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post #1 of 33 Old 12-17-2007, 11:24 PM Thread Starter
biker250
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Frying ignition modules

'79 stock 4.2L. I keep fryin the stock ignition module. (The computer box that mounts to the inner fender) It works for a day or two then nothing. It'll fire up and immediately die. Anybody have any idea why this keeps happening??? Thanks for any help?


'79 CJ7 lifted 4" suspension, 3" body.....trying to remove enough rust so the body stays in one piece
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post #2 of 33 Old 12-17-2007, 11:51 PM
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Quote:
Originally Posted by biker250
'79 stock 4.2L. I keep fryin the stock ignition module. (The computer box that mounts to the inner fender) It works for a day or two then nothing. It'll fire up and immediately die. Anybody have any idea why this keeps happening??? Thanks for any help?
It happens because everything in this country is 'Discount' now, instead of quality...

The discount stores get modules made in Korea, China, South Africa, ect, and they won't live.

A factory quality module is hard to find, and when you do, it's going to run $80 or more.

This is a 'Quick Fix' you can do for about $20,
http://www.junkyardgenius.com/ignition/jeep/HEI01.html

Use a bone yard GM factory module if you can find one!
The rest of the distributor is crap, but the module does serve a purpose for use 'Jeepers'...

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post #3 of 33 Old 12-18-2007, 12:19 AM
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I had the exact same problem yet a bit more frustrating, the modules would last about 45 seconds... then the jeep would start and immediately die

I had a TFI setup installed with an aftermarket coil, took me 16 modules before I replaced the plug wires, cap, rotor, and coil out of pure frustration. These parts were all less than 3 months old.

Since then it has been running great on the 17th module for a few months and It seems to be fixed.

The problem isn't cheap parts, I am an Autozone manager and went through our Duralast modules lasted about 45 seconds while the masterpro (I think that is the brand) from oreilly's and a borg warner unit lasted only a very few seconds. Not saying our parts are better, Borg warner parts are top notch, but hey... I am just speaking from experience. I will agree that a select few of the parts we sell are junk.
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post #4 of 33 Old 12-18-2007, 01:43 AM
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I stay out of the 'Auto Jerks Sores' ... And no, I didn't misspell 'Store'...
When at all possible.

The Same module you sell is in a GP Sorensen box at Advanced Auto, a different box at Pep Boys...

I've gutted a BUNCH of them lately, and they are all made in the same three countries, Korea, South Africa, and China.
China and South Africa are a dead heat for the most failures!

Interesting enough, the $40 module at NAPA is the same also. It says 'ECHLIN' and 'Hecto en Mexico', but when you gut it, you will find the 'Made in South Africa' inside on the board or on the components on the board...

The only 'Good' modules I've been able to find are from Summit, and they won't tell me where they come from.
(Smart move! I'd spread it all over the internet like jelly on a southern biscuit!)

I don't see how anyone can guarantee their products with the amount of piracy, repackaging, and knockoffs there are, and if you buy anything out of the country, it's just got to be twice as worse!

If you can't trace it to the manufacturer, then to me it's directly suspect.
You can't believe anything you read on a box anymore!

Anyway, since you are a manager at AutoZone, can you get me the wells part number for the Ford harness resistor wire? 1.35 Ohm for Ford products from '75 to '84?

It's like wells 799, but I can't remember exactly what it is, and I've got people asking about it again on another forum...

Thanks man!
----------------------------

UPDATE

Never mind, it's Wells p/n F799.
Couldn't turn it up as 'Wells 799, but I found an old web page I made that has the part number on it.

Thanks anyway!

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post #5 of 33 Old 12-18-2007, 02:08 AM
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Quote:
Originally Posted by scrible
I had the exact same problem yet a bit more frustrating, the modules would last about 45 seconds... then the jeep would start and immediately die

I had a TFI setup installed with an aftermarket coil, took me 16 modules before I replaced the plug wires, cap, rotor, and coil out of pure frustration. These parts were all less than 3 months old.

