No Start Help 1982 FJ45

[bdsmitty88]

Hey. Sorry for the lack of updates. It had been a long time since I had been able to work on the truck. UPDATE: problem still not resolved, but narrowing things down a bit.

I haven't done any more advanced timing checks. I had ordered a carburetor rebuild kit and decided to tackle that first. I'll state a few things and then what my current symptoms are, then elaborate on how I got here. Hopefully this is easy to follow. Since my last update I have:

1. Rebuilt my stock Aisan carburetor, checked specs per the FSM. Everything seemed in order, except the bonded gaskets on the 2 insulator plates were a bit rough. The one between the two carb halves was really rough looking. I decided to simply oil them to let them swell, then bolted the carb back on.
2. With the rebuilt carb on, it took a while to get it started...more or less the same behavior as before. After 10-15 minutes of starting / stalling I was able to get it to start relatively consistently, but still took hammering the gas pedal a few times and was by no means immediate. Also, I typically had to hold the gas at half throttle and have the choke half out. The truck wanted to stall when I came off the gas pedal, after a few seconds. I could keep it running, for the most part and not well, by keeping on the throttle.
3. After about 30 minutes of messing around with things and the truck warmed up, my friend and I got it to start and idle around 650 RPMs but it would eventually stall. The carb did respond to idle adjustment screw changes. We could get it up to like 1600 RPM or so. We set the idle RPMs as best we could following the FSM. Overall, I'd say the problems were about the same as before, maybe slightly improved as I was able to drive it forward and backward a bit before it eventually stalled. Even at an idle of 650, the truck still sounded louder than normal.
4. Before rebuild, I had noticed that fuel leaked from the rotating throttle pin (the one that is just like a tolerance fit and rotates with throttle actuation). It has a bit of play to it, but I know this is common on old carbs. However, it mostly only leaks when cranking and goes away once the truck is running.
5. I noticed, now, that fuel was leaking from the middle insulator gasket, even while running. So, I decided to replace these.
6. I removed the old paper gaskets from both the middle and base insulator plates and replaced them, bonding them to the insulators with tacky gasket adhesive. I reinstalled the carburetor and there don't appear to be any fuel leaks from the middle insulator anymore.
7. I also ordered a new, Chinese carburetor off amazon to use as a comparison point. It was only $80 and, it's 100% identical to my Aisan 61012. I checked the specs of it (the ones I could without disassembling), per the FSM, while I was re-checking my OEM after fixing the gaskets. They were both dead on.
8. At the same time, I also ordered new distributor points and condenser, as I had replaced all the other easy things related to the ignition: key switch, coil, all plug / ignition coil wires, spark plugs, dist cap, rotor. I swapped in the condenser and the new points, setting the points by adjusting the rubbing block gap to .0118", per the FSM, using feeler gauges.
9. I reinstalled the OEM carb with the fresh insulator gaskets, now also with the fresh distributor contact points from step 8. The truck wouldn't start at first. I kept cranking to fill the bowl and pumping the gas pedal to squirt fuel into the carb. I eventually got it to start, but it was super rough, wouldn't hold idle, backfired a few times, and was super unresponsive. The idle screw settings remained unchanged from last time when my friend and I got it to idle as best we could.
10. Now, I have a new problem. Once I got it started, as soon as I pressed the throttle (like an immediate audible change), the truck would start to stall. The truck would idle, but not super smoothly, for a bit and then eventually stall. However, the second I put even a toe of pressure to the throttle, it stalled.
11. I examined the intake to the OEM carb and as far as I can tell it is getting great fuel spray from the accelerator pump (consistent, well atomized, etc.)
12. I then swapped on the new, Chinese carb to see if there were any changes to performance. The truck fired up quicker with the chinese carb, but it was also warmed up. It also idled quieter than when I just had the OEM carb on it (I didn't have my RPM gauge at the time to check exact idle speed). For the most part, with maybe a pump or two of the pedal, the truck would fire right up and idle well. Idle wasn't perfect, however. When it was smooth, truck sounded good as new, but it would blip occasionally and after a while might even stall. My friend and I dialed in the carb idle speed as best we could using the FSM method.
13. Interestingly, the truck displayed the exact same throttle behavior with the Chinese carb. The SECOND I applied any pressure to the gas pedal, the truck stalled. Again, fuel spray seemed great into the carb. All linkages were corrected appropriately.
14. The truck, with both carbs, started better without choke, would rev higher once choke was pulled, but would eventually stall.
15. My hypothesis started to shift back to spark / ignition. When the truck was idling with the Chinese carb, exhaust was clean and didn't smell strongly of fuel, so I don't think the truck was running rich at idle. I thought, however, what if the truck isn't getting adequate spark and blipping the throttle causes unburned fuel to stall the engine.
16. I can't, however, explain why before I repaired the insulator seals on the OEM rebuilt carb and before I replaced the dizzy points, the truck would respond well to the throttle being pressed.
17. I was able to check one thing which, again, pointed me back to ignition or spark. The very first thing I replaced, back when the problems first arose, was the ignition coil. I replaced the external resistor model for a newer internal one (brand new). At that time, two things were certain - the ignition coil (external, ballast resistor style) was overheating and evaporating the oil out from it and the carburetor choke butterfly valve had apparently been stuck closed since I took ownership of the truck (I noticed this before I removed it prior to rebuild). I decided to swap back in the old ignition coil / resistor with the Chinese carb setup since idle seemed better. I could not get the truck to fire with the old coil back in place, now with new points, condenser and carb. I swapped back in my new replacement coil and the truck fired up immediately...like instantly. Idle, again, was relatively smooth but still stalling with any press of the throttle.
18. The last thing I checked tonight was trying to pull plug wires while the engine was running to see if the engine would stall or there was a noticeable change in performance. No matter which cylinder plug wire was pulled, there was very little change to the performance of the engine. Maybe after 10-20 seconds of it being disconnected, it would edge closer to stall. I tried pulling two plug wires, simultaneously, and the engine ran slightly rougher and at a higher frequency. It still didn't stall immediately, however.

