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 Post subject: Valiant ignition issues
PostPosted: Thu May 17, 2018 8:00 pm 
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3 Deuce Webber

Joined: Sun Sep 11, 2005 6:18 am
Posts: 51
Location: Illinois
Car Model*: 69 Valiant
Hello all. I'm still working on ignition issues with the Valiant. I've checked/tightened and traced almost every electrical connector from the battery to the ignition coil. I found alot of little voltage drops but it's still breaking up/missing at high rpm. The main issue I have is that it's over-charging. It charges about 15.5V at idle and 16.3V above idle. The battery is good and cranks over fine. I have the Mopar Performance electronic ignition kit on it with the orange box. I swapped the box already with no change. I'm getting about 10V to the coil through the ballast with the engine revved up. I'm going to pick up a new voltage regulator for it tomorrow. That will hopefully solve the charging issue. I don't know if it will fix the ignition problem. As-is my MSD blaster coil is only putting out about 15KV per my adjustable test plug. It seems to me it should be putting out about 50KV. I don't remember what it used to put out back when it was running good. I don't think I ever tested it. I have an HEI test plug and tried it. It won't fire that one at all. I bypassed the ballast resistor and got it to put out about 25KV. It does have a nice blue spark, just not very strong.

Does anyone know if the over-voltage will cause the ignition to break up? I'll get the charging system lined out soon and post the results if anyone wants to know.

Thanks,

Joel


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PostPosted: Thu May 17, 2018 8:23 pm 
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Joined: Tue Oct 29, 2002 8:27 pm
Posts: 9523
Location: Salem, OR
Car Model*:
Quote:
I'm going to pick up a new voltage regulator for it tomorrow.


Are you using the old style buzz box/cheap electronic replacement or have you swapped over to the later square back alternator and a good quality dual field electronic
voltage regulator?


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PostPosted: Fri May 18, 2018 3:53 am 
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SL6 Racer & Moderator
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Joined: Sat Oct 19, 2002 12:06 pm
Posts: 6910
Location: Silver Springs, Fl.
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Make sure you check the bulkhead connector, for bad connections. I chased a intermittent misfire, for about (hate to say it) two years. turned out to be the connector.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 225 nitrous
64 Valiant Signet
64 Valiant 4dr 170


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PostPosted: Fri May 18, 2018 4:31 am 
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Turbo Slant 6
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Joined: Mon Jan 12, 2015 5:55 am
Posts: 631
Location: Brightwood, VA
Car Model*: 1965 Plymouth Belvedere I
FYI, over voltage can easily fry electronic devices. I would fix the over charging issue ASAP, then worry about the ignition problem.
I had a truck battery explode from an overcharging system.
-Matt

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-Matt
http://www.MattmansMopars.com
Strive for Excellence, not Perfection.


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PostPosted: Fri May 18, 2018 5:41 am 
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Joined: Mon Oct 21, 2002 11:08 am
Posts: 12596
Location: Blacksburg, VA
Car Model*:
I would also try a good stock coil to see if that has an effect.

Lou

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PostPosted: Fri May 18, 2018 8:55 am 
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3 Deuce Webber

Joined: Sun Sep 11, 2005 6:18 am
Posts: 51
Location: Illinois
Car Model*: 69 Valiant
Yes, I did check the bulkhead connectors. I cleaned and re-tightened all the female connectors at the bulkhead and at the ignition switch.
The ones on the ignition switch were pretty loose. I like to do a drag test on them after popping them out of the connector. Many years ago I had to replace the main battery feed terminals at the bulkhead because it melted the bulkhead connector slightly. I ended up drilling out the ignition feed to the voltage regulator and ignition coil yesterday in the bulkhead and replacing it with a new wire and terminals(It's in the hole next to the main battery feed and was melted slightly). It didn't help unfortunately. I thought if I have low voltage from the ignition switch to the voltage regulator(IGN 1) which is also the feed wire to the ballast resistor, it might be making it over-charge. No such luck though. I still have the original 1 field alternator on it. I've never upgraded because it's always worked just fine. As you can see, it will charge 15.25V at idle if it wants to. All my lights and accessories have always worked well at idle with it. I do have the 45A alternator on it instead of the 35A original one.

Joel


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PostPosted: Fri May 18, 2018 9:23 am 
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Joined: Tue Oct 29, 2002 8:27 pm
Posts: 9523
Location: Salem, OR
Car Model*:
Quote:
I still have the original 1 field alternator on it. I've never upgraded because it's always worked just fine.


