Doesn’t want to start after tune up

I'll ask the obvious. Did you verify firing order? verify the cap is on correctly?

Great question! And yes, the obvious one. I made this cheat sheet of the distributor connections when I did the first tune up, and yes, I’ve checked the wires TWICE! (Against the sheet 😬) Take a look and see if I did something wrong. The cap only fits one way with the cutout on the side (I think).

Last time I saw that happened… The person putting on the spark plug wires on the cap incorrectly! When you look down from the top, the rotor turns counterclockwise, not clockwise!!

…make sure that the rotor finger is pointing at the pick up for number one on the cap with cylinder 1 on firing TDC

Did you remove the distributor?  If so, you may have reinstalled it 180° out of sync.  

Also, check to make sure that the outer ring of the vibration dampener has not spun.  

John

Of course, you have heard of the stock distributor pin shearing…. I had a case where it didn’t shear completely, but enough to significantly retard the timing…

So anyway - that’s another thing to look at, but if you do the timing checks, as suggested above, you will find if that’s the problem…

Anyway, my real point in is that a sheared distributor pin doesn’t ALWAYS result in your distributor not turning…. It can still get bound up, and your timing will continue to retard, until it eventually fails completely…. But until it fails, you are chasing a timing problem..  you reset it,  and then a week later you’re having the same paganism!

Good luck!

Rocky

With dist cap off and rotor removed have someone crank the engine while you watch for sparking at one set of points. If no spark make sure that all the connections to the point are not grounded. Some people think that both sets of points should spark but that is incorrect. Only the last set to open will arc. Let us know what you find.

...A 'Good' Condenser is there to keep the points from Arcing. A 'Clean-Break' of the Current to the Coil is necessary for a Healthy Spark, through the D. Cap to the Plugs. With 'Arcing' of the points, there is Not a Total Collapse of The Magnetic Field within the Coil, That Creates the Spark. The Spark is Not Healthy. Should be a 'Blue Flame'.

Everyone is putting in Their Guess, of Which of a Dozen Failers can Cause a 'PoP', without Starting.

This guy has a lot of Searching, Testing, work ahead of him.

That's as far as I'm going. Don't Test the Coil Improperly and Burn it out!!

MJ

...After a Tune Up?? Re-Gap the Points. The Rubbing Block on New Points Has to wear-in...Especially if the Block and Cam have Not been Lubricated. This Closes the Gap Up.

The advantage of Dual points. (Dwell Duration=Coil Saturation)

MJ

I have found that the Ford dual point distributors that use the same design points cam (Boss 302, 351CJ, 429 CJ) for some reason unknown to me seem to wear on the internal portion of the points cam. (the pivot).

Now I only work on things that pertain to me. I am not a professional restoration shop so it seems obvious that my situations may not be common across the board.

In order to maintain accurate point settings throughout the distributors rotation, the clearance on the distributors drive shaft and the points cam need to be accurate.

IF the play between the shaft is greater then maybe .0005". the settings on the points will be inaccurate.

If the cam is wobbling .0005", the then setting on the points will be wobbling at least .001".

Now here is the point, take the cap off the distributor and push the points cam. If you feel it wobble, then it needs to be dealt with.

I have found the cam worn internally as much as .0050". That means that your point setting is off .0100". With that you will not get anything like an accurate coil firing because the points are going to be grounding all of the time.

Now I know that you posted that you set the dwell, but I don't know the method that you have used so there is still a possibility that you have excessive wear in the cam.

Now if after checking this for wobble, you find that it is there you have to deal with this. If you feel it, it is more then .0010".

Those cams have not been available as service parts for decades from Ford and virtually anyone else in the aftermarket.

The three engines mentioned all use vacuum advance along with the dual points and as such those cams are unique and not the same as in the earlier 289hp, 427's, etc.

There are three variations of them depending on the notches in them for the mechanical advance the specific engine uses. As far as I know, three different advances for three different engine families.

