HEI Conversion Done still not starting

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Casaroonc

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Notes to my old problems under the heading "NO Spark at Coil"

BTW 75 Dart SE 225 Slant Six

I have done the HEI conversion per the instructions found here http://www.slantsix.org/forum/viewtopic.php?t=15779

I now have spark

But the car still won't start

Now granted when I was chasing down the problem Before I decided to switch over I found suspect wiring I even replaced the fuse box (some weird stuff going on)

the "New" Battery (put in the car buy the guy I bought it from) was a piece of crap

The Car Cranks fine. Has Gas (at the Carb) but wont start.

I did not change the plugs (I gapped them to .45), the wires, the Cap or Rotor (Both were new)

Any thoughts My wife is about over me spending all weekend trying to fix this.
 
First thing I'd try is to reverse the leads at the distributor connector. You can also check this with a timing light while cranking, if you have an old cap. Drill/ saw/ break the cap enough that you can see inside at the no1 tower and use the light to illuminate the hole. You should see by the light flash where the rotor is at the time of the spark. If in doubt, reverse the dist. pickup leads and see where it moves.

(This is known as "rotor phasing" and you can Google it. When you reverse the pickup, the AC wave coming out of the pickup triggers the HEI at a different point in time, thus offsetting the spark time from where the rotor is pointing)

Other than that, is the cam drive in good shape? Distributor drive gear OK? Timing correct?

How long has it been sitting/ how old is the fuel? Tried starting fluid? Any pops through the carb, tries to fire at all? How do the plugs look?

Also, ANY doubt about spark, your coil + and HEI + are now the same terminal. Make sure BOTH the dark blue "ignition run" and the brown "bypass" wire are tied together at that point. You can also "make double sure" by hotwiring with a clip lead from a battery connection directly to the coil+

I'm fairly certain this diagram is correct. NOTE which HEI terminal the male distributor connector is wired to

zu5qn8.jpg
 
I tried reversing the pickup leads. I can't find my timing light so I haven't had a chance to check that (I know thats a big one). I have not pulled the Distributer to know about the gears.

I bought the car two weeks ago & drove it home two hours. It ran a little rough but not bad. We drove it around the neighborhood some. That Saturday we took it to my shop (wood working) to clean it up & it wouldn't start. Finally discovered no spark at the coil.
I messed with that for a number of days & finally decided to bite the bullet & change over to HEI.

Fuel is new, & at the carb. I did not try starting fluid. No pops

I did not tie the brown wire to the + side of the coil I used a relay, so the brown wire goes to that.

I checked the spark with a tester.

& I did ground the HEI

From the sound of it it must be in the Distributer? As in timing or?

Also one other thing there was a small canister like 1" tall 1/2" diameter with a red wire attached to the old coil + I did not attach this to the new coil setup.
 
The can is the radio suppression capacitor (condenser.) You may or may not need it, depending, just listen to the radio on AM if you have one. You can buy "generic" suppression caps at any decent parts store.

I don't quite understand your description of the wiring and relay?

LET'S BE CLEAR..................

If for some reason you don not have the bypass circuit (brown, IGN2) hooked up, you won't have spark while cranking the engine WITH THE KEY, but you WILL have spark if you are jumpering the start relay, key in "run."
 
I had this problem.
What sort of coil are you using?
Most HEI setups need a good coil

I could only get mine running with a coil like below
CRN-730-0092_AT.jpg
 
67Dart273

"I don't quite understand your description of the wiring and relay?"

The conversion instructions suggested that I use a relay to ensure good power to the HEI

From the Instructions

"You'll want to add a power relay to guarantee full line voltage to the ignition module at all
times."

"#30 is your power input. Connect this via a 14ga wire to a good, solid source of line voltage. Good options for where to pick up this power feed include the battery positive terminal, alternator B+ terminal, large terminal on the starter relay, large terminal on the starter. Put a fuseholder in this wire as close as possible to your power takeoff point. You'll want a 15A fuse, and you'll want to carry spares.
#85 is your trigger ground. Run a 16ga wire from this one to any decent ground.
#86 is your trigger feed. This one needs a 16ga wire that's live when (and only when)
the ignition is switched on.
#87 is your power output. Connect this via a 14ga wire to the coil + and to the module's
power terminal."

So in this set up i connected #86 to the brown wire.

I did jump the Ballast Resistor but only one side (maybe the wrong side? My car has a dual Resistor) I checked at the relay (but not with the wire off the relay) & I had power at #86 with the switch on. That being said I still did not find out where my voltage drop is. I was only reading like 10.8 volts at the Resistor before the change over.

