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Wrong Firing Order, But it Runs

Wrong Firing Order, But it Runs
A

Arc 21

Jeeper
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Location
Ranchos de Taos
Vehicle(s)
67 CJ5, 82CJ8
Kind of a strange first post here but I'm working on my project CJ8 with a AMC 304 V8 and I'm chasing down a problem with the motor not wanting to idle. I've had the carb off and cleaned and checked it and replaced the base gaskets. I then got to thinking coil and it was then that I noticed the plug wires are routed all wrong and the firing order is out of sequence. Now I'm surprised it ran at all considering that. One thought I had is maybe someone had put the distributor in 180' out of phase and maybe tried to compensate by moving plug wires around. Later today after work I'm going to change the wires back and see how it runs. In the meantime I'm looking for comments and insight on this and probably have a follow up coil question or two.
 
Welcome aboard, my first introduction to firing order was when I put the plug wires on in the wrong order many many years ago, it barely ran when I had it wired wrong


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Arc 21 said:
One thought I had is maybe someone had put the distributor in 180' out of phase and maybe tried to compensate by moving plug wires around. Later today after work I'm going to change the wires back and see how it runs. In the meantime I'm looking for comments and insight on this and probably have a follow up coil question or two.
Click to expand...

If the distributor was 180* off and they moved the wires around correctly, then it's no longer 180* off, and would be correct.

So have you corrected the firing order yet, if so how did it run?
 
jp360cj said:
If the distributor was 180* off and they moved the wires around correctly, then it's no longer 180* off, and would be correct.

So have you corrected the firing order yet, if so how did it run?
Click to expand...


I'm going to start working on it in an hour or two.

Another possibility has occurred to me, maybe the timing chain slipped a tooth and the PO moved the wires for that. If it won't run with the correct firing order I'll pull the dizzy for a look and probably the timing cover too as I have to replace the water pump anyway.
 
Or the dizzy was installed 1 tooth out of correct alignment, of the rotor to cap contact.
LG
 
If you were to look at my dist. you'd think the wired were wrong, they are not. The HEI dist. and the power steering pump wanted to occupy the same space when timed correctly, so the Dist. was jumped one tooth to gain space for timing. This is a fairly common thing to do. But Mr. Bass came up with a better way. He put a longer belt on the Power Steering pump to move it out of the way. Genius move, but he is known for that sort of thing.
 
Arc 21 said:
I'm going to start working on it in an hour or two.

Another possibility has occurred to me, maybe the timing chain slipped a tooth and the PO moved the wires for that. If it won't run with the correct firing order I'll pull the dizzy for a look and probably the timing cover too as I have to replace the water pump anyway.
Click to expand...


Yesterday I did put the wires in the proper sequence and it would not run. The drive gear on the distributor was in good shape. I had a heck of a time getting one of the long bolts out of the water pump so that slowed me down and I ran out of time before I got to pulling the timing cover. Maybe today I can get to that. I'm expecting to find a very loose chain but we'll see. Thanks to all for your input on this so far!
 
Arc 21 said:
Yesterday I did put the wires in the proper sequence and it would not run. The drive gear on the distributor was in good shape. I had a heck of a time getting one of the long bolts out of the water pump so that slowed me down and I ran out of time before I got to pulling the timing cover. Maybe today I can get to that. I'm expecting to find a very loose chain but we'll see. Thanks to all for your input on this so far!
Click to expand...

What was your process for correcting the firing order? Did you find TDC on compression stroke, use the terminal the rotor was pointing at for #1, then continue clockwise with the correct firing order?

Here's the correct AMC V8 firing order (note that the position of the #1 cylinder to the distributor is irrelevant. It much point to the same terminal as the rotor when #1 is @ TDC compression. That will get you close enough to start and dial in the timing):

firingorder.gif
 
Another possibility, PO of my 80 CJ7 said 3 mechanics couldn’t figure out why the 350 wouldn’t idle.When it died on me on the way to the shop I limped it home.While backing into my shop it wouldn’t go into gear without dying.Turns out it was the stall converter going bad the whole time and finally gave it up.
 
Arc 21 said:
I'm expecting to find a very loose chain but we'll see. Thanks to all for your input on this so far!
Click to expand...
You can test the timing chain slack by turning the crank and watching the rotor for movement.
Set to TDC, "0"
Turn the crank backwards (left)
Watch for rotor movement
When the rotor moves stop, then check the timing scale
If you have 6-7 degrees or more you have too much slack.
 
Look for a PN on the cap. Who made the cap?
Can you post a picture show'n the terminals from the inside?
Please post a picture shown details of your distributor with spark-plug wiring to the plugs.
Have you ck'd the compression of each cyl?
LG
 
Arc 21 said:
I don't know what that is, if you mean the dist. cap it looks to be just a run of the mill stock cap for my stock distributor.
Click to expand...



Cross fire caps look normal, but are made so that the wires for the right are all on the right side of the cap, and the left are on the left. You should be able to tell by looking at the inside of the cap. They are used to “clean up” the engine compartment.
 
What was the firing order when it was running?


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I got down to the real nitty gritty this morning and pulled the timing cover off.It was worse than I thought, I've never seen a timing chain with so much slop in it. WAAAY beyond the limit. So I'd say once the new parts go in the dist. can be timed and the wires replaced in the right squence and hopefully problem solved!
 
While your in there, switch your timing gears for a matched set.
 
jp360cj said:
What was the firing order when it was running?


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Click to expand...

Sorry I'm late on this. Each wire was moved ahead two positions on the distributor cap, so same firing order in a sense, just advanced by two. Turns out someone did it to keep it running with a badly stretched chain.

Interesting that the chain was let go like that and a cobby repair was done when the rest of the motor seems quite strong. At some point somebody stopped loving this Jeep.
 
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