This is where I'm at now. Everything fuel related seems fine. Fuel bowl on both carbs fills halfway, super quickly, during idle. Fuel spray with accelerator pump seems adequate on both carbs. Engine behavior is, more or less, the same with both carbs. The distributor points, cap, rotor, condenser, ignition coil, spark plugs and all related cables have been replaced and checked per FSM where possible. I applied vacuum to the vacuum advance tube connected to the dizzy and it actuated the assembly as I would expect. I used an inline spark glow tester to observe spark. I have never used one of those and don't know how reliable they are. On any given cylinder, if you observe it during idle, it glows but not 100% consistently. I don't have a voltmeter capable of checking exact spark voltage or dwell / pulse coming from the dizzy. I haven't checked timing with any sort of accurate tools or measurement devices, but eyeballing it with the BB / indicator on the flywheel, it does seem close to where it should be.

The truck not starting when I swapped the older, seemingly less efficient coil back in along with it dying as soon as I blipped the throttle or a few seconds after applying choke made me think that the truck wasn't getting enough spark power from somewhere in the ignition circuit to burn the immediate richer mixture caused by fuel from the accelerator pump. What do you think? Could a vacuum leak somewhere, somehow be causing these issues? This might be totally unrelated, but just want to confirm since I'm unfamiliar. Older FJs, I believe, had a vacuum assisted transfer case. My 1982 SA FJ45 has the period correct split transfer, 4 speed case. Is there still anything vacuum related here? Right before I started having these problems, I had to drain my transfer case and replace the studs on the parking brake output flange that connects to the driveshaft. I replaced the appropriate shaft seals when I did this, refilled the T-Case. I don't see any leaks from it, and the brief period that the engine was running after the repair, the T-Case was working with no issues. I did replace the speedo cable o-ring, as it was recommended while I was down there, and something I did caused the speedo not to work. Not sure how I screwed that up. Again, probably unrelated, but worth mentioning everything.

TIA. I'm quite confused at the moment.

EDIT TO ADD: I previously checked compression as well. All cylinders were within the FSM spec. Some were close to the edge of the tolerance, but all within spec.

 

[firefighterjed]

Okay. You’re throwing the kitchen sink at this thing and not really getting anywhere. I’ll admit to not reading every single post in this thread but I do know that it’s time to get methodical about solving this problem. Make a plan, and rule out problems in order, without jumping around.

As was said before, there’s only spark, fuel and compression to deal with.

You checked compression and it’s good.

