304 AMC backfire through the car

frankhense3 · 2025-10-02T23:13:49-0400

I have a 1973 cj5 304 AMC manual transmission. The tub is off and I am trying to get the engine to start. I am getting a backfire through the carburetor which suggests timing to me. I have the jeep at TDC and the picture #1 shows the picture I am using to get everything in the right place according to the picture. I noticed today that my rotor is not pointing to the distributor cap where I have the number one plug wire picture#2. My finger is on the #1 wire. This doesn't match the picture in relation to the cap screws. The rotor is pointing to the # 1 one spark plug. So I think I have the spark plug wires wrong. My question is should I put the plug wires as they are shown in the pic or is the cap orientation wrong to begin with?

Pic 2

Pic 1

Pic 3

77Jeep · 2025-10-02T23:42:38-0400

I think you have the distributor almost 180 out. it should be going through the exhaust or just have no power if its the way you describe

JEEPFELLER · 2025-10-03T00:03:20-0400

See post 41 in here https://www.jeepforum.com/threads/n...old-cj-running-again-for-the-farm.4446829/page-3?post_id=41394057#post-41394057

See the bottom of Post 44 in here https://www.jeepforum.com/threads/r...uilt-258-will-only-run-at-32-btdc.4499332/page-3?post_id=41897179#post-41897179

-----JEEPFELLER

Buster1 · 2025-10-03T09:14:36-0400

If you’re POSITIVE you’re TDC on the compression stroke, the rotor will be on the #1 position (or likely 1/4-1/2 inch prior (CCW) to the firing position if the motor has been timed).

Put the dist cap on with no plug wires.

Mark the tower with tape or something permanent that says “1” at the position the rotor is at.

Grab a wire and connect it to the #1 tower, then to the #1 plug.

Next move Clockwise on the rotor one tower. That’s #8. Grab a wire and repeat the above step connecting it to the #8 plug.

Keep going until you are done and you will be confident that your wires are perfect!

Fourtrail · 2025-10-03T09:52:00-0400

did you verify tdc #1 with a straw in the cylinder and not rely on the pulley, the balancers on older engines have been known to slip and the timing marks will no longer line up with tdc

frankhense3 · 2025-10-03T10:07:58-0400

Yes, I have confirmed TDC. I am using a whistle to make sure it is where it needs to be. Thanks for asking. I will confirm with a straw just to make double sure.

Fourtrail · 2025-10-03T12:18:42-0400

The whistle gets you on the compression stroke, but does not verify tdc.

devildog80 · 2025-10-03T15:49:28-0400

Looks like you are one cog off on the distributor clocking.

304 AMC backfire through the car

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