Ignition? (3 Viewers)

[Tigger72]

What am I missing? (1972 fj40 1f) Here is the story and what I've done.

In the beginning, it was Running well, after a drive with some washboard, it stopped wanting to idol, but at higher rpms it still ran well. Fix from the past was points adjustment as they slipped closed. Checked, they were tight so i adjusted to .018" (.45mm), barely started, idoled, and ran super rough. This is where we have lived for a while, and no matter what i did, it ran rough to the point where i couldnt drive it. But where we are now is it won't pop or start. What could the issue be?

Here is what I have done so far. What am I missing to solve this issue? (I did take this opportunity to do some Tune up items also)

Carb rebuild kit (no jets)
Adjusted float
Fuel filter
Valve adjustment
Compression check (120-125 ish on all)
New points
New coil
New cap/rotar
New condenser on distributor
Readjusted points
Static timing adjustment (BB to right before the points open on the scallop with rotor pointing at #1) because it won't start
Cleaned all ignition wire connections and checked ohm for busted wires
Checked plug wires (6000ish ohm)
Took out plug 1 and held to motor for ground, no spark.
Vacuum lines checked and evap control detached tested/reattached

What could of gone down so fast, changed with the point adjustment, but now degrading and not giving any elec for spark? A combo of issues? Something i missed? Something i did incorrectly?

Thanks for your thoughts!

 

[CruiserInProgress]

No spark at your plug suggests an ignition problem at a minimum.

To better isolate the no spark symptom, check for voltage (7-12v) at your coil (+) terminal while your key is in the start and run positions.

If no, your problem is upstream (ignition switch, wiring, ballast resistor, etc).

If yes, your problem is downstream (coil output, coil wiring, primary lead, points wiring, etc.)

 

[Tigger72]

No spark at your plug suggests an ignition problem at a minimum.

To better isolate the no spark symptom, check for voltage (7-12v) at your coil (+) terminal while your key is in the start and run positions.

If no, your problem is upstream (ignition switch, wiring, ballast resistor, etc).

If yes, your problem is downstream (coil output, coil wiring, primary lead, points wiring, etc.)

Thank you! and lets start with something you said of interest. Today I put a volt meter on the + and - posts of the coil with the ignition in the "on" or eun position. I didnt test in the poisition where it would turn the starting motor. It read at the high side of 4 volts. As mentioned earlier, the coil is new. The one I replaced was only 2 years old. I checked the resistance in the plug wires and coil to cap wire and they seemed good. Is the 4 volts from the 2 posts on the coil a tell? Or should I go + on coil to a different ground? If 4 volts is low, where could I trace that issue? The ignition switch isn't that old. It was replaced in the last 8 years with few miles in between. I checked resistance between many places in the system and didn't find any real restrictions.

 

[Tigger72]

Thank you! and lets start with something you said of interest. Today I put a volt meter on the + and - posts of the coil with the ignition in the "on" or eun position. I didnt test in the poisition where it would turn the starting motor. It read at the high side of 4 volts. As mentioned earlier, the coil is new. The one I replaced was only 2 years old. I checked the resistance in the plug wires and coil to cap wire and they seemed good. Is the 4 volts from the 2 posts on the coil a tell? Or should I go + on coil to a different ground? If 4 volts is low, where could I trace that issue? The ignition switch isn't that old. It was replaced in the last 8 years with few miles in between. I checked resistance between many places in the system and didn't find any real restrictions.

Also, is the "ballast resistor" the one attached to the post with the power that attached to the box attached to the + side of the coil? I couldnt find that in my FSM.

 

[CruiserInProgress]

The test I mentioned should measure voltage from the coil (+) to ground, which you should still do just to verify voltage there is adequate, both in the ignition run and start positions.

But, if you see a drop across the coil (+) to coil (-) while in the run position, that would indicate you have some level of power to your coil.

About your ballast resistor question, the ballast resistor might look like a ceramic block. It would have one terminal connected to the ignition switch via your wiring harness and the other terminal would be connected to the coil (+).

The purpose of the ballast resistor is to reduce the voltage to the coil and points to keep them from burning up while running continuously.

Getting back to your no spark issue, make that voltage measurement at coil (+) to ground. If that looks good (7-12v), you might verify you have spark coming from your coil when cranking.

To do that, locate the lead coming out of your coil. Pull that primary lead from the top of your distributor and clamp it so that the end is close, but not touching the engine block and turn to ignition run. This will simulate a spark plug, without involving the points or cap. Try not to zap yourself!

Oops, I may have missed a step. I think you also have to briefly touch the coil (-) to ground to simulate points and make a spark via the coil directly.

 

[Trollhole]

Your idle solenoid is not getting 12v. Make sure you can hear it click. Check the engine fuse. Make sure you have a good engine ground and that all your grounds are good. Run a 12v jumper straight to the positive side of coil and crank. Make sure your cap and rotor button are correct. Make sure contacts on points are correct and that it hasn't slipped out of the pocket.

 

[Living in the Past]

Has a vacuum leak been suggested? Have had that happen when engine stops idling all of a sudden.

