Wits' end with no spark (really long post) '76 FJ40 (1 Viewer)

[Pin_Head]

The way to test it systematically is:
1. Check if the coil can make a spark. Disconnect the wires at the coil, run a wire from battery + to coil +, momentarily ground the - and check for spark. If you get a spark then:
2: Check if the ignition switch circuit works: Reconnect the wire from the ignition (ballast resistor), turn key on, momentarily ground the - side of coil and check for spark. If you have a spark, then check ignitor. If no spark, check wire connections and ballast resistor.
3: Check ignitor: reinstall wire from ignitor to the - side of the coil now everything should be connected back to stock condition. Turn the engine until points are open, turn on key and momentarily short between the points and check for spark. If you have a spark, then check point gap, clean points. If no spark, remove ignitor wire at - side of coil and connect - side of coil directly to the points wire coming from the distributor. Check for spark when turning over or see if it starts/runs.

 

[sggoat]

"what is this" is a ballast resistor for the ignitor itself.
The one you replaced is the ballast for the ignition coil.
Neither of them are known to fail.

A bad coil will have zero or infinite resistance.
Put the good Toyota coil back in place, there's nothing wrong with it and it did run the engine before. The untested Chicomm coil should be returned to Vatozone.

On the diagram, there should be a single wire connected to coil - from ignitor. IDK what "ballast bypass resistor" is.

agree with this----

 

[Red Panda Roll]

The way to test it systematically is:
1. Check if the coil can make a spark. Disconnect the wires at the coil, run a wire from battery + to coil +, momentarily ground the - and check for spark. If you get a spark then:
2: Check if the ignition switch circuit works: Reconnect the wire from the ignition (ballast resistor), turn key on, momentarily ground the - side of coil and check for spark. If you have a spark, then check ignitor. If no spark, check wire connections and ballast resistor.
3: Check ignitor: reinstall wire from ignitor to the - side of the coil now everything should be connected back to stock condition. Turn the engine until points are open, turn on key and momentarily short between the points and check for spark. If you have a spark, then check point gap, clean points. If no spark, remove ignitor wire at - side of coil and connect - side of coil directly to the points wire coming from the distributor. Check for spark when turning over or see if it starts/runs.

I will try this today and let you know what I come up with.

Okay. Step 1. I got bright blue spark from the coil-to-distributor HT line when grounding it to the head.

Step 2. The spark jumping from the HT line seems much weaker but was there.

Step 3. No spark when shorting between (open) points with a flat head screwdriver. I also tried a piece of 10 g wire.

After disconnecting ignitor (black) wire from coil (-) I tried arcing across the points again and got a nice bright blue spark. Then I cranked it with spark plug #5 grounded to the block and there is a bright spark there, too! I re-gapped the points and put it all back together. Fingers are crossed.

THANK YOU for your help!

Question: Should the coil (-) be directly attached to the (red) wire that goes from the ignitor to the distributor by itself or should the red wire still be plugged into its connector that goes to the ignitor. Right now they are both (the coil (-) and red wire) attached to the distributor through one wire.

It still won't start but now I know it's NOT because of a spark issue any more. I think the three weeks without running has made it sad. It's starting to sputter a little. I think I'll be able to get it going tomorrow. Here's hoping.

Can I drive it with the ignitor bypassed like this?

I came across a "how to build a GM ignitor" the other day but it was for models newer than mine (1978, or '79 I think). Is there a how to build an ignitor with locally available parts for vehicles with points ignition? (Mine is a 3/76.)

 

[Pin_Head]

Your igniter is bad. You have several options.
Replace it
Replace it with a Perttonix.
Repair it. Chances are it is the PNP power transistors or a corroded connection including the ground.
Replace it with a later distributor
/ ignitor.
Bypass the ignitor and run straight point but you will need to add an ignition condenser from the coil - to ground.

 

[Red Panda Roll]

I think I'll try the Pertronix route. This has been a pain and I'm hoping going electronic will simplify things. Thanks again, everybody, especially you @Pin_Head for your help in diagnosing this!

 

[Red Panda Roll]

@Pin_Head, I am so grateful for your assistance in troubleshooting this! I pulled my points, installed the Pertronix module and started the truck up immediately! It's running great now. I couldn't have done this without your help. If there is such a thing as Cruiser Karma, you've got some good stuff coming your way.