Since then it has been running great on the 17th module for a few months and It seems to be fixed.
I can probably tell you why your cheap modules were failing...

Did you reset the timing after you installed the cap and plug wires?

If so you probably gave the ignition module a ground again.
One of the only weaknesses the Motorcraft ignition system has is it ground through the distributor.

Aluminum is a horrible conductor, especially when it comes to DC current.
Add in 20+ years of engine oil vapor varnish/enamel on the distributor stem,
(Varnish is used as insulator on a lot of types of wire!)
Moving distributor gears that may, or may not, be getting a ground,
AND,
Add in the fact that the ENTIRE primary side of the ignition system grounds through that distributor housing,

You just have a recipe for starving that module to death for ground!

Moving it around a little, like setting timing, or just loosening up the distributor hold down clamp and re-tightening it like you were GOING to adjust the timing...
Will sometimes be enough to get the primary ignition ground working again...

My suggestion is to run a dedicated ground wire from your negative battery terminal.
Stop at the head(s) and use a brass bolt, and an internal star washer to ground the heads so the secondary (High voltage) has a good ground, then continue on over to the ignition module.
Splice into the 'Black' wire of the module and give it a dedicated ground...

This should give your module a fighting chance (if it's not total crap to start with)...

I also run the dedicated ground wire from battery to headlights, then over to the ignition some times, which ever is handier.

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post #6 of 33 Old 12-18-2007, 07:51 AM
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Is there any ground in the case of the Dura Spark?????
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post #7 of 33 Old 12-18-2007, 09:06 AM Thread Starter
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Quote:
Did you reset the timing after you installed the cap and plug wires?

No, I have not reset the timing. On a side note, it's a brand new distributor, dist. cap, rotor, plugs, wires, & ignition module. (Been through 3 ignition modules now....all toasting)




Quote:
Moving it around a little, like setting timing, or just loosening up the distributor hold down clamp and re-tightening it like you were GOING to adjust the timing...
Will sometimes be enough to get the primary ignition ground working again...

Does this suggest that the ignition module is not "BAD" but rather just lost it's ground???






Quote:
My suggestion is to run a dedicated ground wire from your negative battery terminal.
Stop at the head(s) and use a brass bolt, and an internal star washer to ground the heads so the secondary (High voltage) has a good ground, then continue on over to the ignition module.
Splice into the 'Black' wire of the module and give it a dedicated ground...



How confident are you that this is the problem and not something else that would require me to go with the GM HEI ignition module? I would prefer to not get into doing all that swapping of parts right now...I would like to keep the ignition stock until I decide for sure what I want to do with the motor. Thanks.

'79 CJ7 lifted 4" suspension, 3" body.....trying to remove enough rust so the body stays in one piece
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post #8 of 33 Old 12-18-2007, 10:09 AM
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Bad grounds can cause a variety of problems.
Aluminum is the best conductor of electricity after silver and copper, however it is prone to surface oxidation (the oxidation is a poor conductor). Aluminum terminals in distributor caps should be avoided at all cost as the terminals oxidize and greatly weakens the spark (brass terminals will last nearly the life of the vehicle)
Adding grounds is cheap insurance and is easy. Brass bolts are unnecessary (IMO), Use stainless when bolting to aluminum as it will resist the galvanic corrosion that will happen to dissimilar metals in the presence of water. (verify the block grounds and clean the distributor hold down it should make good contact with the block and distributor, if it (and the distributor are) clean and the chassis/block/battery grounds are good you should have no distributor grounding problem).
I believe that a shorted coil could cause the modules to fail (uncommon but a possibility). More likely is a shorted coil capacitor(if equipped).
I would;
1. Verify the grounds and replace or add grounds where ever any questionable ground exists. I would also verify the presence of proper voltage and continuity at the module plugs (It might not be a module problem but an intermittent connection).
2. Check the distributor cap to verify that it has brass terminals, if not replace it with one that has brass terminals (replace the rotor too).
3. Replace the coil with an E type ford coil.
4. Strongly consider elimination of the Ford ignition box and install a MSD 6a triggered by the distributor (if you can make it work keep the ignition module as a back up and keep the plugs compatible so that the system can be switched back by just plugging it back in).