The fact that it kinda runs, and does better once it’s warmed up tells me that some spark is present and close enough to time to run. Let’s do two things for spark.
1. Check the firing order. Make sure that the plug wires go to the correct cylinder in the correct order.
2. I think you should get a timing gun and follow the FSM instructions to confirm that you’re close on your distributor position. Be sure to remove and plug the vacuum advance hose when you do it.

That gets us pretty stable on the spark side of things.

Now fuel. I think this is where your problem lies. I think it’s vacuum leaks but don’t jump straight to that.

Fuel system two zones: delivery to the carb, and delivery from the carb to the Cylenders. The first has components of Tank/lines/filter/pump/carb. If you’re seeing a fuel level in the middle of the sight glass on the carb when it’s running then you’re probably good in the tank to carb circuit. If not, any of them can be the problem but the simple obvious thing to rule out is the fuel filter. If it’s is new and securely clamped to its hoses, trace all the hoses. Make sure no kinks, no loose hose/pipe connections. If you have the wrong size hose it can introduce air into the fuel supply.
Test the pump. If stock it’s a diaphragm pump that is driven off the cam. You can check it by pulling the discharge hose, running it into a jar to catch the fuel and then try to start the rig. You should have vigorous spurts a fuel into the jar. When a pump fails is either leaks fuel out of the weep hole, or into the engine oil. Either one is pretty obvious when it happens, so I’m not suspicious of the pump.
Again, only do the above checks if you’re not keeping fuel visible in the sight glass when it’s running.

Now, fuel from the carb to cylinders is where I think you’ve got a problem. It helps if you understand that the cylinders moving down on their intake stroke with the intake valve open creates pressure deficit relative to atmospheric pressure (vacuum). That vacuum is present in the intake manifold and all the hoses connected to it the only actual opening in the intake should be the throat of the carburetor. That vacuum pulls air through the carb which entrains fuel into the air by venturi and the fuel air mix goes into the cylender. If there are any leaks or openings in the intake/vacuum system, air sneaks in and less air comes through the carb which creates an incorrect and very inconsistent fuel air mixture.

So, what can you troubleshoot?
Make sure that there are no intake leaks. All the hoses coming off the intake need to have hose clamps there and at their destination. There can be no uncapped openings on the intake.

There can be leaks at the base of the carb and where the intake manifold bolts to the head. Remember these leaks are sucking air in, so you can’t feel them. You have to spray carb cleaner or something on those connections while it’s running and if the engine revs or falters then the spray is getting sucked into the intake at that spot. Address those leaks.
If your 4x4 is vacuum activated I would disconnect those hoses from the manifold and cap the manifold bung. I don’t know how to ensure that the 4x4 shifter isn’t leaking so let’s eliminate it for now.
Valves have to be opening enough and fully closing to create vacuum. So a valve adjustment should be done when tuning up your rig. You’ll need a set of feeler gauges to set the valves. It’s not hard. Just follow the FSM.

Now set your carb up, again using the FSM.

So, here’s my list if I were you.
1. Verify firing order is correct
2. Verify timing with timing light.
3. Verify fuel always in carb sight glass when running
4. Check every hose that is hooked to the intake and the carb stack to make sure it’s secure and securely connected at its destination/ or removed and plugged where you removed it.
5. While running spray all around your intake and carb base with carb cleaner. Spray under the intake too. Sometimes they crack there. (Don’t spray into the throat of your carb. That SHOULD change rpm’s). Any change in engine speed indicates a leak. Fix it. Spray again.

Good luck!

 

[firefighterjed]

Also, that’s a really cool truck. It will be awesome to have it running reliably. I daily drive mine and it gives me great joy.

 

[jembourbe]

 

[bdsmitty88]

Just a quick little update...

@firefighterjed thanks for the detailed reply. I've noted all of that. Some of it is on my list, some of it I've already checked.

I had a solid gameplan going into today, but it all got thrown off a good bit. For whatever reason, the truck just ran so much worse today. Nothing has changed since yesterday. It was much more difficult to start and even after I got it warmed up as best I could, it just did not want to idle well and would eventually stall. I think most it ran at idle was for about 2 minutes. Same throttle / choke behavior as yesterday, however. Throttle blip or choking instantly stalled the engine.

