HELP Bronco will not start

[ACE]

OK heres the history:
Drove it almost everyday for the last 4 years, never a starting problem.
After work I parked it in the garage, next morning it just cranked and cranked,
never even tried to fire. After work, checked for fuel (1/2 tank) getting to the carb, Yes, checked for spark at coil, all plugs, yes, pulled #1 plug, got engine to TDC, dist. rotor pointed to #1 on the cap. Pulled valve covers, everything looked OK, push rods, rocker arms all moving up and down so I think cam is not broken. Only thing I can think of is the timing chain and gears may have sliped making it just out of time to not start.
Almost forgot, I bought a new ignition control box, (the right one after two tries) didn't help.
Had 2 guys that know alot about engines take a look, no help no solutions.
So I'm leaving this up to you Bronco gurus for help.
Thanks for reading this long post.
Joe

[Broncrick]

After everything you checked, I also would lean towards the chain

[Daddy4zack]

Did you ever pull out the distributor?

[ACE]

Did not pull the dist. thought about it but tried to turn the rotor by hand, it didn't turn and tried to hold it while the engine was turning over and could not hold it, so I throught it was ok. I'll pull it after work today and let you know whats up with it.

[Delta 4 Wheel]

Although timing chain breakage is rare, it has obviously happened in the past. In your case, I would doubt it is the chain because you drove it in fine the night before.

If the timing chain had slipped you would find a few things: 1. Air coming out of the carb. This happens when the intake valve does not close quick enough and the piston pushes the air out instead of compressing it. You would also hear a funky thump-thump out of the exhaust. It is hard to explain, but you would know that is just not right. You can do a couple of checks for this. Set the engine at top dead center. Pull the passenger side valve cover off and verify that the number one cylinder has both valves equally shut. An easier way would be to check compression in the cylinder, but I like the full-proof way of looking at it with the cover off. If both valves are equally closed while the balancer is at TDC, it impossible for the chain to be slipped.

Another thing to check after this would be the timing. While someone is cranking it over, have the timing light hooked up and make sure it is set to 12-14 deg. btdc.

Verify that you are getting spark to all cylinders EQUALLY strong. You might have piss-poor spark that is not enough to ignite the fuel.

I would also temporarily install a point distributor and standard coil to isolate the ignition system from the problem.

[ACE]

I'll start with checking to make sure the valves on #1 are both closed today, and timing. Compression was 90 low to 110 high in all cylinders (forgot to mention that) 180,000 miles on engine, never been worked on.

[mtnbronco]

I noted you checked spark at coil, did you check at the plug?
Are you running OEM ignition?

Fords have many issues with their ignition systems. I lean toward it being an ignition issue. A mechanical problem you should of noticed while driving the night before. ie funny noise, running ruff, or lack of power. Also keep in mind that you can easily fuel foul the spark plugs which will prevent it from firing. You can tell by pulling one and it will be wet in appearance and smell of fuel.

[ACE]

I checked for spark at all plugs, all fired at the wire, pulled the plugs and had fire through the plug gaps, plugs smelled of gas and wet so maybe spark asn't hot enough, how do I check, changed in new ignition control box, maybe a bad coil, dist.?
Off work now 3:30, talk at ya tomorrow. Nobody does anything tonite except think about my problem OK

[Delta 4 Wheel]

I really don't know how to "officially" check for spark, but you should see a nice spark from the electrode to the tail of the plug. It should be strong and make a light snapping sound. Ground the plug threads to the head while you are checking the spark.... I am still leaning toward electricity being your problem...



Have you hit the throttle and looked to make sure the accelerator pump is shooting fuel into the carb?

[ACE]

I didn't get to work on the Bronco last night, other comittment came up.
I'm off on Friday so I got 3 days to figure this out.