 

[Tigger72]

Your idle solenoid is not getting 12v. Make sure you can hear it click. Check the engine fuse. Make sure you have a good engine ground and that all your grounds are good. Run a 12v jumper straight to the positive side of coil and crank. Make sure your cap and rotor button are correct. Make sure contacts on points are correct and that it hasn't slipped

No spark at your plug suggests an ignition problem at a minimum.

To better isolate the no spark symptom, check for voltage (7-12v) at your coil (+) terminal while your key is in the start and run positions.

If no, your problem is upstream (ignition switch, wiring, ballast resistor, etc).

If yes, your problem is downstream (coil output, coil wiring, primary lead, points wiring, etc.)

So volts coming into the ballast resistor is 10v and out to the + on the coil is 5v. Is that to low? I don hear the cellunoid click. I did take the resistor off and clean it up a bit and check the wire to the + post. Seems good.

 

[Tigger72]

Has a vacuum leak been suggested? Have had that happen when engine stops idling all of a sudden.

Yah... this was an early rabbit hole for sure.

 

[pb4ugo]

So volts coming into the ballast resistor is 10v and out to the + on the coil is 5v. Is that to low? I don hear the cellunoid click. I did take the resistor off and clean it up a bit and check the wire to the + post. Seems good.

View attachment 3936707

10 volts seems low. What's the batt voltage?

 

[Tigger72]

10 volts seems low. What's the batt voltage?

12.2. Getting tired from the fruitless cranking... but still over 12. When I take the harness wire off the top post of the ballast, I get 11.9 volts at the wire. Reconnect and test again at top post and it's 10.5 when points are closed. And 11.8 when points are open. Shouldnt this say electricity it's fine? Could I have not staticly timed it well and timing be way off?

Mystery thickens. Put the cap back on after taking those measurements, pulled all the plugs and made a grounded test plug and checked to see if all wires had power and created spark. They DID this time. Put them back in and it started. SUPER SUPER ROUGH but now it started! I just dont get it. Ibdidn change anything. Could it be a Bad distributer and when I mess around with it, it fails or barely functions? Doesnt seem possible. So frustrated. Weak spark? Timing off still? Carb? I keep going back to what was the first change seen... a point adjustment. I feel like I've covered thar though. Gremlins!

 

[pb4ugo]

Run a wire from the batt to the idle solenoid and see if it clicks, as trollhole suggested. Leave it on there and see if it helps. I'd also guess the tming is off, but close enuff to run. Have a timing light handy. The carb is probably out of adjustment because you just rebuilt it.

 

[Tigger72]

Run a wire from the batt to the idle solenoid and see if it clicks, as trollhole suggested. Leave it on there and see if it helps. I'd also guess the tming is off, but close enuff to run. Have a timing light handy. The carb is probably out of adjustment because you just rebuilt it.

Tested that earlier, and heard it click. And also put my finger on it and turned the key to on and could feel and hear it click. I will try and run it with a jumper to the battery and seen if there is a slight voltage issue.

I also believe the timing to be off and guessing i didn't staticly adjust it close enough. If it starts again and I can keep it running im also going to shine the timing light in there and see how much the BB bounces around as distributor run out was also a suggestion, but that seems like it would come on slowly.

Thanks!

 

[pb4ugo]

If it clicks it's probably fine. The problem is you made wholesale changes trying to fix the original issue. So everything is a little off. When it's running can you give it a little gas, does it smooth out any? Confirm the sparkplug wires are in the correct position, confirm points are set properly. Get it running and check the base timing.

 

[Tigger72]

If it clicks it's probably fine. The problem is you made wholesale changes trying to fix the original issue. So everything is a little off. When it's running can you give it a little gas, does it smooth out any? Confirm the sparkplug wires are in the correct position, confirm points are set properly. Get it running and check the base timing.

Sorry for my lengthly post. Earlier on in this adventure, right after the carb cleaning (for my first large carb rebuild, I always have questioned myself about my work there) I did work hard on the idel mixture screw setting but it was still running rough enough it was hard to create change. BUT I did purchase an advanced timing light because besides the BB, I can't find any other markings so other than running smoother, I had no idea where it lived. Now i can set it to tell me whats up. I set it to 11deg BTDC. I think i Need to restart here in a mechanical way to eliminate questions of history. I tried a static setting process I found on the webs, but dont know if its the best process for this rig. Anyone have a process for that? What i did was:

Found BB (which should be 7 deg BTDC, close enough to start and run at 5,500 ft?)

Made sure it was on the correct turn of the flywheel because the rotor was pointing at the #1 post on the cap. (Is that the compression stroke?)

Adjusted the dizzy in the retard direction to right before the points opened. (Left side of the nearest flat face on the armature.)

Is that correct? Maybe the dizzy was removed at some point and it's a tooth off and I need to put something in #1 and find it's highest point?

Thanks for the help.

 

[numby]

You were running fine until the washboard road resulted in poor running followed by your points adjustment. Not sure what shook loose (wires, debris in tank or carb) but changing the gap also changes your static timing so you're probably off a few degrees if you didn't confirm things. Running better at higher revs means you're pulling in advance so I bet your base timing is retarded. Usually having things a bit retarded you just give up power. If it's a factory dizzy then start at 7º BTDC even at your altitude.

The points may also be pitted. I have had burned points refuse to idle but run fine-ish at higher RPMs.