I had previously confirmed relative alignment by sighting the flywheel BB to the approximate dizzy position. Now, as others have mentioned that doesn't mean it couldn't have been aligned to the exhaust stroke, but not sure how I would have had a truck that ran fine for 3-4 months in that scenario as the dizzy is clamped on nice and tight. I purchased a timing light gun this morning and my plan was to check timing and try to dial that in while I wait on my vacuum gauge to arrive tomorrow (wednesday) so I can check vacuum.

I couldn't get the vehicle to idle above 400 RPM and even then, it was constantly bouncing around between 250 - 350 most of the time. The idle mixture screw on the carb just wasn't doing much of anything to change idle. It was basically non responsive, til you adjusted the screw far enough that it would drop a bit and stall. I got it idling as best I could and tried to check timing, especially since I've never used a timing gun before and wanted to make sure I had the process down.

Hooked up properly, and connected to plug wire 1, the timing light flash was horribly erratic....like a few flashes, then a pause, then a few more, then a longer pause...no pattern to it. I had the plug wire clamp pointing in the direction that the instructions said, as well. I tried moving the clamp to each plug wire and results were the same. For whatever reason on plug wire 4, when I reversed the direction of the clamp, it flashed more consistently...this was only true for this wire.

I wanted to confirm the timing light was working, so I hooked it up to my 4runner and it worked perfectly...independent of the direction the clamp was placed on the wire as well. I moved back to the FJ to give it one more go and at least pointed it at the flywheel, but it was hard to draw any conclusions because the light pulses were so erratic. The BB was just moving all over the place, left and right. It sounds like all cylinders are just misfiring like crazy, and maybe the RPMs are so low and the misfires are common to each cylinder so the engine doesn't really sound like it's misfiring to the ear. It just has that "rough" running sound...that chugging along about to stall.

I assume attempting to check anything related to timing with this erratic of behavior and low idle is fruitless. I'm going to try and check vacuum tomorrow to see if there are any major indicators there. If for some reason vacuum readings are good, is it worth just loosening the dizzy clamp and rotating it a bit while the engine is running to see if I can smoothen it out and get the idle up?

Oh, and then this happened before I called it quits for the day. Admittedly I was frustrated in this moment and was trying to quickly swap the OEM carb in for the chinese one just to have another comparison point and see if idle was the same. I know the threads on my carb's fuel inlet fitting weren't great to start with as I could always feel them wanting to slip a bit. Anyway, my second wrench slipped off while I was tightening the fuel line fitting on and the threads went swiss cheese on me. What do you think is my best option here. I tried tightening things as best as it could but, as I figured, fuel leaked pretty bad. Should I try an epoxy? Self tapping thread fitting (not ideal as I would prob have to make a whole new fuel line), or try and heli-coil / timesert it back to proper thread size. I thiiiiiink there is enough sidewall there, but it will for sure be cutting things close. I have repaired engine threads with heli-coils before, but just want to see if anyone knows a better option here.

Thanks.

 

[firefighterjed]

That suuuuuuucks.
Just run the Chinese carb for now. It will run fine with it, just might not be “awesome”. Maybe jimC or mark can sell you a used top plate.

I’m less help with the ignition side. I have an HEI distributor from Davis (DUI). It has the coil built in and has been ZERO problem the entire time I’ve owned it. I’m a big fan. That also means that I don’t have much experience trouble shooting coil points condenser ingition systems.

The erratic timing flash makes me suspicious of your coil and points both. And also why did your other coil go up in smoke? Don’t want to wreck a second one.

I know there at affordable aftermarket version of all those ignition parts available in major auto parts houses. Maybe someone else can recommend a combination they use and have confidence in.

 

[bdsmitty88]

That suuuuuuucks.
Just run the Chinese carb for now. It will run fine with it, just might not be “awesome”. Maybe jimC or mark can sell you a used top plate.

I’m less help with the ignition side. I have an HEI distributor from Davis (DUI). It has the coil built in and has been ZERO problem the entire time I’ve owned it. I’m a big fan. That also means that I don’t have much experience trouble shooting coil points condenser ingition systems.

The erratic timing flash makes me suspicious of your coil and points both. And also why did your other coil go up in smoke? Don’t want to wreck a second one.

I know there at affordable aftermarket version of all those ignition parts available in major auto parts houses. Maybe someone else can recommend a combination they use and have confidence in.

I ordered some time serts and am going to attempt to tap and thread an insert in. I think I can get away with the 14mm diameter without compromising the wall. As long as their is ample wall clearance, it should be the best, most permanent solution.

