1979 FJ40 won't start - Process of elimination to get it going (2 Viewers)

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Signal Mountain, TN
Semi-new FJ40 owner here. I have a 1979 FJ40 with a rebuilt 2F. I've had it for around 4 months and have used it as a daily driver with no issues. Dropped the kids at school yesterday and pulled in the driveway. Went to start it up later in the day and it won't turn over.

I've checked the battery, changed the oil a couple of days prior (not going to prevent it from starting, but figured I'd mention it) , checked fluids, checked cables (distributor) and hoses (vacuum lines, etc.) under the hood and don't see anything loose or out of the ordinary. It cranks, but won't turn over.

My question is where should I start in the process of eliminating parts that may be preventing it from running? I use to own an '85 4runner that I tinkered with, but since then I haven't really worked on an older vehicle.

Any help is appreciated. It makes me sad to just see it sitting in the driveway! Hoping it's a simple fix...
 
Not an expert here. I have a similar year model May 79.
Can you be more specific on the starting sound?
So you don't get a click sound?
The truck tries to crank through the starter but will not catch(so to speak)?

Is the sight glass in the front of the carb showing gas? Should be up to the halfway mark I believe.
 
Slow crank or normal speed ? Put a new batt in and see what you get, if that starts then I'd check alt. If new batt does not start then I'd look at coil.
 
Firstly: won’t turn over means the engine doesn’t spin: engine cranks and turns over are the same thing. I think you are meaning it turns over but won’t start or try to start? (If it’s not spinning the engine, skip to last paragraph).

So on the assumption you turn the key, starter engages and starts cranking the engine over, it just isn’t starting/firing/sputtering/etc.
As said, is there fuel in the sight glass on the carb? (Is it a factory Aisin carb?) if no fuel, is there enough in the tank? Don’t go by gauge or “should be enough”; add 5 gallons.
If fuel, is there spark? Check this by pulling a plug and wire and ground the plug electrode with wire connected and crank engine over. Hold it with rubber handles pliers or you’ll get a jolt!
Then report back.

Now, if you turn the key and the engine isn’t trying to spin at all check:
Charged battery? (12+ volts)
Is it clicking?
Check battery cable connections: both ends of all cables.

Then report back.

Also, is it all stock? Stock distributor and ignition system (stock engine?!), desmogged?
 
Look at the Engine Fuse to verify it isn't blown. Maybe the distributor plug has a bad connection?
Always start with the simple things and work your way in.
Fuel, Spark and Air is all that's required to make it run.
 
Thanks for all the suggestions thus far. Yes, turns over but wont start. Fuel in the tank, yes. Fuel in the carb window, yes. Not sure of the make of the carb (image attached). Performed the spark test by touching one of the distributor wires to the block and cranking. No spark. Just got done replacing the coil with an aftermarket version from AutoZone. Still nothing. Engine was taken out and rebuilt by previous owner. original 2F to the vehicle, but some exterior components have ben replaced.

With all that info, where should I go from here?

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It's on the left lower dash right at the door seal assuming it's a factory wire harness and not Painless Wiring or the like
 
@POTATO LAUNCHER would a burned up fusible link cause this?
@adamdsgn search fusible link here for more info/pictures. If that's burned up that could be the issue.

I believe the M is a designation for a carb rebuilt by Mark A. here on the board, very good thing. Any paperwork indicate a rebuilt carb?
Engine fuse is 3rd fuse up from bottom in fuse block on drivers kick panel. See below

I had a new alternator from a local auto parts store be dead out of the box before. Just a thought.
 
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@POTATO LAUNCHER would a burned up fusible link cause this?

I believe the M is a designation for a carb rebuilt by Mark A. here on the board, very good thing. Any paperwork indicate a rebuilt carb?
Engine fuse is 3rd fuse up from bottom in fuse block on drivers kick panel. See below
I'd think a fuseable link on the 79 40 and 55 is still a single element to main fuse panel. Would be a good place to look though.
 
Did you touch just the end of the plug wire (spark plug end) to a bare metal part on the block? You will need to have a spark plug in the end of the wire or stick a screwdriver in then to touch the electrode, then hold screwdriver 1/4” from a good, clean metal ground.

Carb: ok, stock so that’s good. When you turn the key on but don’t try to start, do you hear a “click” from the top rear of the carb?
 
Have you checked for power to the coil? If so, is voltage good?
 
I’ve had Chinese parts bad in the box And go bad in a few months. Try another.
 
Engine fuse is good. I'll have to see if I can't borrow a multimeter to check the power to the coil. I'm going to take the distributor cap off today. What should I be looking for? Also could it be a grounding issue?
 
Engine fuse is good. I'll have to see if I can't borrow a multimeter to check the power to the coil. I'm going to take the distributor cap off today. What should I be looking for? Also could it be a grounding issue?
I am in North Chattanooga and have a multimeter if you need to borrow it. They are cheap too from Amazon or parts store. Just moved to the area and have a 62 and a 40 project.
 
Update.

Successfully jumped the coil by bypassing the resister on the firewall. Vehicle started but only momentarily. It looked like the resister was the problem because it was not getting enough voltage to the coil.

Replaced the resister, but in the process of putting everything together the everything together, the coil wire from the coil to distributor stripped off. Replaced coil wire/spark plug wires.

All voltage was correct from coil, igniter, resister, battery, etc. Still won't start.

I ordered the D.U.I. kit from Summit (Davis Unified Ignition 80820BK Davis Unified Ignition Toyota Street/Strip D.U.I. Distributors | Summit Racing - https://www.summitracing.com/parts/DUI-80820BK). Not sure if the distributor is the issue. Cap is new-ish, but the distributor looks to have some corrosion inside.

From what I've read the D.U.I replaces the distributor and remedies some of the issues with the electronic ignitor, coil, etc. Who has installed one of these before? Difficulty, additional parts/harnesses I may need, etc.? Any help is appreciated. TIA.
 
Update.

Successfully jumped the coil by bypassing the resister on the firewall. Vehicle started but only momentarily. It looked like the resister was the problem because it was not getting enough voltage to the coil.

Replaced the resister, but in the process of putting everything together the everything together, the coil wire from the coil to distributor stripped off. Replaced coil wire/spark plug wires.

All voltage was correct from coil, igniter, resister, battery, etc. Still won't start.

I ordered the D.U.I. kit from Summit (Davis Unified Ignition 80820BK Davis Unified Ignition Toyota Street/Strip D.U.I. Distributors | Summit Racing - https://www.summitracing.com/parts/DUI-80820BK). Not sure if the distributor is the issue. Cap is new-ish, but the distributor looks to have some corrosion inside.

From what I've read the D.U.I replaces the distributor and remedies some of the issues with the electronic ignitor, coil, etc. Who has installed one of these before? Difficulty, additional parts/harnesses I may need, etc.? Any help is appreciated. TIA.
They (DUI) recommend powering the DUI from the battery using a relay so maybe a relay and some wiring. Others have used the existing coil power lead and say it’s fine. Up to you to decide what you prefer.
 
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D.U.I. successfully installed. Now getting spark, but still not firing. Poured fuel into the carb with positive results (firing momentarily, but not running consistently), but the throttle pump (?) on the cab doesn't seem to be feeding fuel into the carb... Needless to say at this point it's a fuel issue. There is fuel in the carb window, but the car isn't getting fuel to fire.

And... discuss. Where do I got from here?

Take the carb out, disassemble and rebuild?
 

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