Help: duraspark conversion

[Jutter]

I have done the duraspark conversion to my 1984 2.8L BII. I followed the tech artical provided in the tech area. I installed every thing and attempted to start the truck up but nothing. It cranks but doesn't run, so I pulled a plug to see if I was getting spark. At first there was spark while cranking then I realized that my plug wires were out of order. I corrected this but still nothing. So pulled a plug again and noticed that now there is only spark when I let off the key from cranking. The original wiring was pretty bad and the p.o. had in stalled a resistor for tfi coil. So for now a couple questions:

#1) should I have installed the resistor for the duraspark coil? The new coil didn't come with one and I didn't see anything in the write up about it or maybe I have over looked it.

#2) So now that I'm only getting spark in the run position, does this mean my duraspark modual is fried? I tested for voltage at the connector in the truck and found that there is voltage coming in when cranking and in the run position.

Any thoughts / advise would be appricated.

 

[PetesPonies]

I did the Duraspark conversion on my '84 a few years ago. When I switched engines ( V8 ) i kept it. It has worked great. But I used a GM HEI module along with the Duraspark distributor. $19 and works better than the stock box IMO.

 

[Spede Demn]

Kind of sounds like you might just be missing a wire from the ignition switch to the coil, or possibly the wrong wire maybe. Not much help really but I did the duraspark conversion on my 85 B2 using the TRS tech article and never had a problem with it.

 

[Jutter]

I think I'm gunna try the hei module. Can I use the power wire from the duraspark connector to power the hei module?

 

[Spede Demn]

Did you buy all new electronics or get used stuff? I bought all new and did the conversion over xmas just 3 months ago.

I have my B2 inside the shop at work every evening, could go over it in more detail via txt message if you want?

Im old and forgetful but I think there was two wires needed to be spliced together to get power to the coil... is that what you have?

 

[kimcrwbr1]

Have you removed the complete computer wiring? the only wires you need to cut from the 8 wire connector by the coil are for the computer hopefull you cut them long for future use? I just connected the two wire connector the red and white are backwards but still correct. I used the computer power wire for the coil and just run athe green wire from the module to the coil neg. I found a distributor harness from a 84 4 cyl and was plug and play. basically the only two wires spliced are green to coil pneg and key on hot to coil pos. Do you have the distributor in the correct position. One trick to get it running is shine the timing light on the timing marks and just find the wire that gets close to TDC. Put hat wire on the #1 plug and set the firing order from there. If that dont work rotate the wires 180 degrees and try again 1-4-2-5-3-6

 

[kimcrwbr1]

I am using the stock TFI coil without resistor.

 

[Spede Demn]

I dont 'think' that coil will work.. but I didnt try it.

 

[PetesPonies]

I use the stock TFI coil with the GM HEI module and it is fine.

 

[kimcrwbr1]

Yea I was messing with the vacuum line for my auto tranny it is right next to the dizzy when the engine was running and I knocked a plug wire up on the cap it didnt shock my hand but I was leaning close to the fender. Put it this way I now know what it means to get it knocked in the dirt. The TFI coil really bites.

 

[PetesPonies]

You probably only got small amount too . . as a coil will discharge whenever it can. Conditions outside a cylinder are easier an arc to happen, so you probably didn't get it's full charge

 

[Spede Demn]

So Im confused... are you using the original square coil connected with the electronic ign module and with a vacumn distributer? and still have the computer hooked up? if so why?

I did everything exactly as the TRS tech article and threw away everything else, no computer, no polution control, nothing. I have a distributer, a coil w/resistor, and an ignition module.

 

[kimcrwbr1]

All the computer wires are gone at the grey 8 wire connector by the coil there are a couple hots use the key on hot for the coil. the other wires ar for the guage senders and alternator to regulator. You only need to cut a couple wires from that connector to compleetely remove the computer harness. I hope you cut them long?

 

[Jutter]

I picked up an hei module to try if I can't get the duraspark box to work.

I think the problem I'm having is that there is no power to the coil when cranking. I need to find a way to power the coil when cranking and in the run position. I have a brown with pink wire that is where the write up says to power the coil. So I put a test light on it when cranking and there is power there but no power when the key is returned to the run position.

Even if I do end up using the hei module how do I power it during cranking and in the run position?

 

[Spede Demn]

In the plug from the ignition switch you should be able to find a wire that is hot only when the ignition is in the 'cranking' position, and another one that is hot only when the ignition is in the 'on' position... splice them together and run to the + coil.

 

[Jutter]

Today I tried splicing a couple wires together to get power to the coil during "cranking" and in the "run" position. I wired every thing back up and turned it over, now I can get it to start but it won't idle. So I am now gettiing spark but my timing may still be off. Could the distributer be off a tooth on the gear? Does the fact that it will run mean that I'm close to the timing mark and can adjust by turning the distributer?
Also I'm using a 2100 carb. It has the 1.08 Venturi and the jets that are in the carb have the same markings in them as the original carb so I didn't change them. Should I swap these or is it possible that these are the same jets?
If I could get the truck to stay running I could dial the carb and the ignition in.

 

[Spede Demn]

If it starts at all then the distributer is at least close to where it needs to be, could still be off by a tooth tho. Set the timing mark on the front of the crankshaft to TDC and check where the dist rotor is pointing, make sure you still have room to turn the dist for timing.

Check all the vacumn lines and ports are either hooked up or at least plugged off, 'IF' you have left any of the polution control stuff on the truck it can be blocked off or removed, it useless now anyway and could be the reason it wont idle. Once you take off the air pump thats below the alternator you'll need a shorter alt belt, its now the same size as the power steering belt.

 

[Jutter]

I checked my timing, changed the jets in the carb to the jets from feed back carb and checked for vacume leeks. So I've got it running now. There's still a couple bugs to work out: when I turn off the ignition switch the engine keeps running and I need to tune the carb more.

 

[Spede Demn]

So first it wouldnt start.. now it wont stop.. lol

just guessing here but I would trace the 'ignition on' wire you spliced to the coil and make sure it isnt connected to the alternator somewhere allowing it to remain hot as long as the alt is turning.

 

[Jutter]

Well it's running!! Still have some minor bugs to work out but all in all it runs well.