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superc_1

Member
1976 terra, 345, rebuilt Holley carb, new fuel pump, new everything, has been running great, but now it has decided to not start :(. Motor cranks fine, I have spark at the cap. Got gas at the carb even tried pouring some down the carb, cleaned and checked the rotor, but all the motor does in turns crank but no start?

Motor has been running great, but the last time I took it on a ride it started missing right before I got home with it? I pulled it up to the shed to unload some stuff and it set there for a hour or so and started right back up when I put it in the garge. Next morning get in it to go do some work and it won't start just crank only? Any suggestin? Fouled plugs, would the neutral safty switch stop it from starting?
 
If the neutral safety switch was tripped it wouldn't even crank over, I believe. You'll have to wait for a real tech to get a real answer, but in the meantime I'd guess at an ignition problem. Do you have a gold box?
 
Matt, thank you for your reply. I've got a gold box and I replaced it with one lying around. I can see spark at the plugs, but looks weak. I replaced the cap and rotor cause they had a wear spot in the cap, but this didn't do anything. Like I said it's been running great so I don't think its jumped timing? It will only crank but never fire. :idea: would be great if anybody has the time. I've tried very methodically to access the problem but to no avail.
 
Again my fair warning: I'm no technician. But in the meantime...

Fuel, air, spark.

Air: seems we can rule this out since you tried pouring gas down the carb, meaning I presume that the air cleaner was off and you have air.

Fuel: unless the carb rebuild is bad or the new fuel pump isn't working right, seems like you have fuel supply.

That leaves spark, and based on what you've written it still sounds like ignition to me. Replacing a gb with "one lying around" might not be sufficient to rule out gb failure, but I've never had a gb vehicle so I can't help you diagnose that.

Alternatively, I wonder if you're getting current in "start" mode but not in "run" mode. I just killed my Ford-style starter relay with water which caused the opposite problem: no start current, but it would run fine when I hot wired it. New relay = on the road again. Yours could be as simple as a rotted wire or corroded connection.

With my limited knowledge, if I were in your shoes, I'd pull out my wiring diagram and just chase every wire in the ignition system, verifying no burnouts and checking & cleaning every connection. Bet you find at least a couple bad ones if the wiring harness is still original. Special attention to the bulkhead connectors. I don't know whether your ignition incorporates that notorious 1.8 ohm resistor wire that runs to the coil, but mine was one of many burnouts on that wire.
 
superc_1 said:
Matt, thank you for your reply. I've got a gold box and I replaced it with one lying around. I can see spark at the plugs, but looks weak. I replaced the cap and rotor cause they had a wear spot in the cap, but this didn't do anything. Like I said it's been running great so I don't think its jumped timing? It will only crank but never fire. :idea: would be great if anybody has the time. I've tried very methodically to access the problem but to no avail.
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These engines can't "jump time". No way...no how....unless a came gear shears or the nose of the camshaft itself breaks off which is a lubrication issue caused by failure of the #1 cam bearing.

Substitute a known good gold box amplifier. That is how we troubleshoot this stuff. This is a classic gold box failure mode.

Neither electronic distributor option used on the Scout II app (either prestolite idn or Holley gold box) uses a "resistor wire" in it's operation. That item is only used when running a breaker point distributor system.

edit: at cranking speed you should observe at least a 1/2" heavy spark when holding any spark plug terminal close to a good engine ground.
 
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Mm
I just read your motor build thread on sonja? The gold box that I put on is a known good gb. I'm going replace the coil but only after everything else has been verified. Do you need a resistor installed with a new coil? I made sure that the coil reads between 1.4 and 1.8 ohms
 
superc_1 said:
mm
I just read your motor build thread on sonja? The gold box that I put on is a known good gb. I'm going replace the coil but only after everything else has been verified. Do you need a resistor installed with a new coil? I made sure that the coil reads between 1.4 and 1.8 ohms
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Even if the amplifier you installed was "known good" that does not mean it's still functioning correctly! Those items can die an instant death in exactly the manner you describe....or they can die a slow death by going dead only when heat-soaked and then coming back to life after cooling down.

And...that type of failure is not only found regarding the Holley gold box (many of those "boxes" are also silver or black in color, each is for a specific application). The Ford electronic ignition amplifier that was introduced around 1975 and used well into the 90's was also afflicted with this problem...the oem boxes are shit and very expensive, the cheepass aftermarket chinee and messkikin replacement boxes are very durable.

Same holds true for the chrysler electronic ignition amplifiers intro'd in 1972.

And before simply swapping out a coil, why not test the existing coil using an ohmmeter at least?

Primary resistance on any IH-type coil (no matter which ignition system is present) should be between 1.4 and 1.8 ohms, no more than 2.0ohms. Secondary resistance should be in the range of 8k>12kohms.

