[steeltoedgloves]

Hi, I've ran into a dilema. I have a 70 Charger 500 SE w/ a 383 Mgnm. I kept having problems with my gauges pegging out then the next time I started my car, they wouldnt work. I'm not a mechanic nor an automotive electrician but I do have a 70 Charger/Coronet shop manual that described this problem. The automotive electrician I took the car to in the first time said that it was just a bad gauge so he replaced it with a working one. Well the car kept doing the same thing with the gauges & he said it couldnt be the limiter that they wouldnt work at all. Well after a couple of years of getting different items for my car as I dont drive it often, I finally decided to take on the task of replacing the voltage limiter & the printed circuitboard myself. I had the gauge cluster out of the car & had a guy that works on small motors & gears look at my tic toc tach which he couldnt get running. :frusty: .
By the way, the points & condensor system was converted to elec. ign.
I had all my wires marked & got the cluster back in with the new board & new vltg lmtr. Got everything hkd up & tried to start the car. Try to start the car & the brain box gets hot. It cranx, it starts to go into the go stage as long as the key is toward the start position but as soon as you put the ign. back to run, it seems like the engine loses its juice. My friend is a DIE-HARD MOPARMAN & an excellent mechanic. I drove it to his house before my wizardry & it remains there after my wizardry. He has cross tested everything he knows & says it has power everywhere it should. I tried the hdlts & hideaways -work, turnsgnls -works, 3 spd wiprs & wshr -works, brakelts -works, back up lts -works. try to start it & feel the back f the limiter & it is cool to the touch. Nothing smells hot. The Mopar buddy says that when you try to start the car, the voltage gauge shouldnt go backwards a little bit but mine does & did before my work.
The only thing we havent done is to take the strng-wheel apart & chk the wires in the column. ?

HELP !

 

[dana44]

Well welcome to the forum to start with. Second thing is to check the ballast resistor itself. I have a '68 Charger so know for a fact there isn't anything within the dash that can cause this with one exception, possible short to the amp gauge itself. The case of the gauge is metal, there is an almost thick cardboard insulator, and then the two wires, one from the battery and then out to the fuse block. If the isulation is bad it could cause a problem, but it usually shorts the whole electrical system out completely because it is a direct power from the battery (which is why the amp gauge registers when you turn on the headlights or open the doors). With that, check your ballast resistor. I say this because the almost starts until you take your hand off the start position it dies is 99 times out of a hundred this issue. I know how much fun the instrument panel is to remove, but you should have room to reach up from behind and see if swapping the old voltage limiter changes anything. If not, you did verify the printed circuit board was the same point for point, might be something there, but probably not, I think 68-70 was the same all the way (except outer cover material pattern).

There is one quick verification check that can be done with the ballast resistor and that is to run a wire between the two sides. If the car starts normal, do not not not let it run for more than one or two seconds, it will burn up the electronic ignition, but it can be used to verify it is bad.

 

[chuzz]

Dana, would running a jumper wire from the positive battery post to the positive post on the coil and jumping the starter solenoid start it like with the points style distributor. I lost a key to my Dads old 64 Dodge wagon once and started it that way. Got home before him and got my moms key and hustled up to the hardware store and had another key made before Dad got home from work. He never knew! LOL

 

[dana44]

Dana, would running a jumper wire from the positive battery post to the positive post on the coil and jumping the starter solenoid start it like with the points style distributor. I lost a key to my Dads old 64 Dodge wagon once and started it that way. Got home before him and got my moms key and hustled up to the hardware store and had another key made before Dad got home from work. He never knew! LOL

Good one!

 

[chuzz]

But, would that work for him with the electronic ignition he has on it? I'd hate to see him try that and fry something. I can't remember if I ever started a car with electronic ignition that way.

 

[dana44]

Which is why I said only a couple seconds to verify it does in fact run once the start position is disengaged. The Hall Effect can accept a short jump in voltage, for a couple seconds, but about the only way to check if it is indeed the ballast resistor.

I get what you are saying, that is a matter of jumping the engine, yes, but it won't bypass a bad ballast resistor. Running a jumper wire across it, turning the key to start then if it starts and runs when you let the key to run, if it does, turn it off quickly. This can verify the ballast resistor, the hall effect can handle the spike in voltage for a few seconds safely, so don't go driving it that way.

 

[chuzz]

Ahhh, thanks for the lesson, Dana. You're never too old to learn!

 

[dana44]

That goes both ways, I learn all the time.

