Motor not firing

[rdf]

I just finished putting the engine and all it's components in my 73 'Cuda but when I crank it over, it doesn't fire....just sits there and cranks.  Here's a little backstory on the car....The motor is a 493 with an MSD 6AL ignition and an MSD Pro Billet distributor & coil.  I put in brand new fuel tank and fuel and brake lines along with a new Mallory 110 Series Fuel Pump as well.  It's got a Holley 650 Double Pumper on it with no spacer.  I had to make my own spark plug wires due to having Headman Headers and log/angle boots wouldn't work.  The wires are MSD Street Fire.

Here's what I've done:
1 - I initially thought it was a fuel problem but I verified that the pump is installed correctly and the lines are also hooked up properly.  I even used a siphon and got gas coming out of the fuel line at the carb.

2 - Took the coil wire off at the distributor and made sure I got spark.  I even tested for spark at the #1 cylinder and there's spark (blue in color).

3 - Timing.....this is where I think my problem is but I am not sure.  Firing order is 184365721 and it goes counter-clockwise on the cap.  I believe I found TDC by pulling the #1 plug and feeling for the burst of air when someone bumps the ignition.  I can't say with 100% accuracy that I felt the top of the piston (with a small screwdriver) but I do believe what I felt was it.  After that I pulled the distributor cap off and made sure the rotor was pointing at the #1 wire on the cap.

4 - Engine will fire if starting fluid is used but only for a second or so.  Car won't fire if I pour gas into the carb and try to start it.

So after all that, it cranks but doesn't fire.  I'm at a loss as to what to try next so any advice/tips that anyone can give me, I would greatly appreciate.  I have a bunch of short videos that kinda show what's going on but I can't upload them here.  This video shows what it was doing before but now I can't even get it to fire at all:

[Scooter]

If you have fuel, fire and compression I'd say you are on the right track with timing.

If the dizzy is close to #1 on compressions stroke, you should be able to get it to spin.

I recommend verify you are on the compressions stroke first.

On the exhaust stroke you will still feel some pressure.

Compression stroke will push your finger out of the spark plug hole.

GL

[rdf]

Yeah I'm thinking the same thing but again, have run out of ideas.  I will probably pull off each wire, one at a time, and check for spark, just to make sure I didn't mess any of them up when I made them.

[dodj]

Well, based on how I read what you wrote...
My first move would be to remove the bowl plugs and verify fuel level. I would then actuate the throttle and verify that fuel comes out the venturi nozzles.
Then I would manually rotate the engine with #1 plug removed with my finger in the hole and ensure I was at TDC firing stroke.
Then I would remove the cap and check the rotor orientation to make sure it was lined up with the wire going to #1 cylinder.
Then  i would verify the reluctor gap. 0.008
If everything above is done and verified/adjusted and still no start, I would suspect the ignition unit.
Just my 

[JonH]

Where is the timing mark on the balancer when you think you have have the rotor pointing at #1? Looking at your picture your timing is retarded. The rotor is pointing towards the valve cover bolt and #1 on the cap is a little forward of that. (#1 should be closer to where #2 is) At TDC the rotor should be about 15 degrees or so past the #1 plug on the cap. This is assuming that the MSD box is wired correctly and you have fuel. Try rotating the distributor while someone cranks it over for you. Based on your video and pictures, it appears you do not have enough ignition advance...

[rdf]

Well, based on how I read what you wrote...
My first move would be to remove the bowl plugs and verify fuel level. I would then actuate the throttle and verify that fuel comes out the venturi nozzles.
Then I would manually rotate the engine with #1 plug removed with my finger in the hole and ensure I was at TDC firing stroke.
Then I would remove the cap and check the rotor orientation to make sure it was lined up with the wire going to #1 cylinder.
Then  i would verify the reluctor gap. 0.008
If everything above is done and verified/adjusted and still no start, I would suspect the ignition unit.
Just my 

What is the reluctor gap? 

Where is the timing mark on the balancer when you think you have have the rotor pointing at #1? Looking at your picture your timing is retarded. The rotor is pointing towards the valve cover bolt and #1 on the cap is a little forward of that. (#1 should be closer to where #2 is) At TDC the rotor should be about 15 degrees or so past the #1 plug on the cap. This is assuming that the MSD box is wired correctly and you have fuel. Try rotating the distributor while someone cranks it over for you. Based on your video and pictures, it appears you do not have enough ignition advance...

Finding the timing mark on the balancer is the hard part as it's pretty tight quarters in there and I don't have the best eyes, lol.  I will look into this when I have a chance this week and see what I can make of it.