I would not mess around trying to replace the distributor with a different brand (the existing distributor is fine if it is electronic, although the pickups do rarely fail) or try any kludged together addition of a gm module.

Autozone stores have the same/no worse products than any other store. The quality of the store and the competence/helpfulness of its employees are a reflection of the manager (I tend to follow the managers when they switch stores locally). The replaceable parts on my 7 are about 3/4 autozone (lifetime warranty).
Hope it helps...
Enjoy!

'06 TJ Rubicon; seemed like a good idea at the time; had many CJs...
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post #9 of 33 Old 12-18-2007, 06:42 PM
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Quote:
Originally Posted by GPER
Is there any ground in the case of the Dura Spark?????
No, DuraSpark does NOT ground through the case.
------------------

Quote:
Originally Posted by biker250
Does this suggest that the ignition module is not "BAD" but rather just lost it's ground???
Not at all.
If the module looses ground during operation, or more importantly, is starved for ground, or the ground is intermittent, the module is usually toast.
I don't use the term lightly, if it smells like burned toast, it's almost always dead...

Starving isn't like a clean disconnect where the circuits are powered down all at once, with a bad ground, they are starved and heat up... Resistance builds heat, heat builds more resistance, heat builds even more resistance... POOF!
The magic smoke gets away!

Quote:
How confident are you that this is the problem and not something else that would require me to go with the GM HEI ignition module? I would prefer to not get into doing all that swapping of parts right now...I would like to keep the ignition stock until I decide for sure what I want to do with the motor. Thanks.
Virtually 100% sure with about a 99% margin for error!
Seriously, very few modules survive a ground failure. Sorry.
The good news is...
By using the plugs & case from your current module, your 'test' module is a plug and play unit.
If you want to go back to DuraSpark later, you just unplug the 'Stealth HEI' unit and plug in the DuraSpark module.

The other good thing is, once you make this 'Stealth HEI' unit, it makes a GREAT test module and backup module since the HEI module it's self rarely fails...
It's not the cleanest switching module, and it's not the best dwell control on the market, and it doesn't have a 'Start Retard' circuit, but it is as Dependable as a ignition module can be...
--------------------------------------

Quote:
Originally Posted by Happy Joe
Bad grounds can cause a variety of problems.
Aluminum is the best conductor of electricity after silver and copper, however it is prone to surface oxidation (the oxidation is a poor conductor).
WOW! This is going to be a long one!

Gold, sliver, copper, steel, lead and a number of other metals do a much better job as conductors than aluminum.
If aluminum were a better conductor, then electrical codes would recommend aluminum wire sizes twice the size of copper for the same current.

Aluminum does OK with high frequency AC, but it's a slug when it comes to being a DC conductor.
Free electron count has a lot to do with it, but grain structure has a lot to do with it also, which cast aluminum doesn't have.
Both your timing cover and distributor housing are cast aluminum.

Oxidation is a BIGGIE when it comes to high voltage DC discharges, especially when they have an air gap!
Aluminum will bond with oxygen (O2) quite readily, but in the distributor cap where ionized ozone (O3) is present, it's a non conductive crust waiting to happen!

Quote:
Adding grounds is cheap insurance and is easy. Brass bolts are unnecessary (IMO), Use stainless when bolting to aluminum as it will resist the galvanic corrosion that will happen to dissimilar metals in the presence of water.
I have posted time and time again that dedicated ground wires are a must if you want an electrical system that works every time, all the time!

I don't bolt to anything aluminum if I can help it.
Ground wires to heads (engine block optional, only a couple of sensors connected to block grounds) and Ignition module WIRING HARNESS!
Copper to copper.

Internal 'Star' washers designed to keep your ground bolts tight, and to keep your grounds connected through the heating and cooling cycles are strongly urged!

I use brass bolts for my common grounding lugs, the don't react as much with the solid copper terminals I recommend as some kind of steel would.


