No spark while cranking - bad ignition switch?

[toddabney]

So here i am again, just when you think you've got all the bugs out.......so after lots of new stuff, ecu, ballast resister, new carb ,you know the story..... Now it has no spark while cranking but is hot when the key is turned back a hair.. So I am guessing that the ignition switch is worn out and has lost its spring. can I replace it with a generic one or is stock dodge the way to go? this place is great. Who would have ever thought?...So any ideas, todd

[DanielTBolger]

On my 72 Winnie, there's a black wire that goes to the + side of the start relay and back to the ignition switch, then the wire come off of the ignition switch and goes to the ballast resister on the coil side to give it a full 12 volts. This wire is only hot in the crank mode.

[denisondc]

      Either a new OEM type ignition switch, or any common replacement would work about as well.  Back then they were fairly standard; two ignition circuits (one for running, the other for starting), the accessory circuit, and the 'starter' function.  This works by grounding the wire, since the starter relay coil is connected to that 'grounding circuit at one of its terminals, and gets 12 volts to the other side of the coil, via the neutral safety switch.
   I found my 'spare' switch on ebay, for maybe $20.  Assuming yours is located inside the steering column, there is one at ebay now, (# 290276419888 ), but he is asking a lot for it.    Mine may have been used, though it came in an original dust covered box.   I liked having the same connector (8 terminals but only 6 wires).  The color coding was different than my old one, but it worked just the same.   You can also replace the switch with two s.p.s.t. throw toggle switches and one s.p.s.t. momentary switch for the starter function.
   Sometimes I have good luck with old switches by flushing the insides with an aerosol can of brake-cleaner;  (water and alcohol spray).   

[toddabney]

Hey gang, well today I pulled the ignition switch. I figured that it must be the switch because as I would turn the engine over nothing. The engine would turn over but no spark. The only way I could get a pop was to turn it over some then bring the key back just a hair. Then I would get something. So what I have done is, after I pulled the switch I put everything back together, accept the starter switch, which is out side the steering column. That way I can check out stuff as I turn the engine over. Using a volt meter I got 6-9 volts on ignition 1 (red wire), and ignition 2 (pink wire), while cranking it over. If it happens to start "bam" right up to 12-14  solid. So what wires need to be jumped to do what? (hope all this makes sense). I don't mind the "mad max" look when it comes to wiring. So do I need to jump the ignition 1 with a solid 12 volts? or just insert the coil wire down the carburetor? No, I try to not loose it over a machine but there are times ...I am hoping to drive to sunny southern California soon so I must get this worked out then I can go on to other problems...thank you all again. This is great. todd      God bless America

[DanielTBolger]

POSTIVE SIDE OF THE coil

[tiinytina]

I've had to replace the ignition switch in my Toyota Tacoma. Truck just wouldn't start or would after alot of jiggling etc... On my first truck way back my mechanic blamed it on the amount of keychains that were on my keys. The weight pulls on the key and causes the tumblers to wear in strange ways. When the old one was pulled it basically fell apart internally. Started haveing same issue in new truck (ok my truck is 11yrs old with 282K on it) last year (I have reduced key fobs to 1 and key number to house and vehicle. Replaced ignition switch no more problem. Only problem now is that my truck needs 2 keys to operate, one to get in one to start it.

Tina

[toddabney]

Easy as that? I thought that with all the electronic ignition stuff it would be more complex, but if its basic hotwire 101,hey I'm on it. Just a toggle or knife switch to put 12 volts on the positive side of the coil. Then when it starts you shut it off? we'll get'er thanks, todd

[toddabney]

so......do i need 12 volts to the + side of the coil? thank you all,todd

[toddabney]

Is this "the never ending story "or what? So today i was checking the volts while starting. It read, at the + side of the coil, 5 volts at rest key on. 8 volts while cranking it over  and drops to 5 or 6 volts  at idle.i talked to a guy today that said the way the ballast resister works is.....while turning it over it should read 12 + volts,then as it warms up it drops to 5 or 6 volts as not to "cook things". so....is my ballast resister on the fritz or is this guy just talking......it did start though, thank you all ,Todd

[The_Handier_Man1]

Ballest resistors are cheap.  It is good to have a spare with you anyway.  I say you buy another one and replace it, even though I don't like to just buy and replace parts without knowing they are bad.
Here is some info from others on how the ballst resistor works http://www.classicwinnebagos.org/index.php?option=com_smf&Itemid=43&topic=1062.msg1084#msg1084 , Les

[toddabney]

Les, thank you, thank you and thank you... That is just what I needed. That link was just the info I wanted. I replaced the ballast resister less than 200 miles ago, but that was probably at least a year ago as well. Maybe the dampness of the great northwest got to it.... Maybe someone makes a "extra heavy duty" ballast resister, (mine was like $10 bucks at Napa) or a person could make one. So I will try a new resister tomorrow and see what's up man! Again thank you for the link Les. Take care, todd

[jbmhotmail]

After a google search on "heavy duty ballast resistors" http://www.hot-spark.com/HS14BR.htm shows one and also lists napa part numbers. Check it out and see what you think.

