I always admire the detailed info in your posts. 120mm—study the schematic— not rocket science— part of owning these 40s is forever chasing gremlins.
1975 FJ55 No Start, No Spark, No Understand
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I always admire the detailed info in your posts. 120mm—study the schematic— not rocket science— part of owning these 40s is forever chasing gremlins.
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- #22
I went through the wires and connections tonight; cleaned up my grounds and cut out the extra burned fusible link.
I even took an HT lead from another vehicle and tried to start it with that.
According to the 2F FSM, I have a bad coil. Or at least a coil that is out of factory tolerance.
I even took an HT lead from another vehicle and tried to start it with that.
According to the 2F FSM, I have a bad coil. Or at least a coil that is out of factory tolerance.
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hiya, if it's the coil, you can pick up a cheap one from autozone and see if it work. Then buy a better one and keep the cheap one for a trail spare.
best, ty
best, ty
I went back to your original post and see the primary is out of tolerance and the secondary is within tolerance.
But, I also noticed:
Or, am I misunderstanding this?
“I did a resistance test and primary circuit is 2.4 and secondary is 10.71.”
But, I also noticed:
“I've been trying to wrap my brain around cause; and when I touch the HT wire from the coil to the engine block, I get no spark.
I have 11.25 V with the key on to the coil, as well as coming out of the HT.”
Aren’t those statements contradictory, Drew?I have 11.25 V with the key on to the coil, as well as coming out of the HT.”
Or, am I misunderstanding this?
rkymtnflyfisher
Trout Bum
Any luck on getting the pig started?
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- #26
I'm getting battery power only to the HT lead, but it isn't giving spark. No contradiction involved.
I just got a el cheapo coil to throw at the problem, which I will do this evening. My regular job (yes, I finally have a "real" job) keeps me too busy to do as much as I like on Zeke.
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- #27
Welp, el cheapo coil fixed exactly nothing.
In the process of messing with it, I idly tested the external resistor. First, I noticed it was passing absolutely zero voltage with the key "on."
So I tested the resistance. 15.58 Mega Ohms. Huh. Can these units fail towards providing too much resistance?
In the process of messing with it, I idly tested the external resistor. First, I noticed it was passing absolutely zero voltage with the key "on."
So I tested the resistance. 15.58 Mega Ohms. Huh. Can these units fail towards providing too much resistance?
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- #28
BTW, with the new coil, I no longer get battery power to the HT outlet with the ignition key in the "on" position.
I still don’t understand how you have power to the HT lead, but no spark when you touch the dissy end of the HT lead to the block, while cranking the engine.
Have you verified your wiring is correct, as I suggested before? Could be a loose connection.
I have no experience with a ballast resistor... maybe someone else can comment.
Did you verify continuity on the HT lead?
Have you replaced your wires, especially the HT lead, as you suggested earlier?
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- Thread starter
- #30
I'd guess there is a short between the primary and secondary circuits, causing them to not induce the 40-80,000 volts necessary to throw a spark.
Edited to add: Then why do the two circuits read two different resistances?
That's a good question, though.
My ignition switch just went out on my 40 where there is no power in the "run" position but power on the "start" position, which made it easy to diagnose because it would instantly start then die when I let off the key. This has me wondering if your ignition switch is bad in just the opposite way, where you have power in "run" giving you good test results, but no power on "start" which would keep it from getting spark when actually trying to start it. Just a thought, could be way off.
Good luck.
Good luck.
BeerM3
SILVER Star
^^x2. My ignition switch is finicky too. If I crank it all the way forward to start, to where it won't turn clockwise any further, there's not enough juice to the starter to turn it over properly. It just cuts out as if the battery is dead. If I turn it about 80-90% of the way it engages and starts up fine. I've just learned to live with it. I was reading through your problems wondering if it could be something further upstream and not the battery or coil at all, but dogfishlake beat me to it. Jump the starter solenoid?
I didn't see a note confirming that you've cleaned all of your grounds. I chased a similar electrical issues for a few days, and ultimately solved the non-starting problem by replacing all the battery leads and grounds. There's info on that, and some advice from experts on the forum, in this thread: fussing and fighting with electrical after fusible link replacement Might be helpful to you.
Rudi (@bj40green),
Does this mean the external resistor is trashed?
What can you suggest, for Drew?
Thanks!!
bj40green
Tssss, tssss
So I tested the resistance. 15.58 Mega Ohms. Huh. Can these units fail towards providing too much resistance?
That resistor is dead! You must have a really good tester if you can read that value. Most testers display OL (Open Loop) or nothing with values above 1 Mega ohm.
The external resistor reduces the voltage to the coil after starting (when the engine runs) and is not part of the cranking circuit but with a defective resistor the engine dies when you let the key go from start to run.
Rudi
That resistor is dead! You must have a really good tester if you can read that value. Most testers display OL (Open Loop) or nothing with values above 1 Mega ohm.
The external resistor reduces the voltage to the coil after starting (when the engine runs) and is not part of the cranking circuit but with a defective resistor the engine dies when you let the key go from start to run.
Rudi
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- #36
That is good to know.
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- #38
I'm convinced I dinked up the external resistor when I replaced the coil. It wasn't out of spec until this last reading.
I'm not going to mess with it until Saturday.
Would it be possible to convert the system to an internal resistor system? I don't see why you couldn't rewire it to one. Replacement units are a) Used, and no guarantee they aren't trash as well. b) Obscenely expensive.
I'm not going to mess with it until Saturday.
Would it be possible to convert the system to an internal resistor system? I don't see why you couldn't rewire it to one. Replacement units are a) Used, and no guarantee they aren't trash as well. b) Obscenely expensive.
rkymtnflyfisher
Trout Bum
Time to upgrade to a full electronic ignition!
New dizzy, dented side oil cover, and new ignitor and you be all set for years!
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- #40
Is there a preferred kit available?