Quote:
(verify the block grounds and clean the distributor hold down it should make good contact with the block and distributor, if it (and the distributor are) clean and the chassis/block/battery grounds are good you should have no distributor grounding problem).
Run a dedicated ground to the module harness 'Black' wire and the distributor can be made of wood!
Distributor doesn't have to be grounded if you run the dedicated ground wire to the correct place!

Quote:
I believe that a shorted coil could cause the modules to fail (uncommon but a possibility). More likely is a shorted coil capacitor(if equipped).
Coil capacitors have no moving parts, are not direct current path device, and rarely, if ever, fail.

'Shorted' coils are usually a product of lack of ground path for high voltage discharge. Cumulative effect, and it sometimes occurs, but most of the time the opposite happens, when the coil discharges internally, it OPENS the windings, not shorts them.

Besides, using a HEI module will negate that problem. It can switch the full coil load (about 3 to 5 amps) with out a resistor or resistance built into the coil.

Quote:
I would;
1. Verify the grounds and replace or add grounds where ever any questionable ground exists. I would also verify the presence of proper voltage and continuity at the module plugs (It might not be a module problem but an intermittent connection).
2. Check the distributor cap to verify that it has brass terminals, if not replace it with one that has brass terminals (replace the rotor too).
3. Replace the coil with an E type ford coil.
4. Strongly consider elimination of the Ford ignition box and install a MSD 6a triggered by the distributor (if you can make it work keep the ignition module as a back up and keep the plugs compatible so that the system can be switched back by just plugging it back in).
Preaching to the choir!
Dedicated grounds, premium cap, rotor, plug wires, and if you can afford it, MSD 6 Series or other true CD ignition module.

Quote:
I would not mess around trying to replace the distributor with a different brand (the existing distributor is fine if it is electronic, although the pickups do rarely fail) or try any kludged together addition of a gm module.
As factory distributors go, it's real hard to beat the Motorcraft distributor. Reliable, tunable from the factory, upgradeable...

Using the Larger cap and rotor is a big help to getting the spark energy where it's supposed to go.
Stock caps suck when you can use the larger cap.

Switching to an E-core style coil will do you fine.

The 'Stealth HEI' and 'Motorcraft/HEI Hybrid' ignitions are both stop gaps when you can't get a reliable DuraSpark replacement, which is getting harder every day since more of the distributors are using the same few substandard off shore manufacturers...

Quote:
Autozone stores have the same/no worse products than any other store. The quality of the store and the competence/helpfulness of its employees are a reflection of the manager (I tend to follow the managers when they switch stores locally). The replaceable parts on my 7 are about 3/4 autozone (lifetime warranty).
There are a few places that still consistently have a better quality of parts... NAPA around here, but I'm seeing more and more of the off shore crap from them too.

In my particular town, the discount store to be at is Advance Auto... Mostly because most of it's employees are former dealership mechanics.

Just stopped in the new O'rileys a couple of days ago, and the assistant manager couldn't identify common disc brake pads... Didn't have a clue what they were.

The local AutoZone has employees that won't look for anything. If the computer doesn't pop it up right away, they can't open a paper catalog, and usually don't have a clue what things are or where they go...

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post #10 of 33 Old 12-19-2007, 06:59 AM Thread Starter
biker250
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Quote:
If so you probably gave the ignition module a ground again.
One of the only weaknesses the Motorcraft ignition system has is it ground through the distributor.

BINGO!!! Loosened the tab that holds the distributor down and tried to clean the mating surface a little bit and put the dist. back down and kinda "ground" it onto the block (just applied pressure & moved it back & forth.....AFTER marking dist & block to keep correct timing) and whaa la, it worked!

Then we kept trying to tweak a few things on the motor like vacuum lines & timing & belt tension so we were shutting the engine off here & there and all of a sudden, it did the same thing again....it would fire but immediately die so I tried it a few more times & got the same thing. Took the dist off again and tried to "re-seat" it and whaa la, it worked again.