So the choices are two. Replace the cam with one that is not worn, if you can find one,  or repair the one that you have by knurling  and reaming it.

As it turns out the dimension is 5/16" and that is an easy knurler to come up with and the reamers are common as well, in both the standard size of .3125" or +.0001 or +.0002, etc.

It is something that you can easily do yourself with these hand tools. Nothing that NASA needs to do for you?

So if you have noticeable wobble in the cam, and you still won't fire with the dual point Ford distributor, investigate for excessive wear internally in the distributor.

Is this a completely bizarre thing to look for? Absolutely, but to some, the situation is right in front of them and completely invisible.

If you have already checked for this and you have no wobble, ignore this and go back and finish the video game you were playing. Just think of this post as an eccentric old guy substituting posting here for therapy.

I am sometimes concerned with this as well. Prefrontal labotomy keeps coming up in a reoccurring dream and I keep escaping the nurse that wants to stick me with that big hypo that she says will calm me down!

Thank you all so much for the help and advice. Looks like this guy definitely has a lot to do. I just hope I don't need to send her to the hospital..

panteradoug - that was great! Technically, I could have made a mistake during the tune-up since I did indeed have brain surgery last year. Something about removing a mass. They might have taken too much as I don't have much to spare.. :-)

I'll provide updates. (For your comic relief if nothing else.)

William

So, I pulled spark plug 8 and it has some deposits, probably carbon. The dry one is the one I replaced.

Ok, looks like there’s no spark. That’s good news because electrical I can troubleshoot, timing, not so much. Stay tuned ..

I don't know if it's relevant. But, the shop I worked years ago did a tune up on a car, which would not start after the parts were replaced. Turned out the condenser was bad, despite the shop using only brand name parts.

Richard O.

I’ll add that to my list. Thanks opiecars.

...It looks as if the Plug was NOT Grounded during the Testing! That is Exactly HOW You Destroy a Coil!! I Did Warn You!!

With NO Ground, the High Voltage 'Seeks' a Ground with-in the Coil, and Finds it To the Primary Wiring! This 'Burns' a Permanent 'Path' through the Windings that will Forever be a Short in the Coil! The Coil becomes Junk! The HIGH VOLTAGE Has to 'DUMP' somewhere...and it's To the Primary Ground, INSIDE the Coil!!  FWIW

Yup, the  coil is first on my list 👍. Thanks Markin.

Depends who you ask….😁

Thanks Marlin. (I was typing without glasses and missed the l and hit the k accidentally. Like I said, close but not quite all there.. 🤪)

I get good spark off the high tension lead from the coil, so I would say the primary circuit is good? If so, then the problem is in the secondary circuit.

Ok, Marlin was right, not only was the spark plug not grounded, neither was I. I’m (me) definitely not firing on all 8.😩

We do have spark.. 🫤

...Good Spark! Coil Good! Go For IT!! See If the Inside of the Dist. Cap is 'Carboned-Up'.

Oh, wait, the Cap and Rotor is New?

If You need to Re-Gap the Points...I always went with .017". A Great 'Feeler Gage' is the Carboard of a Matchbook Cover. Dual Points May be Different.

How can the plug not be grounded? If it is installed into the head, it grounds to the head?

Granted the plug is a mess but if it is installed and torked it is grounded. More likely it is just fouled beyond being functional?

My earlier video where I held the spark plug in the air waiting for a spark..⚡️

Not grounded.

OK. Sorry. I missed that.

I didn't suspect that since to me makes absolutely no sense at all to do? But I'm not the most abstract of free thinkers.

...But I see what Doug means...the Oil Fouled Plug, has Clearly NOT Been Firing, OR All of that 'Crud' would have Been BLASTED Away! Plugs are 'Self Cleaning' in That Way. The Plug in the Other Photo, that was 'Dry' and Close to the Correct Color, Looked as if It Had Been Firing 'Normally'! 'Anti-Fouling', One Other Good Benefit of a Dual Fire System. Excepting for Double the 'Burn' Wear at the Spark Gap Points.

