Getting rid of learn burn.

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68383GTS

68383GTS

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I have a 1984 slant 6 D150. I want to replace the lean burn system. I believe I just need to replace the carb and put a standard electronic distributior on it. The carb is shot anyway. So should I replace the carb from like a 1974 D150. And could anyone recommend a slant 6 electronic ignition kit. I found a kit on EBay but it said you could not use it to replace a lean burn system. Not sure why I couldn't use it if I was replacing the whole electronic ignition.

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The statement may be a disclaimer for emissions. Believe it or not it still Federal U.S. law that you can not disable or remove emissions systems----clear back to 68 Federally, and in CA, 66

Does your system have a dual distributor pickup? If so I believe you will have to do a minor amount of re-wiring--I BELIEVE there is a relay in there somewhere to switch the dual pickups back and forth.

Sorry I have no documentation on these.
 
Been so long since I did a lean burn conversion that I can't remember what it involves beyond the removal of the lean burn computer and installing the standard electronic ignition system. There is a minimum amount of wiring that is necessary to make it work, there has to be a youtube somewhere that can help you. I don't think it takes more than a couple of hours at the most, and I don't recall having to swap out the carbs, but I could be wrong.
 
68383GTS said:
I have a 1984 slant 6 D150. I want to replace the lean burn system. I believe I just need to replace the carb and put a standard electronic distributior on it. The carb is shot anyway. So should I replace the carb from like a 1974 D150. And could anyone recommend a slant 6 electronic ignition kit. I found a kit on EBay but it said you could not use it to replace a lean burn system. Not sure why I couldn't use it if I was replacing the whole electronic ignition.

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I just did this on my 82 D150 slant. I took out all the lean burn crap and two fistfills of wires. I put in a Super Six distributor with the HEI conversion. It has maybe a dozen wires in the engine bay now. A regular intake, air cleaner, and carb rounds it all out.
 
All any Chrysler factory type ignition needs is a switched 12V signal. That's it. I would find whatever switched 12V is feeding the Lean Burn system coming from the factory harness before it gets to the lean burn and use it. Wiring diagram and test light are your friends. If it was mine, I would use an early to mid 70s Carter BBS or BBD, the one or two barrel respectively, whichever it has.
 
Carb, dist, wiring and a ecu (or a stand alone dist) you should be good. Watch out for the kits they are made overseas "authorized Mopar"
 
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67Dart273 said:
The statement may be a disclaimer for emissions. Believe it or not it still Federal U.S. law that you can not disable or remove emissions systems----clear back to 68 Federally, and in CA, 66

Does your system have a dual distributor pickup? If so I believe you will have to do a minor amount of re-wiring--I BELIEVE there is a relay in there somewhere to switch the dual pickups back and forth.

Sorry I have no documentation on these.
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I have a NORS dist. for these IF anyone needs such. $20 plus ship,Last one I have.
 
Another one in Illinois.... looks like a twin to mine (except mine's a year newer) same colors and all, yours looks in a lil better shape though.
I de-lean burned mine, and went a lil farther and did away with the fusible links as well, I added in a small underhood fuse box and wired everything that used to have a fusible link thru that. I have a fresh /6 on the stand going into mine, will hopefully have a little more oomph than the current original engine..... I had my cam reground, head and block shaved, bored, oversize valves put in, ported, going to a Super 6, and a few other goodies.....
 
as far as the "legal-ness" of deleting lean burn, all the parts catalogs list it as a "with-or without" thing. Meaning that they built these trucks either way in a given year.
Meaning that if "some" were made that way from brand new then it's OK to switch between ignition systems to eliminate one (or the other)
I've seen people do the delete and put the new ignition box inside the Lean Burn housing......
 
He doesn't specify which distributor he has... You're assuming it's a lean burn version. It could be.
 
68383GTS said:
I have a 1984 slant 6 D150. I want to replace the lean burn system. I believe I just need to replace the carb and put a standard electronic distributior on it. The carb is shot anyway. So should I replace the carb from like a 1974 D150. And could anyone recommend a slant 6 electronic ignition kit. I found a kit on EBay but it said you could not use it to replace a lean burn system. Not sure why I couldn't use it if I was replacing the whole electronic ignition.

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Nice D150!
Swapping out the Lean Burn will be a plus, better drivability and mileage.
And you don’t need a bunch of high priced parts like that Davis ignition to do it.
1) remove the Lean Burn ecu, it’s either mounted to the air filter housing or up in the driver side front fender. Find the wire that sends power to the LB when the ignition is switched to start and run.
Use that wire to power the coil and trigger a relay that powers a GM 4 pin hei unit
2) does the existing carb have wires that go to the float bowl? If so you will need a non lean burn carb. If not your existing carb will be fine. Assuming it is is a good functioning carburetor.
3) the locked lean burn distributor will need to be replaced with a Mopar electronic distributor with a mechanical and vacuum advance. One that is pre lean burn. Some of those are better than others for the existing ignition curve, but any of them can be recurved, not hard to do. The existing locked lean burn distributor is useful to someone running EFI. I use one with my MS3 Pro.
3) lots of posts on wiring in a hei module here at FABO . Slantsix.org also has posts specific to a slant six conversion. I like to power mine through a relay, easy to do. Go ahead and buy a real Delhi / Delco hei module, some of the knock off ones just don’t last. The hei will need a good ground and a heat sink, all of that is covered in the posts.
4) upgrade the coil to one that is designed for an HEI.
Do a little research then
gather up: electronic Mopar distributor,
Carb if needed,coil, hel module and heat sink, a relay and the appropriate wires and connectors, then do install.
You will like it.
 