The computer I thought was "fried" instantly worked again after I got it a good ground. THANKS for that tip Jeephammer!

'79 CJ7 lifted 4" suspension, 3" body.....trying to remove enough rust so the body stays in one piece
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post #11 of 33 Old 12-19-2007, 11:04 AM
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Quote:
WOW! This is going to be a long one!

Gold, sliver, copper, steel, lead and a number of other metals do a much better job as conductors than aluminum.
JeepHammer; Please review the conductivity of metals in any basic physics or chemistry text; you will find them ranked as follows silver best, copper next, gold then aluminum all the rest of your other choices rank below aluminum in terms of conductivity. Copper is chosen for wiring due to its relatively low cost, aluminum was an approved material for AC wiring until it was found that embrittlement and resulting fracture caused a number of fires, it was disapproved for residential wiring some years ago.

I believe however that we are in substantial agreement (you probably misread my post
Quote:
Aluminum is the best conductor of electricity after silver and copper
I neglected gold as it is rarely found in jeeps other than a few contact surfaces in switches).
Enjoy!

'06 TJ Rubicon; seemed like a good idea at the time; had many CJs...
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post #12 of 33 Old 12-19-2007, 12:45 PM
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Quote:
Originally Posted by biker250
BINGO!!! Loosened the tab that holds the distributor down and tried to clean the mating surface a little bit and put the dist. back down and kinda "ground" it onto the block (just applied pressure & moved it back & forth.....AFTER marking dist & block to keep correct timing) and whaa la, it worked!

Then we kept trying to tweak a few things on the motor like vacuum lines & timing & belt tension so we were shutting the engine off here & there and all of a sudden, it did the same thing again....it would fire but immediately die so I tried it a few more times & got the same thing. Took the dist off again and tried to "re-seat" it and whaa la, it worked again.

The computer I thought was "fried" instantly worked again after I got it a good ground. THANKS for that tip Jeephammer!
Run that dedicated ground over to the module "Black" wire and you won't have these problems.

Also, DuraSpark has two ignition circuits built into it.

One is 'Starting' and is only powered up when you are cranking the engine with the starter.

If that circuit is working, the 'Run' circuit should work also.
When you say it 'Fired' or 'Started' but wouldn't stay running...
The 'Run' circuit may have a power feed problem, or have an intermittent problem besides the ground.
---------------------

Quote:
Originally Posted by Happy Joe
JeepHammer; Please review the conductivity of metals in any basic physics or chemistry text; you will find them ranked as follows silver best, copper next, gold then aluminum all the rest of your other choices rank below aluminum in terms of conductivity. Copper is chosen for wiring due to its relatively low cost, aluminum was an approved material for AC wiring until it was found that embrittlement and resulting fracture caused a number of fires, it was disapproved for residential wiring some years ago.
You can always tell AC guys!

Common DC conductors, in order...
Silver, Gold, Copper, Lead, Low Carbon Steel...
Aluminum is WAY down there past Tin, Zinc & Chromium.

The reason is easy, Valance Shell Electrons.
Got to have those free electrons that will displace easily to make a resistance reduced conductor for DC.

There is a reason they put steel wires in the core of large amp capacity 'Aluminum' wires!

Aluminum is a lousy conductor for DC since it's resistance per foot is lousy.
It's conductivity for VOLUME is lousy.

(It's conductivity for WEIGHT is it's only saving grace, that and price...
it's light and cheap, much cheaper than copper for volume or pound!)

Since electrons in an AC circuit travel in a 'Back & Forth' motion as polarity reverse several times a second, the resistance isn't a huge deal,
but for the same current in DC, which is a straight line flow, resistance is a BIG deal!

Explains why aluminum isn't used in aircraft where weight is an issue... Most aircraft systems are long runs of DC wiring, and the resistance in Aluminum kills transfer, although the weight saving would be considerable, they can't use it...

Aluminum was dropped from NEMA code as a 'Common Conductor' (wall outlets and such) because it expands and contracts about 70 Times as much as copper.
Combine that with the resistance problems, and resistance causes heat, and the expansion & Contraction loosens connections, causing heating of the terminals and fires.