I actually just replaced the points, cap rotor and condenser. The points are OEM toyota and the condenser, while not 100% identical in looks, was purchased off SOR and has the correct uf rating. The ignition coil is new, OEM, as well. The only difference is it is the internal resistor model, which shouldn't matter since Toyota officially discontinued the external, ballast resistor model for the internal ones.

While not 100% certain why the older ignition coil started burning off the internal oil, it isn't uncommon. Could be with age, as things wear and the resistance changes. I found a few threads of people noticing the same symptoms: steaming coil, and condensing oil splatter right above it on the hood underside. Nobody seemed too concerned about it...just said to replace. Who knows, it still might have been doing its job adequately, but I wasn't able to start the car yesterday when I swapped it in.

I'm hoping the vacuum checks tomorrow provide some obvious clues. I set the points gap per FSM spec. The only other thing I can do to verify that is to get a multimeter capable of reading dwell angle and crank the engine (I'll probably do this anyway).

I'm going to try some vacuum tests tomorrow and maybe realign the TDC markings by turning the crankshaft, then check the rotor positioning again for my own sanity. I might just go ahead and loosen the dizzy clamp and adjust the angle slightly while the engine is running to see if anything stands out. All I gotta do is mark its position beforehand and I can easily adjust it back to where it was.

Thanks!

 

[AussieHJCruza]

Surely if the timing gun is showing intermittent ignition, there must be something amiss related to ignition? From my experience, a vacuum leak shouldn't prevent it from running.

I'm not going to be a lot of help with troubleshooting as my truck has a very non-standard ignition setup, but something is wrong with the ignition. Also X2 on the DUI distributor, had good success on a previous 2F.

 

[firefighterjed]

You need to complete the “verify timing” step before you move on. Sounds like most of your ignition components are new. Is the correct voltage constantly present at the correct post of the coil? Maybe your if ignition switch or some old, bad wiring is causing your erratic spark. You can run a temp wire from battery (+) eliminating all that wiring and also remove, clean, and tighten grounds. Solve the spark mystery before you move on.

 

[Pirate323i]

Could you try some other high tension leads? (Borrow a set from a running motor)

 

[bdsmitty88]

You need to complete the “verify timing” step before you move on. Sounds like most of your ignition components are new. Is the correct voltage constantly present at the correct post of the coil? Maybe your if ignition switch or some old, bad wiring is causing your erratic spark. You can run a temp wire from battery (+) eliminating all that wiring and also remove, clean, and tighten grounds. Solve the spark mystery before you move on.

Yeah correct voltage is being delivered to the + terminal of the coil, before and after ignition. As far as I know there is no spec for what the voltage reading across the ignition coil (while running, obviously), since it's kind of all over the place as it's working. If anyone knows different...please chime in. I'll check resistances across the coil, today, just to be sure. I'll also check for spark against a ground from the dizzy side of the ignition coil wire when cranking. Aside from these tests, I can't think of any other way to test the ignition coil unless you had a super high voltage capable meter.

I assume by "verify timing" you mean eyeing the BB positioning compared to rotor positioning toward plug wire 1 connection on the dizzy? Ignoring the timing light for now, since that was an issue, is there a more accurate way of verifying the TDC positioning relative to Cyl 1 and rotor/dizzy? I think maybe I saw some forum posts where someone recommended putting their finger over the plug hole and feeling for vacuum draw?

I checked the relative BB/rotor positioning a few weeks back, so I can't imagine it has changed, but I will line it up again for my sanity today. Also, idk why I've seen so many threads with people saying "are you sure it isn't 180 degrees off, suggesting something with exhaust versus compression stroke" I'm not even sure what that means. The only thing that determines whether the cylinder is on exhaust or ignition stroke is whether the distributor fires the plug, i.e. 2 crank rotations per 1 rotor rotation.

I replaced the ignition switch as well, as the contacts on the old one were corroded a bit. No change noticed at all after replacing that. Battery is brand new, as well. I'll try running a wire directly from the positive post of the battery to the ignition coil. Is there any danger there? Is there a point to even trying this if the + terminal of the coil has good, consistent voltage pre and post ignition?

Do you know if the FSM specifies all the main ground locations? I couldn't find it anywhere. I replaced the battery terminals a while back and cleaned the ground connection from battery to engine block. Not sure where the other common grounds are off the top of my head. I also checked the ground from the coil to the dizzy.