[HP2]

Air, fuel, ignition, compression, in the right amounts, at the right places, at the right times are what makes an engine run.

You checked for gas at the lines, great. Does it squirt out the carb when the throttle is activated?

You checked the coil for spark, great. Does it fire at the plugs?

You obviously have compression if you felt the pressure of the cylinder stroke.

If engine fires with starting fluid when cylinders are full of vapor, then its capable, there is just a part of the formula that is off.

Agree with you it may be timing.  Difficult as it may be, bring the timing marks up to TDC and check piston position and rotor position. If they are close, it should fire.

[dodj]

Well, based on how I read what you wrote...
My first move would be to remove the bowl plugs and verify fuel level. I would then actuate the throttle and verify that fuel comes out the venturi nozzles.
Then I would manually rotate the engine with #1 plug removed with my finger in the hole and ensure I was at TDC firing stroke.
Then I would remove the cap and check the rotor orientation to make sure it was lined up with the wire going to #1 cylinder.
Then  i would verify the reluctor gap. 0.008
If everything above is done and verified/adjusted and still no start, I would suspect the ignition unit.
Just my 

What is the reluctor gap?


The reluctor gap is the space between the 'star' wheel under your rotor and the magnetic pick-up. It's that pulse that tells the ecu when to fire the coil.

[rdf]

Air, fuel, ignition, compression, in the right amounts, at the right places, at the right times are what makes an engine run.

You checked for gas at the lines, great. Does it squirt out the carb when the throttle is activated?

Yes, I can definitely see gas coming out of the jets when I push the throttle either manually or at the pedal.

You checked the coil for spark, great. Does it fire at the plugs?

I have only checked 2 of the plugs but I plan to check them all later today....I'm with you in that I need to rule out all possibilities, even the oddball cases.

You obviously have compression if you felt the pressure of the cylinder stroke.

If engine fires with starting fluid when cylinders are full of vapor, then its capable, there is just a part of the formula that is off.

Agree with you it may be timing.  Difficult as it may be, bring the timing marks up to TDC and check piston position and rotor position. If they are close, it should fire.

Thank you!

[rdf]

The reluctor gap is the space between the 'star' wheel under your rotor and the magnetic pick-up. It's that pulse that tells the ecu when to fire the coil.

Gotcha....learn something new every day! 

[Scooter]

. . .
What is the reluctor gap? 

Just adjusted mine this last weekend. See photo below. It's the gap between the star gizmo on the left and the magnetic pickup on the right in your dizzy.

Try to ensure the gap is even from top to bottom as well. A folded dollar bill is darn close to perfect gap. 



GL!

[CU-DUH!]

@rdf , did you get your motor to fire?

[Chryco Psycho]

Seems lik eyou are on the right track with Ign , it may want a lot more advance than where you have it set though , the spark needs to be there Before the piston gets to TDC
The other question is fuel , it may be flooded or simply too lean to fire up especially if you do not have a choke .

[ek3]

bet  it's 1 notch out ......  bring it back to tdc.  on the compression stroke and  check your timing mark on the balancer and it should be before tdc.if not ,  take out dist. drop it in rite... 

[MoparLeo]

As most of us know, there is no such thing as one notch out on a Mopar distributor as the oil pump drive gear is not on the distributor shaft on the distributor like GM is. Only a blade like a standard screw driver so either it is correct or 180° out.
Question, I am guessing that you did not personally build this engine. Has it ever been run before or just taken off the stand and installed ? You have a lot of non factory items that you are working with so it makes diagnosing your problem a little harder.
When you test things only make 1 change at a time.
Never pour gas down the carb or anywhere else but the gas tank. Spilled fuel can cause a fire and/or just foul the plugs. Always have the proper fire extinguisher handy.    Do your starting outside of the garage or enclosed area just in case of fire (it does happen !)
Cranking a new engine( or even a used engine) to prime the pump, fill the fuel bowls, check timing etc... just causes a LOT of premature wear especially the bearings.
The oil pump should be primed with a drill or similar Before startup to make sure that there is plenty of lubricant on the bearing surfaces immediately. You would need to remove the oil pump drive gear sitting on the cam and use a hex rod of the proper size and length.
Fill the fuel bowls thru the bowl vents with the proper sized hose/funnel and verify that the accelerator pump is functional.
Make sure you have a fully charged battery.
Hopefully you have a Factory Service Manual to help guide you thru some of these procedures.
Go back and verify all of your connections for being tight and in the proper place/sequence. Check all electrical grounds.
Most times it is something that is relatively simple so just be thorough and safe.
An extra set of hands and eyes are invaluable especially if they have some experience in this area.