Again, with the gold box or the prestolite electronic ignition systems, no external resistor or resistor wire should ever be incorporated in the switched power feed to the coil or ignition amplifier. Pay no attention to any kind of "warning" printed on any coil regarding a "resistor" or "no resistor", those warnings mean nothing in the ihc world, that is generic bullshit that should have never been printed on the coil in the first place if the proper part number coil is installed on any given vehicle/ignition system.
 
This might be a good time to step into the 21st century and pop for a pertronix/msd combo. As Mike said, those ghost boxes can fail all at once, or over time. I had them do both. And everything in between. When I was still running one, I carried no fewer than 3 spares (no b.s.). Back when there were still IH vehicles in my local wrecking yards, I would grab as many as I could find. But even when they do work, they still are no match for a multi-spark, modern ignition. I'd recommend points before a ghost box ignition. The off-idle response, and wot performance alone are worth it in my book. Yeah, its a chunk of cash you May not want to part with, but "bang for the buck", its probably the best performance upgrade you can make to one of these motors. The gold box is just heartbreak and misery in my opinion.
 
dealbreaker74 said:
this might be a good time to step into the 21st century and pop for a pertronix/msd combo. As Mike said, those ghost boxes can fail all at once, or over time. I had them do both. And everything in between. When I was still running one, I carried no fewer than 3 spares (no b.s.). Back when there were still IH vehicles in my local wrecking yards, I would grab as many as I could find. But even when they do work, they still are no match for a multi-spark, modern ignition. I'd recommend points before a ghost box ignition. The off-idle response, and wot performance alone are worth it in my book. Yeah, its a chunk of cash you May not want to part with, but "bang for the buck", its probably the best performance upgrade you can make to one of these motors. The gold box is just heartbreak and misery in my opinion.
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I would too!

The correct pertronix conversion is ho-181 for the gold box distributor only. And...a pertronix hall effect unit will trigger any capacitive discharge system in the "six" series (but not an msd "digital" six). It will trigger a mallory six digital box.

Or...a pertronix ho-181 will trigger the oem coil only for now and the cd box could be added later.
 
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My .02$, I had the same gold box issues. I spent months trying to get an ho-181 pertronix (this was several years ago) but they weren't in production yet. I went to napa and bought a point type distributor and put a pertronix unit and a pertronix epoxy coil in that. That also got me a spare vacuum advance. I've had no trouble with the ignition since. Other that the pertronix epoxy coil I had installed. I spent much time on the phone with Mike mayben from moab, utah trying to diagnose a wierd ignition problem. Only when I got back to sacramento did I figure out it was the coil. I replaced it with an oil filled coil and that solved it. I've read elsewhere here that the epoxy coils were problematic.
 
lou said:
my .02$, I had the same gold box issues. I spent months trying to get an ho-181 pertronix (this was several years ago) but they weren't in production yet. I went to napa and bought a point type distributor and put a pertronix unit and a pertronix epoxy coil in that. That also got me a spare vacuum advance. I've had no trouble with the ignition since. Other that the pertronix epoxy coil I had installed. I spent much time on the phone with Mike mayben from moab, utah trying to diagnose a wierd ignition problem. Only when I got back to sacramento did I figure out it was the coil. I replaced it with an oil filled coil and that solved it. I've read elsewhere here that the epoxy coils were problematic.
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Once again all I had to do was keep reading post's and I get more info :icon_up: just got my flamethrower 2 epoxy filled !!! Should I send I back for the oiled filled ?? This is the first I've heard about epoxy failure ........
 
My friend bought a traveler from a guy who could not keep it running.
After spending thousands at a shop, (they replaced the tq, tuned it, timed it, adjusted it,)
still ran like crap so he sold it to my buddy for $800.
I put a different coil wire on it and now it flies like a p-38.
 
Two more cents: I wouldn't toss a pertronix epoxy coil that works, but I would, and do, carry a spare coil in my truck. When I had my problem I called pertronix and they shipped me a new epoxy coil. I'd already installed a pertronix oil filled so the epoxy is now my spare. The comments I read on IH forums regarding the epoxy coils were anecdotal and wouldn't keep me from buying another.
 
Any ignition coil can fail at any time, no matter what the brand name, what the design/construction consists of, how "old" it is, etc. They are dam simple devices, the "oil-fill", "pitch-fill", "epoxy encapsulation", versions are all the same basic construction, a primary winding, a secondary winding, and a soft iron core.

Any ohmmeter can be used to make a simple, basic check of any inductive ignition coil,...make a primary winding resistance/continuity test and a secondary winding resistance/continuity test and compare the results to the published specifications for the part number being tested. And that is at ambient temperature. With the resources available on the 'net any coil spec can be found, you just have to do the work on either the manufacturers support site, in the marketing guapo for the product, or in the detailed description windows seen in the online parts lookups.

Then repeat the same tests once the system is up to full operating temperature and compare readings. The most common failure mode for a coil is that as it heats, it's internal winding(s) fail and operation becomes erratic, then it "repairs" itself after cool-down.
 
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