Hei conversion troubleshooting

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Squareback alternators using an older mechanical VR with 1 field output must have one of the alternator fields grounded to the case/body/batt - however you want to wire it. The other will go to the points style VR. True electro-mechanical 68ish VR's will have 2 rods exposed on the back. If its flat with 2 straps, it an electronic retrofit.
"...You can use a dual field alternator in an single field (pre 1970) car by using a jumper on one field to ground, but you can't use a single field alternator on a dual field (1970 and up) car..."
 
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pishta said:
Squareback alternators using an older mechanical VR with 1 field output must have one of the alternator fields grounded to the case/body/batt - however you want to wire it. The other will go to the points style VR. True electro-mechanical 68ish VR's will have 2 rods exposed on the back. If its flat with 2 straps, it an electronic retrofit.
"...You can use a dual field alternator in an single field (pre 1970) car by using a jumper on one field to ground, but you can't use a single field alternator on a dual field (1970 and up) car..."
Click to expand...
The back of my VR has some ballast-resistor lookin coils running diagonally across it. So I'm assuming its the old-style. Looks pretty though, no corrosion looks brand new.

I'm a little confused on the alternator ID. My car is a '67. It is obviously not the original alternator. It has 2 FLD terminals, So it is a dual field, and I need to ground one of the fields? Which one, does it matter? The one that is not hooked up has an insultor around the terminal, not sure what for.
 
The 2 rods is a true old style electro-mechanical points type. The non insulated field is probably already grounded to case, easily detected with a continuity tester. The insulated terminal is the one that gets the regulator IN. There was final year (?) where the round backs got dual fields too.
 
pishta said:
The 2 rods is a true old style electro-mechanical points type. The non insulated field is probably already grounded to case, easily detected with a continuity tester. The insulated terminal is the one that gets the regulator IN. There was final year (?) where the round backs got dual fields too.
Click to expand...
Wow holy crap then my alternator has been hooked up wrong from the day I got it. No ground to either terminal and VR hooked to the wrong one.
 
there you go......

moparalt-pre70.gif


or true isolated field with electronic VR

altwir1.jpg
 
smokinnjokin said:
Wow holy crap then my alternator has been hooked up wrong from the day I got it. No ground to either terminal and VR hooked to the wrong one.
Click to expand...
HOLD IT AND READ CAREFULLY!!!!

The thing had been working, right? Then it was connected correctly. ONE FIELD TERMINAL MAY BE GROUNDED already by leaving the insulating washer out of the assembly. BE CAREFUL. If you hook the field wire up to the grounded terminal, you will fry the regulator and or the WIRING HARNESS!!!

Also some isolated field (they are not "dual" field) units are "hacked" by rebuilders. THE SIMPLE ANSWER

Up through 69, originally, all Mopar alternators were grounded by one bush. There was only one terminal to which a field wire could be connected.

After the isolated field units came out in '70, there were "hack" conversions by some rebuilders that can GET YOU INTO TROUBLE, and if people "convert" them themselves by leaving out the insulators AND leaving the connector terminal on there, YOU CREATE THE RISK of connecting the field to the wrong terminal. Some photos, standby.......

This thread:

Alternator Roundback . couple questions please.


Not sure when they went from round to squareback. About 73, 74 I think

We need a photo, why? Because some lazy rebuilders CONVERTED 69/ earlier alternators to "isolated field" That is the proper name.

If it is actually a "real" isolated field, the first ones came out in 70, with some rare "late 69" ones which I've never seen, except pictured on the internet. The earliest versions had THREE regulator terminals, which is why the 70/ later regulator connector is shaped the way it is

This one here (click the link, too large to post) seems to be an oddity. While it appears to be "factory" isolated field (dual field) it ALSO has a place (marked grd) for the 69 style grounded brush. I don't know if this is Chrysler, or aftermarket

http://www.urqualitysolutions.com/images/36-7019-3.jpg

Here's another "oddity", same or similar to above......two isolated brushes, and a place for a grounded brush. This one is set up for a grounded brush (on left) and is missing the second isolated brush (yellow circle)

index.php?action=dlattach;topic=95028.jpg


Below is what the definitive 1970 / later roundback isolated field should look like.......two isolated brushes, and no place to mount a ground brush

attachment.jpg


Below is the hated, hateful, POS "rebuilder" modified. This started out being a 69/ earlier with a grounded brush. Rebuilders drill the hole shown here at 12 O'clock for the second isolated brush. This one still has a grounded brush

128306-500-0.jpg


Why post all this? Why does it matter? BECAUSE IT CAN be dangerous. Some of these "came through" with a grounded AND isolated brush, or with what 'appears' to be two isolated brushes. If you hook the blue ign wire to the grounded brush, "smoke happens."