"The can is the radio suppression capacitor (condenser.) You may or may not need it"

I think this is attached to the top of the motor. It has one line attached to the alternator but nothing attached to the other blade. I looked all over for a wire without a home but didn't see one.

zanderzone


I switched the coil to an ACCEL 8140 super stock ignition coil


Thanks Everyone
 
It sounds like all is good except maybe the resistor. Measure the voltage, key in "run", engine off at the coi + terminal. You should have close to battery voltage. If you have low voltage, you bypassed the wrong side of the resistor.
 
Use a test light......
Turn the key on.... do you have power to both sides of the reisitor?
With the key on.... Do you have power to the + side of the coil?
If that is all good....Put the test light on the - side and crank the engine over.. Dose the bulb flash?
 
"I now have spark" means there's probably nothing the matter with your ignition system. I'm going to guess you've had the distributor out at least once, so you've probably checked and approved the condition of its drive pinion (or at least you've verified that the distributor is in fact turning when the engine is cranked), right?

Next up on the list: ignition timing. Very easy to mess it up on the slant-6. See here.
 
"I'm going to guess you've had the distributor out at least once, so you've probably checked and approved the condition of its drive pinion (or at least you've verified that the distributor is in fact turning when the engine is cranked), right?"

Actually, as lame as this sounds I have not run it with the cap off to see that it was turning & I have not pulled the Distributor to check the teeth. That being said I checked the spark at both the Coil wire & a spark plug wire. So if I getting spark at the plug wire it should be turning.

I haven't had a chance to check the timing yet.

I think I'm going to try Starting Fluid as well just to be sure it's not that.
 
Casaroonc said:
Actually, as lame as this sounds I have not run it with the cap off to see that it was turning & I have not pulled the Distributor to check the teeth.
Click to expand...

Oh! You probably should.

That being said I checked the spark at both the Coil wire & a spark plug wire. So if I getting spark at the plug wire it should be turning.
Click to expand...

Probably, unless you happened to check at the plug wire where the rotor is pointing.
 
IF THE distributor IS NOT turning, you won't have spark

Where I was going with checking voltage to the HEI OR jumpering power direct to the coil, is you may have LOW voltage and POOR spark.

Checking timing is a given
 
OK so it looks as though I DID do the conversion right. I got it to start yesterday with some starting fluid, but it would only run for a minute. I then discovered a leak at the base of the Carb.

So I will start a new thread with my questions regarding rebuilding the carb & vacuum lines. I don't have the time right now but I will call it "Carb& Vacuum line problems"

I would like to Thank all of you for your information so far. It really has been nice to be received into your group, & to be looked after by you all.
 
Hello all
I have a 74 Dart 318, been giving me trouble for about 3 years now,
finally about 5 months ago, I reset the timing by using just a vacumm gauge,
worked great, no more pinging or missing. then I did a stupid thing and uped the
RPM. well that set everthing backwards, I reset the RPM to where I had it but
it did not make a difference, car is not running good any longer. So I thought
I would switch to the HEI gm module, I did this on my 351c and it worked great
but in the mean time, on Sat, last I stopped for gas in the Dart, and she would not
restart. pushed her out of the way and went on to my business lunch, then came
back for the car and had it towed home. After doing some voltage checking
I had to Volts after the balast resistore... but since I was thinking of changing
to the HEI, I went ahead and did the swap.. I do have 12v really 10.7 at
coil + - and HVT. also at the G and W connections on the HEI module.
12v + - at the Dist cap tower.. but no volts at the spark plug.
I have a rebuilt Dist in the trunk so was going to swap it out just to see if
maybe the Dist pickup was bad, but it will not fit into the (hole).
I have read about connecting the old unused connectors for the balast resistor
together, Why? also something about connecting the (dark blue"run wire" and the
"brown" wire together) Why?
since that all goes to the old ecu .
Best

PS: So I just went out side and worked on the Dart, after reading some of your
posts I followed the info you gave.
I connected the brown wire to the (double Blue) and the car started.
I had by passed the MDS canister coil and used my Ford coil...
So I was excited and wired the MDS coil back into the loom, and the car would
not start. giving me the impession that the coil faild...
Those Ford coils (got mine at the wreaking yard) are great
So tomorrow I'll re time the engine, then head down to the wreaking yard for
a couple of extra coils...
but glad to have the dart running again... without that old ecu.
I paid $10.50 for my gm HEI off Ebay...
best
 
You connect the wires on both sides of the ballast together (usually brn & blu) to connect IGN1 & IGN2 circuits. That is because IGN1 gets power only in "run" position and IGN2 is powered only in "crank" position. By combining, you power the ignition in both "run" and "crank" w/ full 12 V, as HEI needs.

Next time, look at the GM 8-pin HEI & coil found in 85-95 trucks (cars to 93, termed "computer" or "small cap" distributor). It is simpler wiring since the module & coil plug together.
 
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