the battery first, if you are .5v loss on the wire... stop testing it...it passed. when you lose too much voltage you have a poor connection or wire and need to start doing smaller tests between where you started and the battery until the problem is pinpointed. I have also used this test between rusty inner fenders and battery - to prove there wasn't enough metal connection for electricity to flow (add a ground strap)... the ground strap to the bulkhead goes to a transmission bell housing bolt and often gets forgotten at reassembly...

With lots of experience it usually takes longer to find a schematic and expose connectors than it does to get meaningful test results. The biggest trick is you can't open a circuit when doing a voltage drop so if you have a plastic connector you will need a needle or small paper clip to "backprobe" the connection. BE VERY CAREFUL NOT TO LET THE BACKPROBE SHORT TO ANYTHING ELSE.

Also double check your coil... if it says "12v" on it you may have the original ballast resistor still in the circuit and don't need it. See if you can find install directions for similar system... that may clear up your issue.

With no specs you could test your coils ohms and compare it to a replacement... not something I normally would approve of... if you can find a replacement on the shelf of a local parts store they should let you test it at the counter if its not sealed package. Bring your DMM and old part with you if you try this...gives the pretense of a sale, and temperature will greatly affect readings so don't get your too hot or cold. Similar coil with great differences on resistance might get me to buy the replacement and try it... its all guesswork at that point so don't get rid of the original and they wont take the replacement back.

Next time... go with a factory system. The old 4 and 5 pin systems were good and had tons of published diagnostics. A name brand aftermarket kit could work too... just watch reviews first and they should have diagnostic and installation help. Some A#$hole has shipping container of these with an investment of $5 or $10 per unit... no branding, no quality, no SEMA designation... forget it. Wife looked into a prototype toy for one of her clients as a promotional item... if you want to deal with 500,000... same price as 100 custom small run... all made in china.
 
Sorry... quick tap the brakes here... pull the plugs, keep them in order and look at the tips at the air gap. Make sure they are burning tan or grey on the insulation...black they are burning weak or too much fuel.... white they are burning way too hot or lean. Make sure they are factory part number champions... not something more expensive... and know that with your modified system the factory spark plug tune is out the window... you will be researching heat ranges and doing plug readings possibly for as long as you use this setup.
 
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