If you are lucky and get the blue ign hooked to the other one, you are faced with horried overcharging, as the alternator is at "full output.

ReportBookmark
 
On the two terminal "isolated field" units, the wiring does not matter. You can connect the field to either and the blue battery switched ignition to either. The trouble comes when one field is either perpusly shorted to ground.
 
There are several possibilities not in order

1...VR could be bad, not common on solid state but could certainly be true of the mechanical

2..Battery could have a problem, also rare

3...Ground path drop as I already addressed earlier

4.. Wiring harness drop as already addressed

If you have checked the ground drop, and if you have checked and eliminated the harness drop, then the next thing is a tossup. Either try a good know battery if you have one handy, or replace the VR

The bottom line is that the VR MUST see exact battery voltage. Harness drop and ground path drop are the usual suspects.
 
Did not realize the photo links were run together. I see nothing wrong with that hookup off hand I'd say regulator is next
 
Update:
Just installed my new distributor from Halifaxhops (ray) and wow what a difference. Car revs up cleanly through the range. There is a little rough spot around 1500-2k but I think that may just be because the carb needs some adjustment. Or it is possible that 15.5-16v is really pissing off my HEI module. Either way the engine is running 95% better with the new distributor.

As for the charging condition, I have ordered a new mechanical VR (standard ign products, they are cheap and come w/ a 1-year warranty). Car is consistently showing 15.5-16 volts at idle or higher rpm, at alternator output terminal, battery, VR terminal, and ignition module relay hot. So no voltage drop. Hopefully new VR fixes it, and I haven't fried my ignition module before I ever got to drive the car.
 
So no voltage drop.

I don't understand how you know this? How did you measure it in other words. Unless, by the way, you ordered "new old stock" Standard, it is likely Chinese and is likely electronic "in a mechanical case." The tip off is the two large resistors you mentioned. None of the electronic replacements have those. Not that is a bad thing. It's just that modern quality suffers
 
The new mechanical regulator looked to be good quality. Said made in USA on the back. Did not fix the problem. Steady 16-17v now and it smoked a bit when first hooked up. Again, unhooking field wire and voltage went back down to 13.5-14 (battery voltage from the overcharging condition).

I don't think there is significant harness drop, with a lead on both the ign terminal (blue wires) of the VR to the battery positive showed 0.3 volts. Separate multimeters hooked to both while running (only way I could do it hands free) showed voltage staying very close throughout running conditions as I diagnosed other stuff.

I also disconnected the field wire from both ends (to rule out problems in wiring harness) and ran a jumper from VR field terminal to alternator field terminal. No difference, still wants to charge 16+ volts.

Last night, when I put the new distributor in, the car was running good. Have changed nothing since then but the VR, and the car is back to running like ****. Rough idle, won't rev without backfiring. So I think its a safe bet the ignition module got fried with the overvoltage. This is very frustrating.
Next, I guess its time for a new battery and alternator.
 
The alternator will not cause overcharge, in this case. The grounded field units cannot "full field" themselves.

That .3V drop was it measured with ALL wiring hooked up "normal"? Might be time to rob the battery out ofyour DD and see if that makes a difference.
 
67Dart273 said:
There were "once upon a time" longer and shorter rotor contacts. I'm not sure that much would make a big difference if the rest of the system is right. Just FYI, "15 ish" volts is not correct. Didn't I post above how to check this?

Another thing you might check is for alternator AC ripple. With the car running and battery normalized, put your meter on AC volts and clip it to the alternator output stud. Recheck with lights or other loads turned on. You should read VERY little, maybe a few tenths of 1 volt

Did you ever try to run it with the alternator field disconnected?
Click to expand...

The longer rotor tip model is available from NAPA as Part #: ECH MO3000
 
The overcharging issue is fully resolved. I ran a ground strap directly from the new VR to the alternator. It is now showing steady 14-14.5 v in all modes.

Unfortunately, the car is still running like complete ****. Same problem I had originally. I tested the ignition module, passed 4 tests in a row. I have hang tested a brand new coil and that did nothing. The weird thing is sometimes the car decides to run right, revs up cleanly but won't do it every time. The condition is very intermittent which makes me think electrical. When I first put the new distributor in, it ran good that night but when i fired it up the next morning back to normal. No major temp variations, and it does it whether the engine is cold or warmed up. I am stumped.
 
I have tried literally everything to get this HEI to work. Going to put points back on tonight. Will see what happens.

