351 c starting issues

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kcmash

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Fuel in the bowls is visible.   Can't get her to run.

I would post the video but Sansung is not being friendly.

Kcmash

 
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Don C

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By fires, but won't run, do you mean that it seems to want to start when the ignition key is in the start position? But then dies when ignition key is in run?

If so, the starter solenoid ("I" terminal) is providing voltage to the ignition coil, so it will begin to start, but when the ignition switch is in the run position voltage is not being supplied to the ignition coil. Two possibilities, ignition switch needs to be adjusted or the ignition switch is bad.

 

kcmash

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By firing  I mean it roars to life and then goes straight to dead.

Today:

1) Advanced the timing, started it and ran her for about a minute.  then it wanted to die.  (I had been fanning to keep it running, but we were doing good around 1800 to 2000.  Died after about a minute to 90 seconds like she had ran out of gas.

2) Tired restarting, just as I described.  Advanced  timing a little more same story.  Returned timing to original from today and I get the condition I am in.

3) Checked the metering jets.  They appear to be set good at 1.5 turns.

kcmash

 

Don C

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As soon as it dies remove the air cleaner, look down the carburetor and work the throttle lever by hand, see if the accelerator pump is squirting fuel put of the nozzles, if not you likely have a fuel delivery problem.

If it's not a fuel problem that leaves ignition. As soon as it dies remove a spark plug or connect a spark plug checker and check for spark. If you still have the point distributor it could be either the condenser or coil breaking down. Check the point gap, preferably by dwell angle.

 
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What Don said ... I'd also be examining all the vacuum lines for leaks ..is it timed vacuum advance? .... very odd it should try to run then stop just when it begins pulling vacuum.

is there an alarming smell of fuel?

is idle setting tuned off ?

 

digithead

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man that screams fuel problems to me. Do you have gauge to check fuel pump pressure? If not can you just have it pump into a coffee can and check it?

In between those short parts were you pumping it? If so, then it may be bad carb and it was just running off short squirts from accelerator pump?

 

SteveO_71

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By fires, but won't run, do you mean that it seems to want to start when the ignition key is in the start position? But then dies when ignition key is in run?

If so, the starter solenoid ("I" terminal) is providing voltage to the ignition coil, so it will begin to start, but when the ignition switch is in the run position voltage is not being supplied to the ignition coil. Two possibilities, ignition switch needs to be adjusted or the ignition switch is bad.
Is there a factory tach involved?

If yes, in addition to what Don mentions, could the factory tach be bad such that the ignition line is open? Maybe jumper the tach connections together.

 

kcmash

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Great suggestions!  Keep em coming.

1) Yes a factory tach.  When she ran for a minute or 2 yesterday the tach was working great, as was the oil pressure guage.

2) I am thinking fuel problem too.  Just not sure what to check.  Fuel facts:

 A)  I have a clear filter so I can always see the fuel coming in and have clear sight glasses and everything is full.

 B)  I replaced the fuel pump when starting for the first time last year.  She created enough pressure to show me all the leaks when I have them.

 C)  Nope, no prominent fuel smell or black smoke out the exhaust.

3) Accelerator pump?  Works good.  Solid dual stream squirt with every pump.  I should be able to keep her fanned and running if fuel were the culprit.

4) Vacuum advance.  My idiot area!  When I can't get the thing to idle I can't measure or adjust anything.  I bought a refurbed distributor with vacuum advance.  Changed the points to the Pertonix Ignitor III.   Vacuum advance is connected to the metered vacuum on the Holley.

Other info:  I tried starting fluid and pouring gas down the carb on a couple of attempts.  Usually I get a little more run time from gas down the carb,  I am frustrated with how sensitive the timing is on this thing.  If it is not dead on, the thing wont fire.  I have never in all my years had so much trouble getting a carbureted V8 to run.  

For those of you who don't remember, I did get it to run for about a half hour last year to break the cam in.


I can't imagine a catastrophic vacuum leak after that run.  I did change carbs from the initial start as you can see if you compare the videos.

I feel I am missing something simple.

kcmash

 
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I think you may have a problem with the pertronix III, heard it’s pos. What coil are you using with it? If stock coil, that can be a problem. The best pertronix are the I used with a stock coil, or the II with the pertronix coil. Hopefully it’s something as simple as that.