There are many articles written about the need for the dual field alternator and EVR to provide stable voltage to the Mopar EI
(mopar EI modules are kind of finicky and will miss badly if they don't receive the correct voltage and amp requirement). If the
mopar Orange Box was made after about 2005 it may also be contributing to the miss issue as they have been outsourced to
another country and a fair amount of people have noted that they tend to burnout sooner than expected...

There have been a few members here that have tried to get by with the solid state version of the old buzz box only to find they are
made in China and you may end up buying 3 or 4 to get one that might work right (for a while). Upgrading to the EVR and buying
an Echlin or SMP unit would be an upgrade that would take the charging issue out of the equation.


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PostPosted: Fri May 18, 2018 11:13 am 
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Joined: Sat Oct 19, 2002 12:06 pm
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Location: Silver Springs, Fl.
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I'm not a fan of SMP (standard motor products). A lot of their stuff is garbage.

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Charrlie_S
65 Valiant 100 2dr post 170 turbo
66 Valiant Signet 225 nitrous
64 Valiant Signet
64 Valiant 4dr 170


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PostPosted: Sat May 19, 2018 2:44 am 
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EFI Slant 6
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Joined: Fri Sep 01, 2006 4:09 am
Posts: 391
Location: Tolland, Ct. 06084
Car Model*: 65 Dart, 225, 4 spd od, hyd clutch, BBD, 2 1/4 exh
" MSD blaster coil is only putting out about 15KV "

Secodary voltage in the coil wire this high should be checked twice.
It can be a measure of a high resistance in the secondary circuit.
Everything from coil wire resistance to spark plug gaps and parts in between are suspect.

In my case it turned out that the distributor cap to rotor gaps were too big resulting in:
1) ignition breaking down above idle
2) failed distributor cap center electrodes
3) HEI Ignition component rapid failures

Essentially a whole lot of arcing was happening in the distributor cap rather than at the spark plug.

My car now has 2 to 3 Kv in the coil wire after correcting the distributor cap and rotor gap and runs smoothly at any rpm with no other changes.

It was smart of you to check the coil wire voltage.....I think you are on to something!!

_________________
1965 Dart 110k, 225, Carter BBD Super Six, 2 1/4 single exh., sbp manual scarebird front disc, 7 1/4 rear 2.94 sure grip, 14 x 4.5 OEM wheels, 833 OD with hyd. throwout bearing, HEI, electric fan, ram air/heated air, Accusump. http://plymouthcarclub.com/


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PostPosted: Sat May 19, 2018 12:26 pm 
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3 Deuce Webber

Joined: Sun Sep 11, 2005 6:18 am
Posts: 51
Location: Illinois
Car Model*: 69 Valiant
Here's my update for today:
I added a ground wire from the voltage regulator mounting bolt to the master cylinder mounting bolt then added a nut on the mounting bolt on the back side of the firewall(the firewall threads are getting stripped out). I was showing about 200mV when I measured from the old voltage regulator mount to the engine block. This dropped the voltage down to 0V. No change in the charging voltage. Still 16.25V off idle.

I installed the new voltage regulator(Napa Echlin). My idle voltage was down to 13.5V and off idle was 14.1V. Right where it should be. I then checked the voltage at the ballast. I had 13.5V on the Battery side and 8.1V on the coil side, right where it should be. I double checked the coil output. I still had about 15KV coil output at the coil wire(which is the same way I tested before). I pulled the blaster coil off and checked the resistance. It had 0.8 ohm on the primary side and 4.7K ohm on the secondary side. That doesn't sound too bad. I had three OE mopar coils on hand to try. I still had the OE Mopar coil that came off the car and was still good plus two later model OE Mopar coils from fuel injected engines. I tested the ohms on all three and they were pretty close. They all measured about 1.8 ohms on the primary and 10.2K ohms secondary. I installed one of the newer ones and checked the coil output. It was about 20KV. Since it was a little better than what I had I took it for a test drive. No change in the misfire at all. It's been worse in 2nd and 3rd gear than in first. I put 6 more gallons of 93 octane in it at the gas station and tried again. This time I didn't notice the misfire as bad as I made a pull up to 5500 rpm. I made another run and it pulled good again to 5500 rpm.