[toddabney]

    well gang i think i foung the problem with my start ,no start problem.ever sence i have had this rig something seemed off.....like when the exaust pipes plug up.no defenut symtons,just not right. i explaned to a friend all that i have done to the rig only to have it not start at times! if i got it started fast ok,but if you let it flood ,forget it. he said that the battery could not have enough power.hmmm i told him it will crank over fine even with the light on. still he said i should have 600 cold amps minum.i got a megatron 1000,interstate. well that did it.with the old battery there was 4 or 5 volts at the coil while cranking it over.if you got lucky it would start and you were ok.but if not.....your stuck. so i install the new battery and it starts at 5 or 6 volts with the key on and up to 8 or 9 while cranking.....it has started every time since i got the new battery. i also replaced the 8 foot cable between the battery and the starter re-lay. so i would never have thought that a battery with enough power to turn your rig over even with lights on, that there wouldn't be  enough power for the coil to be hot!! so live and learn.if i would have got this battery a long time ago ,lots of time and $ would be saved. so now i hope we can hit the road. hope this all makes sence and is where it should be.take care,todd

[toddabney]

 >:(well ,well well!!!i still have a no spark problem......a while back i was heading out on our 2 outing ever,we go 3 miles down the road ,stop to get some berrys.i turn the rig off.......3 hours later i got it to start.......i drove home and it hasn't started since!!!! so there is 12 volts in both sides of the coil with the key on.but when i crank it no coil spark. i changed the coil out with a old one that worked a few years back.hey now that i wright it down it looks like a bad move.but tommorow i could replace it with one from my daily driver,as to know for sure.or am i getting cold.the coil i have for it now is a 50 buck outfit from napa,so it should work ...right?   but if you have power to the coil and it is good it should spark...right? any thoughts would be great.    .this spark thing has been my bane ever since i got it 2 years ago? thank you ,todd

[toddabney]

ps  would a new ingnition system be in order? or am i jumping the gun.thanks again, todd

[DaveVA78Chieftain]

Starting problems can reside either in the START (I2) or RUN (I1) circuit.
When the key is placed to the START position, 12 Volts is applied to the + side of the coil via the I2 position of the ignition switch.  This allows full battery voltage to be used by the coil.
When you move the key back to RUN, coil voltage comes via the Ballast Resistor (0.5 ohm leg) via the I1 ignition switch circuit.  This prevents high current to the coil during low engine RPMs.
The ECU is an amplifier that simply switches the current  ON/OFF to the coil based on the pickup signal from the distributor.
In your very post on this thread you said "Now it has no spark while cranking but is hot when the key is turned back a hair."  That can either be a bad ignition switch or the I2 wiring circuit.
The Dodge MH chassis manual discusses electronic ignition.  There is also an in depth Chrysler Master Technician Service Conference Series document about Chrysler Electronic Ignition at the Chrysler Imperial website  http://www.imperialclub.com/Repair/Lit/Master/312/index.htm

[toddabney]

hello dave and everyone else that spoke up.just tonight i went out and tried to fire it up.nada...there was 12 volts on both sides of the coil while cranking.i was holding the coil wire 1/8" away from a known ground.and nothing.  now there is no spark ever,there was spark in the 2nd circut (when you let go of the key while starting), but now nothing ......i havent put 100 miles on so many new parts,heck i haven't put 100 miles on it since i'v had it......going on 3 years now. it allways goes back to no spark.i hope this will turn out to be some oddball thing that i WILL stumble upon someday soon. > so again any more thoughts and thank you all for hanging in there with me,take care,todd

[toddabney]

 > > >:(well well well......So, today as a stab in the dark, I had the ECM tested even though it was only a year old......well some hope.  They tell me that the control module is bad.  Yes!!!  Something to go on.  So, I get a new one as mine is still under warranty, install it and ............nada...except now there is power to the 2nd stage (?)  of the ingnition system..... so, I am back to where I was... so long ago......I am really stumped.  Should i just give up and tow it to a shop....anyway?  "...and thats the rest of the story" todd i??

[DaveVA78Chieftain]

CAUTION
Connecting/Disconnecting the ECM module plug with power applied (Ignition switch ON) can damage the ecm module.
   
Have you downloaded (or have hardcopy) of the Dodge MH Service Manual from the members area?
If so, have you performed the electronic Ignition Tests (No Tester Available) starting on page 8-57 (pdf page 208)
Not sure what you mean by 2nd stage so, try to use the same terminology thats in the chassis manual so we can correctly relate to what you mean.
Your original problem was:

it has no spark while cranking but is hot when the key is turned back a hair

Is there 8-12 volts (higher is better) to ground (voltmeter black lead to ground)  at the + side of the coil (voltmeter red lead to + coil terminal) when key is in START position? (I2 wire from the ignition switch)  If not then the ignition switch is bad.
If there is good voltage with no spark, then either the coil, ecm, or distributor pickup is bad.
Is the 2 wire cable to the distributor connected?
Disconnect the distributor leads (at the small 2 wire connector) and measure the resistance across the distributor pickup leads.  Should be 350-550 ohms.
Is the ECM unit ground in good shape? (grounded via mounting bolts)
Is the Ballast resistor connected correctly?  (there are alignment pins on the connectors that engage indentations on the ballast resistor)
Are both resistors in the Ballast resistor good?  (1 side is 5.0 ohms [provides voltage to ECM pin 3; resistor feed by I1]; Other side is 0.5 ohms [Provides voltage to coil + when key is in RUN position;  resistor feed by I1])
Did you install the ROTOR back in the distributor?

