1984 4x4 pickup failing spark from either coil

[Blue720]

10 hours ago, SamL said:

Quite the coincidence. I'm in Mukilteo also. Braven Metals is on Machias Road just before Granite Falls. They're much cheaper than P-n-P and not many 'pickers' (those that take parts to sell.) Office is next to the wheel and tire store. There are two 83's; a yellow 2wd regular cab and a blue 4wd king cab flatbed. Cost a dollar to enter. Helps to make a list of tools to bring. Grab a wheel barrow at the entrance if needed.

 

The yellow has been there longer so more parts are missing but the engine is still there. I tried getting the ignition unit out of this one but didn't have the tools.  I wish I took a picture of it.

 

The blue is missing the typical interior pieces, gauge cluster, door panels, etc. The engine is mostly untouched except the battery cables. I tried to get the carb off but failed again. Want to go away from a manual choke to an electric one.

 

 

The fun row is 34. Furthest from the entrance. That's where they keep the classic older cars. If you want to make money as a picker, that's the row to scavenge.

I went on the Braven website, and tried their interface, but it said they don't have any early 80's Nissans. I found a hardbody 86 with a V6

Edit: Looked again and found the two 1983 Datsun rigs. Thanks

Edited May 5 by Blue720
Looked again

[Blue720]

Went out to Braven today and the flatbed kingcab was missing the entire distributor, and the yellow regular cab had a 5 terminal ignition module. Not sure where to source from now.

[SamL]

Damn, someone must have taken it after I left. On a previous trip I wanted to look to see what plugs were in it but the wires were on too tight. But since you didn't take the 5 pin one, what are you looking for? How many number of pins?

 

Hope you got a few items from there, trim pieces, screws, etc. to make the trip worthwhile.

 

There are several people who partout 720s on the facebook group Datsun/Nissan 720's of Oregon.

[Blue720]

3 hours ago, SamL said:

Damn, someone must have taken it after I left. On a previous trip I wanted to look to see what plugs were in it but the wires were on too tight. But since you didn't take the 5 pin one, what are you looking for? How many number of pins?

 

Hope you got a few items from there, trim pieces, screws, etc. to make the trip worthwhile.

 

There are several people who partout 720s on the facebook group Datsun/Nissan 720's of Oregon.

I've got the 3 pin module. I'm not sure what the other PINS are even for(I suspect Tachometer), but the 5 PIN module is physically larger and won't even fit into my distributor. I was in somewhat of a hurry and didn't grab anything else. Didn't really see anything I needed. My rig is pretty much stock and has all it's parts. Might have been able to pull the coolant reservoir as mine is cracked, but it's been held together by a piece of vinyl tape for years. I suspect any 3 pin module would be the right one, but I don't have any proof of that. Wish I knew how to bench test the module I pulled from my distributor, just to verify it's the problem. My rig has all the symptoms, but my coils don't fire and they're getting 12 volts. I grounded the distributor and cleaned up all the connections...get nothing.

 

I just found a 3 pin on ebay, I guess I'll gamble the $45

Edited May 6 by Blue720

[SamL]

Larger Above Images:

https://imgur.com/x8dclHXhttps://imgur.com/x8dclHX

https://imgur.com/EXYNLS7

https://imgur.com/Nfpzpm6

 

 

[Blue720]

10 hours ago, SamL said:

Larger Above Images:

https://imgur.com/x8dclHXhttps://imgur.com/x8dclHX

https://imgur.com/EXYNLS7

https://imgur.com/Nfpzpm6

 

 

I attempted to follow that routine while it was on the truck, and I wasn't getting the voltages I expect from I and E poles. The B pole showed 12volts. That's what initially made me think my module must be bad. However I asked in a previous post if I had to ground both coils because the routine above isn't clear about it. Now that I've got the module out of the truck and home in my garage, I was wondering how to bench test it to verify it being bad, and when I get this 'new' one from ebay it would be nice to verify it being good.  

[SamL]

Have you tried continuity tests?