Thanks, dude.

 

[bdsmitty88]

Could you try some other high tension leads? (Borrow a set from a running motor)

All leads are brand new. I tried the old ones as well just to confirm. No change, either way.

 

[bdsmitty88]

Surely if the timing gun is showing intermittent ignition, there must be something amiss related to ignition? From my experience, a vacuum leak shouldn't prevent it from running.

I'm not going to be a lot of help with troubleshooting as my truck has a very non-standard ignition setup, but something is wrong with the ignition. Also X2 on the DUI distributor, had good success on a previous 2F.

I don't have enough experience to say either way definitively, but I've had several other people say the behavior could be caused by vac leaks. Perhaps it's possible that the leaks are creating an improper mixture that isn't burning properly or igniting at all, even in the face of clean and consistent spark?

 

[45Dougal]

I don't have enough experience to say either way definitively, but I've had several other people say the behavior could be caused by vac leaks. Perhaps it's possible that the leaks are creating an improper mixture that isn't burning properly or igniting at all, even in the face of clean and consistent spark?

You mentioned that you set the points rubbing block gap to 0.0118".
I'm curious - I've never seen a points gap specified by setting the rubbing block gap before. Is this really what the manual says?
0.3mm sounds reasonable (we used to use a cigarette packet thickness).
Is the bearing on your distributor shaft tight? Whatever play you have in that shaft, will be play on your points gap.
Wiggle it with your fingers and see if it moves sideways.

 

[firefighterjed]

“verify timing” is just the title of the item on the organized list for trouble shooting. Trying to help you not bounce around so much. Since the timing light delivered erratic flashes you can’t verify timing and you need to resolve the spark problem before you move in to carb or vacuum or anything else.

Play in your distributor shaft, or point set too close as mentioned above sound like things that need ruled out.

 

[bdsmitty88]

You mentioned that you set the points rubbing block gap to 0.0118".
I'm curious - I've never seen a points gap specified by setting the rubbing block gap before. Is this really what the manual says?
0.3mm sounds reasonable (we used to use a cigarette packet thickness).
Is the bearing on your distributor shaft tight? Whatever play you have in that shaft, will be play on your points gap.
Wiggle it with your fingers and see if it moves sideways.

I'll double check side to side play on the shaft bearing but I don't remember feeling anything excessive before.

Yeah the FSM specifies setting the rubbing block gap. I'm going to snag a multimeter capable of measuring dwell, too, as an extra verification for the points setting.

 

[bdsmitty88]

“verify timing” is just the title of the item on the organized list for trouble shooting. Trying to help you not bounce around so much. Since the timing light delivered erratic flashes you can’t verify timing and you need to resolve the spark problem before you move in to carb or vacuum or anything else.

Play in your distributor shaft, or point set too close as mentioned above sound like things that need ruled out.

I forgot to check shaft play in the dizzy before my day got rained out, but I did try setting the points to a gap of .016, instead of the .012 I had before. No real, noticeable change. I felt like it was harder to start, initially, then once it got going maybe it was idling higher. Still, however, behavior was the same...rough sounding idle, probably misfiring, dies or backfires with throttle blips, and doesn't like to be choked once running.

In all scenarios, I still need to hammer the gas pedal 5-10 times while cranking to have any hope of it starting...which just seems weird to me because the fuel smell of the exhaust and backfires would suggest it's running rich to me.

I tried to check my ignition coil, per the FSM, but that thing is pretty much worthless as it only specifies the older, ballast resistor style coils. Regardless, here is what I measured with my coil, compared to what FSM spec says...

PRIMARY COIL RESISTANCE (between + and - terminal of coil)
-FSM: 1.2-1.5 ohms
-my reading: 3.2 ohms

SECONDARY COIL RESISTANCE (between + and high tension terminal)
-FSM: 8.5-11.5 kohms
-my reading: 8.1kohms

For what its worth, I measured my old, ballast style coil and neither the coil nor the ballast measured within the spec. It was a bit closer, but still noticeably out.