There is a good animation of electronic ignition at
http://www.howstuffworks.com/ignition-system.htm
Unfortunantly the do not describe it's operation in the write up.
In electronic ignition, the distributor pickup signals the firing point of the plug (points open in the old days).  The distributor signal is sent to the ECM which is an amplifier.  The distributor signal turns the ecm amplifier off resulting in a collasp of the field in the coil which produces a spark at the sparkplug.

[toddabney]

well david thank you ,this will give me some homework to do.i do not know how to read ohms... yet but i have the testers.all i ever use is a fluke volt meter. i will do the tests you discrib and let you know. when i was speaking of the "2nd stage " i was refering to the 2 nd stage of the ingnition system.when the engine is turning over there is 1 power sourse to the coil,then when you let go of the key it goes to the 2nd power sourse to fire the coil.(2nd stage)  right?      well i do have 12 volts going to the coil while cranking.yet the coil wire held to a known ground  does nothing!!no spark at all. i even tried to hot wire the + of the coil with 12 volts and again no-go...in the past 100 miles i have replaced the coil,emc ,ballest resister (2 days ago)and the pick up coil.i get all my parts at napa.   i have grounded the emc unit and checked the conections on the dist. and the roter is in. how do you check if the balast resister is wired wrong. on mine those 4 wires seemed "well used"like they had been twisted around alot(i replaced the dammaged areas) making me wounder if they are in the right spots. i tried to imanage all the different ways you could plug them into the ballest resister, even though you put the pins where they seem fit right..(hope that makes sence) i will get my ohms figured out and let you know.this one is really kickin my a##.i have been turning wrenches for ni on 40 years now,and i am stumped.i will persiver and find this "missing link".this seems like it should be so straight foward,but i have learned that ANYTHING can go bad on a auto or a group of things can be wrong.troubleshooting is the hardest part of the job.i'll get it yet!!! i told my wife "this is like you baked your famos apple pie and it tastes like sh##.you know how to do it but for some unknown reason it turns out bad......sorry for ramblin on so much,i just needed to vent i guess.thanks again, i will   get it...todd

[DaveVA78Chieftain]

If you replaced the pickup coil inside the distributor, did you adjust the air gap?  Incorrect air gap will result in no signal to ecm so no fire
Dave

[toddabney]

yes .010 with brass feeler guage.i'm sure i will figure it out sooner or later. its just one of those things...thanks again,todd

[DaveVA78Chieftain]

Todd,
I have put together a detailed MOPAR Ignition discussion at http://www.classicwinnebagos.com/forum/index.php?topic=3424.0
Might help you figure your problem out.
Dave

[toddabney]

Hey Dave, I will check it out... but as of this moment I got it running last night!!!!   Yes, it's true!!  After all the hassling around it turns out the less than one year old pick up coil was bad???       I was having the same trouble with my neighbor kids Subaru brat.  no spark from coil.  Well, we checked everything.   I have a friend who is a Subaru mechanic.  I told my tale of woes, he told me how to test the pickup coil on the rig... hookup a test light to the negative side of the coil and turn it over.  If the pickup is good, you should have a bright, pulsating light.  Any thing else isn't good.  Well, the Subaru did nothing. 

I'll make this short.  On many 1982-1989 carbureted Subaru's have a common problem of losing the power to the electric choke.  So over the years, (8 different cars)  I would hook the choke up to the coil and never thought of which side to hook up to as it always worked... till this rig.  I hooked it up to the negative side of the coil, thus grounding the whole system?  I have been hooking up to the + side all this time, by Gods grace or dumb luck..so I unhooked the choke and it started.  Wow!  I hooked the choke to the + side on the neighbors rig and  ....all is well.  The brat purrs....   so live and learn.... anyway back to the Winne. 

Are these ignition systems so frail that replacing ballast resisters, EMC units and pick up coils are a common thing? if so what aftermarket system is "our "favorite?    So, sorry for being so long winded, but I had a lot to explain.  Happy trails,Todd and...  thanks again to all!!!!

[Oz]

Great to hear it, Todd!

It's not that the components for these early EI systems are "frail".  If we had a poll, I'm sure you'd find many members who have driven quite a few thousand miles without any problems.  I'm one of them.

Consider other possibilities.  A power surge that may have damaged a component, substandard manufacturing, flawed component materials...  by and large, these are rare, but, they do happen.

Many of these parts were used for over a decade(?).  Cheap to buy, easy to replace.  However, here's one of the Golden Rules of vintage RVing:

Carry spare ignition parts. If you do, it's likely you won't have any problems (Murphy's Law).  And, if you do, you'll be back on the road in a matter of minutes.