Assuming the 'primary' is on the left in the distributor, do a continuity test on the red wire: from ignition coil to either "I" or "E" (Intake or Exhaust?)

The 'secondary' or white-blue (blue in the above) wire would be opposite.

 

You could also check the Black-white wire (opposite the red wire on 'primary' ignition coil) to fuse block.

[Blue720]

9 hours ago, SamL said:

Have you tried continuity tests?

Assuming the 'primary' is on the left in the distributor, do a continuity test on the red wire: from ignition coil to either "I" or "E" (Intake or Exhaust?)

The 'secondary' or white-blue (blue in the above) wire would be opposite.

 

You could also check the Black-white wire (opposite the red wire on 'primary' ignition coil) to fuse block.

I'll try that if this 'new' used one doesn't work. Supposed to show up today. Will report back. Currently the old one is off the vehicle

[Blue720]

got the 'new' one, installed it, and I get fire from both coils. Still won't start though, so I pulled some plugs/wires and sure enough, intermittent spark. Going to replace the cap/rotor and maybe the plugs if they aren't firing after the cap/rotor replacement. 

 

One thing I'm concerned about is the 'reflector' as its called above. I made a mark so I could reinstall it after I removed it, but there is no index or other alignment key, just the roll pin. How important is it that the reflector is put back 'exactly' as it was? I could be off a degree one way or the other?  Any thoughts greatly appreciated. 

 

Best place to source a cap n rotor? Plugs/Wires?

Edited May 14 by Blue720

[Blue720]

Any thoughts on proper install, alignment of the 'reflector' in the distributor? I had to remove it, and I think I put it back the way it was, but I'd like to verify I've got it right.

[datzenmike]

The Nissan tachometer is run off the + intake side coil . 

 

You must mean the rotor? has the 4 bumps on it. It can't be wrong, it's held to the distributor shaft with a roll pin. The magnet and stator are on top of the module and it's pinned in place with two mounting bolts. The stator has a clearance of 0.5mm with the spinning rotor.   

[Blue720]

1 hour ago, datzenmike said:

The Nissan tachometer is run off the + intake side coil . 

 

You must mean the rotor? has the 4 bumps on it. It can't be wrong, it's held to the distributor shaft with a roll pin. The magnet and stator are on top of the module and it's pinned in place with two mounting bolts. The stator has a clearance of 0.5mm with the spinning rotor.   

In this picture, they call it a 'reluctor' and its held in place by the roll pin. Can it be put back on incorrectly? I tried to align it the same way I took it off. Was hoping it didn't impact the spark

 

[Blue720]

Went out to check some more things. Brought a spark plug tester, and all 8 are working fine. Checked all the plug wires and they're all within spec (~10K, manuals said <30K). Got good fire going to the cap from both coils, but I get slow intermittent spark at the plugs...so when the new cap n rotor show up next week, hopefully I can back it out of the drive and get it out of the way. Quite the headache it's been. Not sure what would make the cap n rotor work so poorly because I replaced it probably less than 5K miles, but it sat all winter in the cold. Contacts don't look corroded, but something isn't happening in there.

[Rustbin]

I don't know much about these systems but have had a short in a distributor cap, it was just a tiny carbon track between the plug contact and the base. It caused a slight miss in the beginning, then tracks spidered off to other plug contacts making it misfire like crazy. It's the only thing I can think of.

[Blue720]

Damn thing still won't start. Had to drag it out of the way. Now I got spark at all 8 plugs, but it won't pop off. Poured some good gas in the carb, and still nothin. Cranks, but it hits a 'hard' spot and stops, drags, then it cranks, hits a 'hard' spot, drags...etc. Maybe the starter is weak, but not sure what's causing the 'hard' spot. Like a clunk, but then it cranks again. Was thinking maybe water in the gas, but pouring gas in the carb I thought would circumvent that. 

[NC85ST]

If you have spark, it’s possible that the timing is off. 

[Blue720]

1 hour ago, NC85ST said:

If you have spark, it’s possible that the timing is off. 