 

[steeltoedgloves]

Hi again.
A day after I sent the ? to you, I remembered I tried to put a screw into a screw-hole in the steering column where one was missing & it acted as if the hole wasn't big enough so I backed it out, ???? I told my mopar mech. your suggestion of the amp meter being bad. He said that that could be but he wanted to try a few other things. I also told the Mopar mech that about the screw in the column but he doesnt believe that that is the case. He's just set on the idea that I crossed something putting it back together or the guy that chkd the clock in the t.t.tach probably screwed something up in there. I went ahead & bought a new ballast resistor since they dont break the bank & tried it but it didnt seem to help the situation.
But anyway.
We started trying the whole scenario of trying to start it again but the spark of different areas was just intermittent. One try, we would get spark & the next try, there would not. Then sometimes the spark wouldn't be as strong. Later on, he ran a wire direct from the batt to the coil with a jumper rig & bypassed something somewhere (????) & was able to get the car to run albeit, it ran ruff bcuz of the plugs being fouled now. He ran it for about 20 secs. The car wouldn't shut off with the ign so he would have to pull off the pos. batt cable. The tach didnt work ( idk if the other gauges wrkd) but the amp meter pegged out solid. Now I'm thinking about buying a new set of original style fact. gauges from a place on ebay @ $79. a pc.& possibly a new t.t.tach taking the advice from you to only run the motor 2 seconds at the most. What's another $700. It's only $$$$$ & you cant take it with you when you die anyway ! :runaway:
What's your opinion? Thanx again & thanx for your insight & suggestions of the problem.
I'll keep you posted on my soap opera !

 

[Bas Nossent]

I am sorry to interferr into this discussion and I am not pretending to know the answers to all your problems. The thing I do know is that the Mopar ignition is not the best / most reliable on the market. When it fits I usually put in a HEI with intergraded coil. These ignitions have a standard GM module in them that works fine. But, if a complete ignition doesn't fit, like in your big block, you can also use the original distributor and connect it up to a separate GM module with a 12 volt coil. It is not expensive and it will give you a much more reliable ignition.
Here is the link, there is a lot of discussion in this link but the drawing is correct.

http://www.forabodiesonly.com/mopar/showthread.php?p=1969863512

One more thing: when checking the distrubitor, just much feel a clear magnetic resistance 8x per 360 degree turn , when turning it by hand. If you don't, try to adjust the clearance between the hall sensor and the rotating part (whatever that's called), otherwise, use another distrubitor.

And another thing I forgot to say: make sure you cool the GM module. It will get pretty hot, quick. You can do that by fixing the module on a cooling plate with heat sink paste. This plate can dual as a ground connection.

 

[chuzz]

That rotating part is called the reluctor.

 

[dana44]

Bas DIY, that's fine except it is going into a pretty nice 70 Charger, not a Dart 4door, not the best looking thing under the hood. If the amp gauge is pegged, that's the place to start, something is grounded out completely, a pegged amp gauge usually would give the indication of a wire holding directly to ground and pulling as much juice as possible somewhere.

Hold off on the gauges for right now, they may be OK, but do pull the gauge cluster. Compare the old circuit board to the new one, make sure everything routes the same. It isn't a complicated circuit board, but something is wrong. Make sure all your wires look good, no melting of the sheathing and no melting to each other. The amp gauge itself has to have the insulating pad between the gauges and the nuts that hold it in place to isolate the power in and power out through the gauge, then directly over to the fuse block, it powers everything and is always hot. If this alone shorts or no insulating material is here, it can cook things quickly. This is a major thing that needs to be verified.

As far as the jumping to get her to run, it may be because of this power draw, consider it secondary right now, fix the short identified by the amp gauge first, because this is more than just a problem, it is dire to the life of the electrical system and all the wiring in the vehicle from front blinker lights to backup lights, literally.

Disconnect your battery, hopefully you did when the amp gauge was disconnected, given direct power from the battery and all that, and if not, do it this time.

The couple seconds is with the electronic ignition, not with points distributor, the jumper wire was not across the ballast resistor to get her to start but from the battery to the coil (bypasses the key circuit).

 

[steeltoedgloves]

Hey ---- Hi. I'm Lazy. Well that isn't my name of course but I took my car to a local car wiring expert.
He spent about 10 or more hours on tracing & tracking down the wires in the car & found that when my car was put back together in 1997 after the resto, the shop had not paid attention to the wires & placed the console wiring across the floor, laid the carpet then bolted the seat over the console light wiring causing an intermittent short until it decided to just go to open ground & cause the all of the silliness.

& as far as the Tac shooting to 80 rpm & then not working after that, a different local guy that is good at small electric A-C motors said to bring it by & he would work on the clock. When he put theTic-Toc-Tach back toghether, he put the spade bit on the back of the tach. Therefore, I fried my tach. -- Thanx Hot Pants Harry !
Thank goodness I bought another one. I placed the spade on the same screw bit on my new TTT but never hooked it up. The car wiring guy caught it & corrected it.
Thanx for the insight from [SIZE=18.399999618530273px] all of you. [/SIZE]