...The Gentlemen who suggested that the Distributor could be 180 Degrees OFF Timing...are RIGHT ON, Correct!!! To Make absolutely 100% Sure I'm at 'The Top' of the Compression Stroke of the Number 1 Cylinder. I stick My Finger in the Spark Plug hole, while I Remote Crank the Starter. Ignition OFF Ofcourse. And then Confirm, and Align at the Balancer Timing Marks! Then, I Set the Distributor and Plug Wires. The Rotor Turns CCW.   

...One thing more I'd like to point out about Spark Plugs!

1-2 Out Of 100 will NOT Fire. Not Just because they are Fouled, but because they are Broken Inside. Came-on when 'they' started producing the 'Resister' Plug. The Inside Conductor or Resister is just Not conducting.

It would be a Advantage to all of us if we did the 'Spark' Test, as Demonstrated previously, To all sets of Spark Plugs, before Installing them. Making sure they can even Pass through a Spark.

In the 56 Years I have Been 'Hot Rodding' I have discovered Exactly (2) Non-Functioning Plugs!! How many were Not-Knowingly, replaced as In a Tune Up...I'll Never Know! May have been fouled or even intermittent.

The Above Oil-Fouled Plug in the Photo, may Not have been Fouled by the Oil, but Fouled from Not Firing!

Food for thought!

Thank you for alll the spark plug info! I’ll definitely do all the above. I still don’t see how the cap can be put in backwards? Is has a notch and The 1 is on the front (facing the rear if the car) and wires start there and follow the sequence around.

Regardless, I decided to start by removing the carburetor and clean it. I’ve been having backfires so the jets may be getting clogged.

I’ve had the tuning kit since I bought the car but had been afraid to use it… 😬

Here we go!!😁😁

"I still don’t see how the cap can be put in backwards? Is has a notch and The 1 is on the front (facing the rear if the car) and wires start there and follow the sequence"

You are correct that there is a notch for the cap and that the number 1 tower is marked.

However, it takes TWO revolutions of the crankshaft to equal ONE revolution of the distributor shaft. You must rotate the crankshaft to TDC on the COMPRESSION stroke, then install the distributor with the rotor pointing to the number one position (on the cap).

John

Seriously?!? I'm willing to bet this is the issue. I wish I had asked this the first time it was brought up. I must have got lucky the other times I did the tune up.

I'm half tempted to put the carburetor back in just to see. I had removed the bulkhead and cover last weekend to prepare for the worst.

If nothing else, I hope everyone has been getting a kick out of watching me walk around in the dark... :-)

So "technically" if I were to rotate the crankshaft 360 degrees I would be on the right side of the cycle?

"So "technically" if I were to rotate the crankshaft 360 degrees I would be on the right side of the cycle?"

Yes, If the crankshaft wasn't on the compression stroke.

Pull the #1 spark plug and rotate the crankshaft until it is on the compression stroke (you will feel air rushing out of the spark plug hole as the piston approaches TDC).  Rotate the crankshaft just enough to align the timing marks on the balancer with the timing pointer.

Next, look to see where the distributor rotor is pointing.  If it is pointing opposite the #1 tower on the distributor cap, then your distributor was installed 180° out of sync.

John

two-stroke engines fire every revolution, like our old Yamaha dirt bikes. Four stroke engines fire every other revolution.

But was the distributor ever removed? I though just the cap was replaced.

- Sami

Be aware that the timing point on the balancer can be wrong , it's possible the outher balance ring can rotate a little from the inner balancer.

Simon

@transsami posted:

But was the distributor ever removed? I though just the cap was replaced.

- Sami

That’s correct. I only replaced the cap, rotor, points and wires, so not sure why the distributor or the balancer would have changed. It really makes sense that I’m on the wrong cycle.

Also. I believe the reason the car was becoming hard to start was because when I removed the fuel filter, some black debris came out of the inlet. Since the hoses were brand new when I bought the car (18 years ago 🤣) the ethanol, I understand, could wear out old fuel lines.