Hard to say how that might have happened. It's always run fine. Just sat in the snow all winter, and then wouldn't start this spring. I haven't moved the distributor, just changed out the distributor "IC ignition unit" module. Do wonder how important the "reluctor" being reinstalled 'exactly' as it came off. I could be off a degree or so because there are no alignment marks. I attempted to get it back exactly as it came off, but not sure how to tell. It seems that shouldn't matter, but maybe it does. If anyone knows how to verify, it would be greatly appreciated.

Edited Wednesday at 08:57 PM by Blue720

[Thomas Perkins]

Had my 85 2.4 since 94 and never had to fool with my timing.Got over 405,000 miles on it.Only about 130,000 miles on Jasper engine I had installed in 09.Still same  Distributor..Still have original oil pump too.I did replace the big o ring that seals the distributor cap.The one built on the original  distributor dry rotted and broke apart.It is not a part that Nissan sells.I bought a 10 pack of them.The igntion part has the hump in it and is high dollar.Still the original one.If you were here we could swap them out and see if mine will work in your's and your's in mine.

[Blue720]

2 hours ago, Thomas Perkins said:

Had my 85 2.4 since 94 and never had to fool with my timing.Got over 405,000 miles on it.Only about 130,000 miles on Jasper engine I had installed in 09.Still same  Distributor..Still have original oil pump too.I did replace the big o ring that seals the distributor cap.The one built on the original  distributor dry rotted and broke apart.It is not a part that Nissan sells.I bought a 10 pack of them.The igntion part has the hump in it and is high dollar.Still the original one.If you were here we could swap them out and see if mine will work in your's and your's in mine.

Just wish I knew how important that 'reluctor' part needs to be reinstalled. It's just round, with a roll pin to keep it in place. I did my best to put it back where it was, but without any actual oem markings I can't be sure. I just eyeballed it and 'tapped' it back on. Made a little scratch on the out side of the distributor so I could keep track of it, but it wasn't a precision effort. It cranks strong, so I don't think the starter is the issue. It used to start immediately without much cranking at all. Just fired off and ran for 40yrs

[SamL]

A clogged catalytic converter? A non-carburetor equipped car would have problems this but a car with a carburetor?

 

Vacuum lines?

 

Stuck choke? or starved for air?

 

Just throwing out non-electrical problems out there.

[datzenmike]

The rotor is held onto the distributor shaft very precisely by a roll pin, you can't miss align it. Even is slightly out of position, being slightly advanced or retarded, the distributor timing is adjustable anyway. 

 

A 'clogged catalytic converter' would affect carburetor and EFI engines equally and it would not affect starting.

 

Pull a plug wire from the intake side and put an old spark plug in the end and hold against the grounded head. Have someone try to start the engine. Is there spark????? Now try the exhaust side. Either you have spark and there is nothing wrong, or you don't have spark. So... which is it.???                              

[Blue720]

2 hours ago, datzenmike said:

The rotor is held onto the distributor shaft very precisely by a roll pin, you can't miss align it. Even is slightly out of position, being slightly advanced or retarded, the distributor timing is adjustable anyway. 

 

A 'clogged catalytic converter' would affect carburetor and EFI engines equally and it would not affect starting.

 

Pull a plug wire from the intake side and put an old spark plug in the end and hold against the grounded head. Have someone try to start the engine. Is there spark????? Now try the exhaust side. Either you have spark and there is nothing wrong, or you don't have spark. So... which is it.???                              

Initially, after a long cold winter it had no fire from either coil. After breaking the coil terminals (they just twisted off when I attempted to loosen the bolts), I replaced the coils but still got no fire, so I replaced the IC Ignition unit inside the distributor. In order to do that I had to remove the 'reluctor', and I attempted to put it back exactly as I found it. I now had fire at the coil but intermittent spark at the plugs. So I replaced the distributor cap and rotor. I now have good spark at all 8 plugs, but it will not start. From your post it sounds like I may have gotten the 'reluctor' a degree or two off and my timing may be off. I didn't know if the 'reluctor' mattered as it pertains to timing, so next time I'm out there, I'll check the timing and see if I can adjust it. Thank you.