It's simple expansion and contractions of aluminum in terminals that weren't designed to expand & contract with them.

The 'embrittlement' issue you brought up was for flexible cords.
Aluminum work hardens when you flex it, and those wires did brake rather quickly!
NEMA dropped aluminum as a 'Flexible Conductor'.

Aluminum is still allowed for 'Fixed' or 'Non-Flexing' applications with with approved connectors that expand and contract with the aluminum.

Another thing, "Conductor" aluminum, or "Electrical" aluminum is an alloy with a small amount of other metals to help it's conducing properties,
And it's 'Drawn' or 'Forged' to create grain in the wire.

We were talking about a cast aluminum timing cover, that have no such conductor alloys and don't have the benifit of being forged.
Ditto for the cast aluminum distributor housing that have no such benefits, (and they also have god-knows-what in the aluminum mix!).

Add to that, Oil varnish (an excellent insulator, still used on 'bell' wire to this day!) inside the timing cover hole, and on the distributor stem.
Gaskets keeping the timing cover from actually contacting the block, and then you are down to oil varnish covered gears, and some rusty cover bolts to make the contact with the block....

Lots of stuff stacking up against that primary ignition ground!
Just easier to run a dedicated ground wire to the ignition module 'Black' wire and be done with it!
AMC/Jeep didn't want to spend the extra 6 for wire and connectors for a dedicated ground, but you probably should...

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Last edited by JeepHammer; 12-19-2007 at 02:45 PM.
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post #13 of 33 Old 12-19-2007, 10:21 PM
Happy Joe
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2006 TJ Wrangler 
 
Join Date: Jun 2007
Location: Colorado, USA
Posts: 2,398
For some reason we don't seem to be matching up (I believe our differences are largely semantic, as I agree with most of what you are saying but don't see where you are getting your data).

Most wires are drawn then annealed.

Some IACS electrical conductivities;
Copper (annealed, soft) 100%
Aluminum 61%
typical aluminum alloys as cast 20-30% (approximate range, I only looked at a few, the more additives typically the lower the conductivity)
Steels 3-15% (good enough for vehicle grounds)
Lead (Pb) 7%
IACS is an old system (some what outdated but still used) that uses soft annealed copper conductivity as a standard (100% @ 200 deg. C) and rates other materials as a percentage of the copper conductivity.

As a practical matter I measured the resistance of an (old greasy) aluminum 258 distributor housing from the top mounting surface to the hold down flange at approximately 0.5 ohm (not a lot) and roughly the same over roughly the same distance as a piece of 1/4" steel plate that I had laying around (hard to get good contact on the plate). A 6" piece of 14 ga stranded wire measured about 0.1 ohm (same meter). So while, as expected, the DC resistance of the distributor housing was relatively large (smaller conductivity) it was not overwhelmingly significant from a practical stand point, being roughly the same as several feet of copper wire.

I agree that contamination is bad in terms of conductivity and establishing good electrical contact. The best contact path to stock distributors (if they have no ground wire) is, probably through the distributor hold down including the bolt the conductivity through multiple rotating/sliding surfaces in an oil bath should be considered unreliable at best, IMO). (again we agree). However, I submit that the (relatively high resistance) ground path through the distributor/timing cover mounting bolts bolts and cast iron block renders thie conductivity through the moving parts point largely moot.

I believe the primary purpose of steel in the core in some aluminum wires and cable is to add tensile strength (allowing the wires to be strung over longer distances (aluminum has poor tensile properties in this application).

We agree use copper for grounds ...
Enjoy!

'06 TJ Rubicon; seemed like a good idea at the time; had many CJs...

Last edited by Happy Joe; 12-19-2007 at 11:09 PM.
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post #14 of 33 Old 12-20-2007, 09:42 AM
4.7stroker
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1988 YJ Wrangler 
 
Join Date: Apr 2007
Location: Rio Rancho NM
Posts: 4,298
Quote:
Originally Posted by biker250
'79 stock 4.2L. I keep fryin the stock ignition module. (The computer box that mounts to the inner fender) It works for a day or two then nothing. It'll fire up and immediately die. Anybody have any idea why this keeps happening??? Thanks for any help?