volaredon said:
He doesn't specify which distributor he has... You're assuming it's a lean burn version. It could be.
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Since that's what the thread was about, I assumed he wasn't talkin about an Accel dual point. lol
 
Best to swap out the LB before it fails. My 85 D150 smoked the lean burn and stranded me in Redding CA for three days. LB control units arent really available, and no shop could help me because of CA emissions laws.
In the end, the parts list was for a '74 D150
Distributor
Ignition control module
Ballast resistor
Carburetor
Wire harness w plugs for dist & ecm
 
If like my 1982 Aries 4 cyl, your distributor has a 3-wire Hall-effect pickup and no mechanical or vacuum advance, which was done in the "Spark Computer" or lean-burn box. You should be able to install a 1970's e-distrbutor. Its VR 2-wire pickup can trigger a GM 8-wire HEI module and coil for 1985-95 GM V-8 trucks. Many posts. TrailBeast here use to kitted parts.
 
Nope. No Hall effect. The /6 and v8s were a different setup than the k cars
 
geminimotors said:
Best to swap out the LB before it fails. My 85 D150 smoked the lean burn and stranded me in Redding CA for three days. LB control units arent really available, and no shop could help me because of CA emissions laws.
In the end, the parts list was for a '74 D150
Distributor
Ignition control module
Ballast resistor
Carburetor
Wire harness w plugs for dist & ecm
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reviving old thread:

I have an 83 down here in San Jose, taking off the Lean burn system but still need to get the emissions test done. Did yours pass the sniffer test after the new distributor and Ignition module?

I'm leaving the cat on but was wondering if that's all I needed to overcome.
 
70DartCustom said:
reviving old thread:

I have an 83 down here in San Jose, taking off the Lean burn system but still need to get the emissions test done. Did yours pass the sniffer test after the new distributor and Ignition module?

I'm leaving the cat on but was wondering if that's all I needed to overcome.
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I don't know if they still check under the hood, but regardless of the tailpipe test, if you physically remove, disable, or alter factory supplied equipment, that WILL fail the inspection.
 
Yes, CA does a visual inspection under the hood and smoke-test the intake for leaks in the evaporative system. That is all they do on newish vehicles (say 2000+), other than poll the engine controller for codes. I think older still get a dyno test with tailpipe probe, at special STAR stations. New cars don't require any emissions test for 8 years, another bone to rich people as if the $7500 fed tax credit plus $2500 CA tax credit (even higher in some States) isn't great for rich people buying status battery cars to brag about their 0 to 60 mph times. If CA really wanted to reduce emissions and traffic, they would provide free school buses, like in civilized States. Requirements vary by County. In mine, my 1985 M-B diesel doesn't require an emissions test, nor my 1960's Mopars.

Might be failed if you replace the Lean Burn system with an earlier distributor with centrifugal and vacuum advance (handled electronically in lean-burn I think). Worst-case, if failed you can appeal to a referee who would likely OK it since parts are no longer available and the Lean Burn system is know problematic.
 
Could do a very simple Points Distributor too, they sell brand new ones at Rock Auto.

I use a simple points ignition system on the engine run stand for test firing engines.

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Had points on my '69 318 Satellite, never had to mess with it the 2 years I owned it.

Ran Great

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Simple is good.

Get a carb on there and good to go.

☆☆☆☆☆
 
George Jets said:
Could do a very simple Points Distributor too, they sell brand new ones at Rock Auto.

I use a simple points ignition system on the engine run stand for test firing engines.

View attachment 1716050697

Had points on my '69 318 Satellite, never had to mess with it the 2 years I owned it.

Ran Great

View attachment 1716050702

Simple is good.

Get a carb on there and good to go.

☆☆☆☆☆
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Found a sale going on for an electronic one with advacne and a GM HEI module. Just need to get the wiring down and will try to get this truck back alive and running. It's a bit of a turn, not gonna lie, but would like to get it going.

83 D150 with manual brakes, manual steering, slant 6 and a 4 speed.

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70DartCustom said:
Found a sale going on for an electronic one with advacne and a GM HEI module. Just need to get the wiring down and will try to get this truck back alive and running. It's a bit of a turn, not gonna lie, but would like to get it going.

83 D150 with manual brakes, manual steering, slant 6 and a 4 speed.

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Its easy to get running with the hei module and a good factory electronic ignition.
I have a 85 D150 with a 440 auto, its simple to wire, just use a good heat soak for the module.
 
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