351w not firing but cranks and sparks

As long as the firing ORDER isn’t 1-2-3-4-5-6-7-8… :slightly_smiling_face:

No, it’s 1-4 right (passenger) and 5-8 left.

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That’s better… :slightly_smiling_face:

I concur with the advice that @Nevada_545 stated previously. After you get the plug wiring figured out you will need to reinstall the disty correctly. The incorrect alignment is causing the fuel to be pushed out of the carb instead of being sucked into it due to misfiring.

He circled what appear to me to be the bowl vents in the first post. The intake isn’t going to push gas out the float bowl vents. It would be blowing back from the venturis from backfiring. There may be more than one issue…

I see your point @TwinTurbo. I guess the needle valves could be sticking open due to corrosion. The disty still could be installed 180 out.

When the automatic choke is closed the throttle is pushed open to the fast idle position for starting and in that case back firing ignition could throw fuel up from the bowl and out the vents. Is the choke plate closed in the picture?

Okay I went back in 351 time at TDC, checked compression with a finger over the plug to confirm pressure on the upswing. Spark is still present, because now I have backfire up the throat, still not starting fully but actually seeing that I feel better.

So now it’s timing right? Retard or advance for start or am I looking at too much fuel? I am pretty sure the egr valve is deleted but I will admit I’m not sure where it is. There is a vacuum valve on the drivers side header that might be the egr.

First my bad for getting the side wrong on the firing order, I was going by memory and it has been a looong time since I replaced ignition wires on a Ford V-8. For some reason I thought #1 was on the drivers side, but I stand corrected.

Now for the timing. First you confirm that you are on the compression stroke on the #1 cylinder. I hope you are using a ratchet and socket to check this and not the starter motor. Personally, I’d use a compression gauge instead of my thumb, but use what you got.

For the firing order, if you still have the original intake manifold laying around, the firing order will be cast in it on one of the front runners. Confirm the firing order is correct. Now with the engine set to the timing mark for the correct timing at idle with the vacuum disconnected, confirm that the rotor is pointed at the post for the #1 spark plug wire. This should be a few degrees before TDC. If it is not pointed directly at the correct post, the distributor could be installed a gear off which could put the rotor between two posts when firing. This is one of the most common reasons for the issues you are seeing.

The distributor must be lined up correctly. You can’t just turn it to compensate of you miss the right gear. On some distributors, there is a pair of marks, one on the gear and one on the body. You align these marks which will move the rotor off the mark, but as the distributor drops into place, the rotor will rotate to the correct position.

Now for the last step. Your HEI distributor probably has a eight vanes around the shaft just under the rotor. There should be a reluctor, aka ignitor, that one of the vanes is pointed to. On the ignitor, there will be a line that the vane should be aligned with. Turn the distributor so the vane and the line on the ignitor align perfectly and then clamp down the distributor. Your timing should be within one degree of spec.

Got it! Had to advance a few degrees adjust the throttle and idle. I will say I added my tach wire to it this time to fill out all circuits and for people that look into wiring I used the RED wire not green with blue. Both show 12v as a switch but I believe RED cranks.

Of course I’m trying to get plug wires straightened up the five pulled apart so that’s getting replaced. The higher distributor puts tension on the wires and I just want to get some slack.