OK enough of the electronics theory bickering I am also a tech but who cares.
Back to the problem at hand.
As noted there are 2 ignition power feeds.
One for starting a straight 12vdc and one for running 12vdc reduced through a resistor wire knocking the voltage down to around 6vdc. It sounds like this wire has burned out/failed in some way.
I replaced my resistor wire with a length of 16g copper wire and added a balast resistor in series to reduce the voltage in "run" this worked out perfectly, I mounted the coil on the fire wall with the balast resistor and all works perfectly.

I hope this helps solve the mystery of why it will start but die when the ignition sw is put to "run"

Dwayne


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post #15 of 33 Old 12-20-2007, 05:17 PM
Fjguercio
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1978 CJ7 
 
Join Date: Dec 2007
Location: Burnsville, MN
Posts: 2,812
Question on 1.35ohm wire, grounding, Weber 34DGEC running rich

I am working on a 79 CJ7 with 258 restore. Thanks for your knowledge I did not know the distributor was the start of the grounding for the electrical spark system.

I installed a gasket on top of the block hole where the dist mounts and painted the fork that holds the dist down. I must be grounding by the shaft of the dist and block. After reading your info I may remove the paint from the bottom of the fork fingers to get/keep a better ground. I have a remanufactured engine so the shaft hole is clean.

I also have some questions that go along with your conversation. I will also post the below as another question. I am new to your forum and have been away from jeeps for 30yrs. It is good to be back.

First Question
I have read before about this 1.35ohm wire in my chilton book and may have removed it by mistake. I replaced all the slit tubing on my harnes and repaired where needed. There was a wire about 2 ft long with flat metal, non insulated, crimps on both ends just before the coil. It also looked like there was a wire spliced in there for the tac the prior owner had. I removed all the splices. I made a direct connection with the (red?) wire to the coil and spliced in a wire for the tac at the coil also. Is this the location of the 1.35ohm splice and what happens to the engine operation if it is removed.

Second Question
I am running rich. I have remanufactured 258, 1979 electronics with no feed back sensors such as O2, the EGR has been removed, borla header, Using 1981 aluminum intake 2 barrel, w/ water jacket heating and Weber 34DGEC carb. The cast iron intake/exhaust that are joined for heating are removed and the air intake heating from the cover over the exhaust has also been removed. The spark plugs are black and have some smoke & stinky order coming from the exhaust. Engine seems to load up at 2000rpm. The engine has 250 miles on it and not pushed yet.

RUNNING RICH AND EXHAUST HAS SMELL LIKE THE PAINT CURING AND LOOKS RICH. PLUGS LOOK RICH ALSO. I told Weber asked to hook up the Electric Manifold Heater but they did not know how to control it. I did so using the Jeep Heater manifold switch J3242321 that is NC and opens at 160F degrees and controls ground from the aluminum intake to the relay. The 12V key switched to the weber carb choke also starts the relay. When the engine is hot the Temp Switch shuts off the relay ground via interuption. This is similar operation as a 1983 CJ per the Chilton Book. The ground from the temp switch is the control and fused positive line go to a 20-40amp relay NO, normaly open. The relay mates and breaks the 12V positve to the heater. Yesterday took nice 40 mile trip or so and stil running rich. Weber also sent me two smaller jet,no directions??, but I have not installed them yet. I changed the Intake, header and carb but the rest is mostly stock. Starts nice, idel well at 650 675, and has ok power considering 33 tires. All new plug wires, dist rotar & cap, the distributor holds vaccum and is not binding, and the electric module tested ok at Advance Auto. Electric Choke open up to near verticle when hot.
?? Did I remve the 1.35ohm wire and can that make my engine rich?
?? Does anyone have experience with the 34DGEC on mostly stock 258 with header?
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