I was running about 1/8 of a tank of fuel before adding the 6 gallons. I've run it that low in the past with no issues. At Mo-Kan I added 4 gallons of Sunoco 110 just to make sure I wasn't starving it for fuel. That made no difference. It idles alot better after putting the Sunoco 110 in it. I still think it's not quite right because it just quits accelerating at 5500 rpm. It used to pull to 6000 with no problem. I have a new fuel pump(mechanical) on it that makes 5PSI and puts out alot of volume(1/2 pint in less than 10 seconds). I"ll keep plugging away at it. I have a Carter electric pump I can put inline at the tank just for testing. Plus I'm going to try a different coil wire and check the inside of the distributor cap and rotor.

Thanks for everyone's suggestions.

Joel


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PostPosted: Sat May 19, 2018 6:32 pm 
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Supercharged

Joined: Thu May 12, 2005 11:50 pm
Posts: 5915
Location: So California
Car Model*: 64 Plymouth Valiant
I recently had a misfire. The cause was a spark plug that was internally shorting...….

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Ed
64 Valiant 225 / 904 / 42:1 manual steering / 9" drum brakes
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PostPosted: Wed May 23, 2018 7:47 am 
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3 Deuce Webber

Joined: Sun Sep 11, 2005 6:18 am
Posts: 51
Location: Illinois
Car Model*: 69 Valiant
I got a chance to do some more testing last night. I checked the resistance on the spark plugs and coil wire. The coil wire had 8.5k ohms. I checked a new wire I had that was the same brand and length. It had 4k ohms. I replaced it with a new one and also replaced 1 plug wire which was a little high. It didn't make any difference. At this point I was pretty aggravated. On a whim I put my old bbd carb back on to see what happens. The problem went away and it runs like it used to. I would have never guessed it was the carb.

Joel


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PostPosted: Wed May 23, 2018 10:12 am 
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EFI Slant 6
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Joined: Fri Sep 01, 2006 4:09 am
Posts: 391
Location: Tolland, Ct. 06084
Car Model*: 65 Dart, 225, 4 spd od, hyd clutch, BBD, 2 1/4 exh
Published Chart on coil wire resistance.....for 1 foot of wire:
ThunderVolt 50 = 40 Ohms
ThunderVolt 8.2 = 40 Ohms
StreeThunder = 500 Ohms
409 Pro Race = 350 Ohms
8mm Spiro Pro = 350 Ohms
8mm Pro Wire Resistor Core = 3,500 Ohms
Full Metal Jacket = 350 Ohms
Extreme Service = 350 Ohms
SST = 500 Ohms
8mm High Energy = 5,000 Ohms

So either your high resistance of 4500 ohm is for resistor core wires or ???

The Magnecor just checked at 120 ohm.
The Home made 8.5mm coil wire checked at 20 ohm.

_________________
1965 Dart 110k, 225, Carter BBD Super Six, 2 1/4 single exh., sbp manual scarebird front disc, 7 1/4 rear 2.94 sure grip, 14 x 4.5 OEM wheels, 833 OD with hyd. throwout bearing, HEI, electric fan, ram air/heated air, Accusump. http://plymouthcarclub.com/


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PostPosted: Wed May 23, 2018 4:11 pm 
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3 Deuce Webber

Joined: Sun Sep 11, 2005 6:18 am
Posts: 51
Location: Illinois
Car Model*: 69 Valiant
The wires I have are Belden high performance 8mm. If I remember correctly the resistance should be 5k ohm per foot. They are resistor type wire. I put my MSD blaster coil back on and it still runs good. I guess it was leaning out at high rpm with the Holley carb and causing it to misfire. It probably didn't have enough voltage to jump the gap when it leaned out. An ignition upgrade is in my future.


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PostPosted: Thu May 24, 2018 3:04 am 
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EFI Slant 6
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Joined: Fri Sep 01, 2006 4:09 am
Posts: 391
Location: Tolland, Ct. 06084
Car Model*: 65 Dart, 225, 4 spd od, hyd clutch, BBD, 2 1/4 exh
If you decide to upgrade ignition in steps consider building your own low resistance coil wire so that more sparking occurs at plug and less at the distributor cap/rotor interface:
https://www.ebay.com/itm/JEGS-Performan ... 2749.l2649

Re-measure your coil wire voltage after each step will confirm your progress......suggest you aim for lowest coil wire voltage to get best plug spark and best secondary ignition circuit reliability.

_________________
1965 Dart 110k, 225, Carter BBD Super Six, 2 1/4 single exh., sbp manual scarebird front disc, 7 1/4 rear 2.94 sure grip, 14 x 4.5 OEM wheels, 833 OD with hyd. throwout bearing, HEI, electric fan, ram air/heated air, Accusump. http://plymouthcarclub.com/


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