I also checked the voltage one more time going to the coil. IDK if these sound right or not...perhaps someone can confirm:
With ignition off: from battery positive to coil ground, Voltage = 12.58V (same as battery reading)
With ignition on: from battery negative to coil positive, Voltage = 11.22V (not sure if this is low or not)
With engine on: from battery negative to coil positive, Voltage = 14.1V

I'm not really sure if I can draw conclusions from any of those tests. My vacuum gauge and dwell meter didn't arrive today, so I couldn't check those. I did try spraying a bit of carb cleaner around the intake manifold and carburetor base, but couldn't register any changes...the truck was just always on the verge of stalling anyway.

 

[bdsmitty88]

It just poured rain here for a few hours. I went out to try and start it again, as I was planning to wiggle a few vacuum hoses and could not get the thing to start.

While I was out there, I pulled the dizzy cap off and checked for shaft play. The shaft has nearly zero lateral play. It seems perfectly fine to me. I checked the mechanical advance / spring back as well and took a video of it:



I've seen all sorts of dizzy rotor ends, but does anyone know what the gritty, grey material is on the rotor tip, why it's there and why it only goes partway on front, top and bottom? It was this way when new. Also, if a distributor rotor was aligned to an exhaust stroke, the truck wouldn't start and certainly wouldn't have run fine for 4 months, right?

 

[bdsmitty88]

A few more things to note and questions I have:

Questions

1. Does anyone know why my truck might have had a ballast resistor hooked to and in line with the + leads of the original coil? My starter does not have the connections for ballast resistor bypass. I was under the impression that ballast resistors were only in place with vehicles that were equipped with bypass. Do you think my truck initially had the starter with bypass, then it was removed and they just removed any bypass wiring on the coil end? Or, did the PO just add in a ballast resistor to try to keep the thing from getting super hot?

This was my original coil that had the ballast resistor wired in series
Amazon product ASIN B000ED8GG8

This is the coil I replaced it with, removing the ballast resistor as well
Ignition Coil - Internal Resistor - FJ40, FJ45, FJ55, FJ60 1958-1987 - https://cruisercorps.com/products/ignition-coil-internal-resistor

2. I've discovered some differences between earlier and later FSM and think I found where the confusion comes from regarding setting non-usa dizzy points using a .012 rubbing block gap against the dizzy hex shaft or using a .018" gap between the two point contacts.
I had been going off of the 1980 service manual which shows this...

However, in searching for proper internal resistor ignition coil resistance specs, I came across this 2F manual, supposedly from 1991. It seems to be what most people are referencing, as I've seen some of the diagrams in this manual posted on the forum
NOTE: my distributor does not have the "octane selector" however. Otherwise, it is identical. Notice the call for .018" gap between the point contacts at open.

Adding further confusion, a few pages later in this same manual is the identical spec as the 1980 manual but not for a "distributor w/igniter". This might all just be a coincidence and the .018" point gap corresponds to the ".012" rubbing block gap. You can see that this dizzy is a bit different than mine as well.

In this manual, I also believe I came across the correct ohm specs for the internal resistor coils, which would suggest mine is in proper working order....assuming I don't actually need the ballast resistor for some reason.

Sorry for the quick post succession...just did a deep dive back to when my problems started to see if I could make any connections. Nothing new stood out, but just thought of these things and wanted to make sure they are correct before I move on.

 

[45Dougal]

The voltages sound about right to me, but the main point is whether you consistently have a strong spark?
I see someone suggested bypassing the ignition switch and connecting the coil+ directly to the battery+; presumably that didn't help, indicating that the positive feed is not the problem.
From the video there are two things that jump out - the condenser capacitor is very scrunched up in there, and doesn't look comfortable - is it connected correctly, or interfering with anything? I see this is sometimes relocated on the outside of the dizzy.
Secondly, I can just about see a blue terminal on the switched contact - is this a good solid connection to the coil?
Did I miss a picture of the new coil installation (presumably its well grounded)?
All of this is irrelevant if you have a good steady spark anyway.
If you've been driving around on full choke for a while then I'd expect the head to be a bit coked up. Hard to check without removing the head though.
When it runs (badly), are all pots running sporadically or are one or two pots running well and the rest are not firing at all? (carefully feel each exhaust manifold before it's been running too long).
And finally have you checked your valve clearances?

That fact that its been raining and now your problem got worse, indicates an ignition problem, but maybe just luck of the draw.

Regarding the carb threading issue - how about tapping it out to a larger size and fitting a short adapter so you don't need to rework your fuel line?