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351w not firing but cranks and sparks

Hi, I’ve been trying to get my truck to start up after putting a airgap intake on and replacing the coil and distributor with an hei distributor, reusing the edelbrock carb that was on it. It cranks, has spark, plug 1 is set to cylinder 1 at TDC, plug wires are a year old and plugs look fine. The issues is in the carb it seems, when it cranks fuel is pumping but blast out of the “vents” the rectangular parts before the throats but after the bowl. So it’s a fuel issue in there I figure. I pulled the lid off of the carb yesterday not full disassembly but just to shake the floats down. Battery is dead after multiple attempts recently. So I’m just seeing if anyone has had this, has suggestions or knows the name of those windows are.

It pops straight up no fire just fuel. Also I’m using the 351w firing order 1-3-7-2-6-5-4-8

How did you test the spark? Also put a vacuum gauge on the intake manifold and tell us how much vacuum you have. And recharge that battery.

Pull plugs and check compression and look at the plugs. Are they wet? Dry?

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There are several ways to use the correct firing order and still get the engine out of time. The direction of the rotor turning and the numbering sequence of the cylinders come to mind.

I do agree with @MikeInNH 's suggestion to look at the plugs and check the compression.

The last time I had fuel geyser out of the vents, the floats were stuck open due to the car sitting for so long and bowls empty. Floats down would be bad, then they wouldn’t be closing when full. Did you tip the carb upside down when working on the car? I would work the floats up/down to be sure the needle is not sticking.

Did you be sure to remove the ballast resistor for the coil when you installed the HEI? It needs solid 12V. Not related to this issue but just to eliminate other issues once you get past the geysers.


Not going to lie the bowls were pretty low when I looked in, I did peak at the bottom when I removed the carb. It sat for about two days to the side. So is there an easy way to clear the needles? I have been feeling the fuel is blocked at that point.

When I say easy I mean not a full carb break down.

Watched it and shocked myself, because I wasn’t paying attention and held the plug not boot.

You need a spark tester.

The first thing you can try is to rap on the float bowls with the handle of a screwdriver. Don’t go insane but a sharp rap can sometimes dislodge the needle(s). Otherwise, you may need to take off the top of the carb and work the floats by hand. Lightly, you don’t want to bend the arrm and change the float height setting. If you get this far, make sure the float isn’t hitting the stop, preventing the needle from fully seating. Low probability since it was working ok before but worth observing to make sure. Watch the needles to see them move. Spray some carb cleaner in there while upside down and work them by hand. If you’re careful and lucky, you might save the gasket but it might pay to have a rebuild kit on hand in case you need to replace the gasket. Sometimes you can buy just the primary gasket set and not full rebuild kit.

Or just a timing light

That would show him that he has a spark, but not the strength. He changed out the entire ignition system, and that may be where the problem lies.

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Good point.

Had the plug out and watched it spark

Quick update for anyone following.

I got a feeling to consider the firing order after watching a rebuild on YouTube of a f250 where they installed a 302 cam in the 351.

I’m not the first owner and thought this truck has been opened before so I tried the 302 firing order and almost got it started. So then I know there is discussion of an alternate firing order in LS engines, not sure about that working in ford cases.

You installed the distributor with cylinder # 1 at TDC on the exhaust stroke, it should be at TDC of the compression stroke. The distributor is 180 degrees off.

When you changed the firing order to the 302 four of the cylinders became timed right but that is not the solution.

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Couple of things come to mind here. The fuel issue looks like either the floats are set too high and need to be lowered, the needle is missing, or the fuel pump is putting out too much pressure.

On the timing side, you could be TDC on the exhaust stroke as mentioned by @Nevada_545 or your timing order is wrong. One thing that some people don’t know about Ford timing order is that the cylinders are numbered 1-4 on the drivers side and 5-8 on the passengers side. Most other V-8 engines number odd numbers on the drivers side and even on the passenger side.


Wait seriously? 1-4 drivers side 5-8 passenger side. If this is true what the hell?

Could it be that the problem has been found @Grimace?

I just typed in 351w firing order, got this:

Now, can anyone tell me why Ford would choose to number their cylinders like that on those engines? Aren’t almost all V8s numbered 1/3/5/7 on one side, 2/4/6/8 on the other, with 1 being closest to the front?

edit - I guess all Fords were that way…I forgot that from the service station days…

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