During today's troubleshooting the distributor was getting really hot. Seemed more so than normal. At this point I have swapped distributors, coils, spark plugs, ignition modules, wiring harnesses, run all kinds of bypasses and jumpers, so I don't know what else to try. Its always the same. Starts and idles like a champ, sometimes I can rev it up cleanly with car in park but as soon as i put a load on it runs like garbage and backfires. Well at least the overcharging issue is fixed.
 
So i put the points back on. No ballast resistor anymore. So full voltage to coil. Car ran fine. Problem gone. I didn't even bother to gap the plugs back down, they are at 0.045" and I went ripping around the neighborhood like normal.

So here's the facts.
HEI was getting full voltage to the coil and module via a relay. Confirmed this during the bad running conditions that it showed full 14v at both places.
Tested the Ignition module this morning, 4x and passed all.

Tested another coil a couple days ago, but that was with the old distributor. Car ran badly with new coil. So it is possible that the coil is bad, and the jacked up phasing on the old distributor hid whatever improvement hanging a new coil made.

Electronic Distributor is a rebuild HalifaxHops unit with a custom curve. I experimented with different reluctor gaps, tried 0.005" to 0.012", no difference. I switched orange and black wires on the module, drastic difference the car would only run one way. So its not that.

Grounds are also something I have wondered about. My last setup was a huge ground wire from alternator to VR ground to ignition module. So they should have all been on the same ground plane. All sharing a stud on the intake manifold.

All told I'm about $400 in and still running the points. What now.
 
The hand drawn schematic you posted shows the orange wire to W but thats the incorrect position on the module.

Are your spark plug wires up to the task?



l
 
I'm about out of ideas except maybe try a few things

1...Post a photo? of the module mount, make sure it is flat, mounted and heat sinked

2...Just because the pickup polarity ran much better one way, does not mean you don't have rotor phasing problems, which I'd suspect

3....You should be able to disable the charging system by yanking off one field wire either at VR or alternator, and the car should run fine.

4....How long are the dist. pickup wires and are they twisted? Are the pickup wires run away from other high current or high voltage wiring, and cross at close to a 90 angle?

So far as a coil, I just used the stock Mopar coil on mine, ran fine.
 
Joe
Do you have another module to try? I have a tester for them if needed also. Stupid question can you bring it back to the oem mopar ecu just to give a starting point again?
 
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67Dart273 said:
I'm about out of ideas except maybe try a few things

1...Post a photo? of the module mount, make sure it is flat, mounted and heat sinked

2...Just because the pickup polarity ran much better one way, does not mean you don't have rotor phasing problems, which I'd suspect

3....You should be able to disable the charging system by yanking off one field wire either at VR or alternator, and the car should run fine.

4....How long are the dist. pickup wires and are they twisted? Are the pickup wires run away from other high current or high voltage wiring, and cross at close to a 90 angle?

So far as a coil, I just used the stock Mopar coil on mine, ran fine.
Click to expand...

2. I tried reversing wires, the car would only run with W hooked to orange. Drastic difference. Seems unlikely that I would have rotor phasing problems with both my chinese reman distributor, and my custom-curved rebuilt OEM distributor. They both did the exact same thing. Intermittent spark and backfiring at higher rpm. Regardless of timing setting, swinging all the way from 0btdc to 15. Car would respond as you expect to the timing changes, but they did nothing to change the intermittent run condition.

3. I will try this, but I don't understand how it would effect the ignition system. Tested the ignition control module feed wire and the coil feed wire, both were getting full voltage at idle and higher rpms. No dips or surges.

4. Pickup wires are as short as i could make them and reach. Picture posted. I had both distributors hooked up to the module this way, maybe thats my issue? Can't twist around the portion where the butt connectors are. There are no other wires around in the area, its the back right corner of the distributor behind the kickdown bracket. Closest thing is the wiring harness on the firewall.


halifaxhops said:
Joe
Do you have another module to try? I have a tester for them if needed also. Stupid question can you bring it back to the oem mopar ecu just to give a starting point again?
Click to expand...

I never had a mopar ecu, converted from points. I really wanted something 100% solid state, no ballast resistor. I tested the module yesterday morning 5x and it passed every time.
 
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Unhooking the alternator field will kill it's output, and IF it was inducing some type of ripple or spike due to a faulty diode or "other" problem, that will instantly tell you

That's a great lookin setup. Too bad you cannot get it to work.

HOWEVER I would still be for checking rotor phase. Actually CHECK it. You have likely searched by now, all you need is an old cap and cut an opening so you can see the no1 rotor contact, and of course your timing light

I must admit, this is one for the books.
 
How about running longer wires from the distributor to the module and twisting them? Maybe mount the module away from the dizzy
 
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