 

[CarDude]

@Pin_Head, I am so grateful for your assistance in troubleshooting this! I pulled my points, installed the Pertronix module and started the truck up immediately! It's running great now. I couldn't have done this without your help. If there is such a thing as Cruiser Karma, you've got some good stuff coming your way.

This is what I love about this site. People genuinely want to help and share there wisdom. This makes it possible for the not so mechanically inclined person to own and maintain there landcruisers with out having to spend a boatoad of money at the automotive shop.

 

[brooklyn]

@Pin_Head

I am not getting any spark from my coil and wanted to follow the bellow, but I am a bit confused on step 1. If I understand correctly, I connect a wire from the + battery to the plus side of the coil - got that. It's the momentarily ground the negative terminal & check for spark - need a bit more detail on this step. Am I grounding the terminal and looking for spark from the coil wire (engine not turning over). I am just not visualizing this step.

The way to test it systematically is:
1. Check if the coil can make a spark. Disconnect the wires at the coil, run a wire from battery + to coil +, momentarily ground the - and check for spark. If you get a spark then:
2: Check if the ignition switch circuit works: Reconnect the wire from the ignition (ballast resistor), turn key on, momentarily ground the - side of coil and check for spark. If you have a spark, then check ignitor. If no spark, check wire connections and ballast resistor.
3: Check ignitor: reinstall wire from ignitor to the - side of the coil now everything should be connected back to stock condition. Turn the engine until points are open, turn on key and momentarily short between the points and check for spark. If you have a spark, then check point gap, clean points. If no spark, remove ignitor wire at - side of coil and connect - side of coil directly to the points wire coming from the distributor. Check for spark when turning over or see if it starts/runs.

I did bench test the coil and it is in spec. Terminal to terminal was 1.7 ohms, and terminal to coil post was 9,000 ohms.

Swapped in a second ignitor & coil as well and still no spark. I have a 85 F2 in my "67 FJ40, so it's the wiring is pretty basic.

 

[Pin_Head]

That is correct. Connect the + battery to the + side of the coil. Pull the center wire from the distributor cap and position the end 1/8 inch away from the block. Momentarily ground the - side of the coil and you should get a fat juicy spark. Measuring the resistance of the coil tells you the same thing.

Step 3 is for the points style igniter from 75-78. If you have a 85 ignition and swapping the late style igniter did not solve the problem, then you may have a bad pickup coil inside the distributor.

 

[brooklyn]

Did the above and no spark. I am using a test light to ground the coil and, it lights up when I momentarily touch - is it supposed to?

 

[Pin_Head]

I don’t know if a test probe has a low enough resistance to saturate a coil. Just use a piece of wire. Put the end of the high voltage wire about 1/8 inch away from grounded metal.

 

[brooklyn]

Okay, re-did the coil test and no spark. I am getting 12 volts to the coil and using a wire to ground the neg on the coil - no spar when the coil wire is held close to the block

I also checked the coil wire for continuity and that’s good.

So, I guess I should purchase a new coil and see what happens.

Unless there is something else I should try?

 

[FJ40Jim]

The correct coil is still available from Toyota.
I don't trust chinesium coils (as pictured) with Denso ignitor boxes.

 

[igotta40]

There should be a black wire from coil (-) to the side of the distributor, that is the ground wire for the ignition points. Replace that wire with a new one and see if your motor starts.

 

[greenbeasty]

Man I love this site!!

 

[Pin_Head]

I thought that you already tried swapping coil and ignitor? Something strange is going on if you have 2 “bad” coils in a row. I have only seen one fail and that one was abused.

 

[brooklyn]

Well, finally solved my "no spark" at the coil. I was finally able to successfully verify spark a the coil using Pin_Head's method. I then discovered the + side of the coil was getting power intermittently due to a loose connection. Once power issue was resolved, the truck fires up. My initial igniter seems to be fine, I did have the igniter and coil mounted upside down with the coil facing downwards. I did this as when I installed dual batteries and needed to move the coli/igniter. The coil wire would only reach the distributor cap if it was upside down. I did find a lot of rust inside the center pole on the coil and I am not sure the upside configuration was a cause. I have resolved this buying a longer coil wire for 99 cents.

Again the Pin_Head.

 

[greenbeasty]

Happy to see that resolved!!

 

[fcgadget]

Just went through hours of troubleshooting and questioning of my tools and understanding and finally checked the coil wire (to the dizzy).
It was the problem!

 

[Bbilbao]

This thread really helped me out. Thanks to everyone that contributed.