 
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I'm not the expert here for sure, but I had terrible problems with a Pertronix Ignitor III, said my piece many times. They are (or were) badly made mechanically. The top plate on mine was seen to be moving around and likely shorting itself out while on a distributor machine,

During my ignition wows, I did as Don suggested, went back to points, BUT if your resistor wire is bypassed, you'll need to add an appropriate resistor. I forget exactly what I used Ohms wise, but it was like the Chrysler type that I temporarily screwed to the firewall. I also used my stock coil. With the points, the motor ran great, proving the P III was bad. Pertronix replaced it with a P II and coil, and never had a problem since. Other than I rebuilt the distributor to allow only 20 degrees on crank timing. I found on my '71 4V, 16 degrees of initial is just about perfect. It is a matter of trying this and that sometimes.

As for fuel issues, even though you have a clear filter, (hope it's not glass!!) I think you could still have a blockage somewhere. Does your carb have those porous metal type (can't think of the name!) in the inlet passages? They could be partly plugged. Again, relating to my own issues, while my engine did not die, it was running rough, sputtering etc. Finally I changed all my fuel delivery system. It proved to be a combination of rust in the lines, rubber sediment likely from the use of Ethanol fuel before I bought the car. So after that, no more issues.

Bottom line is there is so many thing that affect the running, it comes down to eliminating one after the other, including ones own FRUSTRATION!

Hope you get to the bottom of it soon,

Geoff.

 

kcmash

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Yep,  I went with the pertonix Ignitor III and the Flamethrower coil to go with it.

I had heard so much praise of the Pertonix upgrade, but complaints about the tach not working, so I went with the III for the upgrades so the Tach would work, the rev limiter, etc.  Got the coil so I could make sure I had solid spark and reliability.

Not sure if I have either of those.

Really tough as a I have long work hours, no gearhead neighbors, no help when I work on it, no scheduled window to play around, and I have to unpack everything and push it outside just to try and run the next test.

I'll dig out the points.  Should I go find a stock coil too?

kcmash

 
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Don C

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You would have had to bypass the resistor wire when you installed the Pertronix 3, so if you put the stock coil back on you'll need to reconnect the resistor wire or add a ballast resistor. For testing purposes I would leave the Flamethrower on. You'll be able to run it or drive it some before the points get too pitted. If it turns out to be the Pertronix you can decide what to do then, Pertronix 2, DuraSpark, or?

 

kcmash

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Just to show my stupidity ,  what is the resistor wire?  I simply followed the directions on the box.

In reading the instructions a minute ago they make it sound like a thermal problem or a low voltage problem.  The thermal issue sounds exactly right for the problems I had last year.

Kcmash



 

Don C

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Point ignitions, on 12 volt systems, use a resistor between the ignition switch and coil to reduce the voltage across the points, which reduces point pitting. If points are run with full 12 volts they'll just last a few hundred miles.

The resistor can be either a wire with a resistive conductor or a ballast resistor added onto the coil. Our cars use a resistor wire. Pertronix 3 requires full 12 volts, so the other symptom you mention, low voltage, is likely your problem.

Pertronix also has an add-on relay that provides 12 volts directly from the battery.

 
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Kc, I'm just wondering looking a the picture on the box, does the one  you have come mounted to a two part plate, or does it just attach to the original points plate like the P II? Since my saga, I have not looked at what Pertronix are now selling. I do know that Pertronix have P III's for different manufacturers and they are not mounted to separate plates to replace the original points plate. What I'm getting at is this, do you have the correct P III for the Ford application. I'm wondering if they have redesigned the PIII to fit directly on the old points plate. I'm just guessing here, so perhaps I'll go check for myself to be sure. Or of course, it could just be the packaging not reflecting the enclosed product.

In any case you must run 12V to it for it to work as Don outlines. Plus the air gap needs to be .030". Can you take a picture of the distributor without the cap on.

Geoff.

 

Spike Morelli

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Just as Don C has stated, the Pertronix units are designed to operate on 12 volt input. I have seen many Mustangs with the original Pertronix simply hooked up to the + and - terminals of the coil, and seem to run fine, however, everyone SHOULD buy the relay kit Pertronix offers to run their ignitions on 12 volts. I have the Pertronix II unit and coil on my car with the relay, and it runs great. A while back, I purchased the Pertronix III unit, because it was advertised as the latest and greatest......minutes later after I had just installed it and was up on the freeway feeling it out....it quit dead cold, and I waited for a flatbed truck to bring the Mustang home, where I immeadiately re-installed the old Pertronix II again and it fired right up So, I threw the III unit in the trash can and ordered a new II unit, which has been in the car since....and I drive it every day.

My install was good on that III unit, I don't know why it's such a problematic piece, but I'm not alone on my experience with it.

 

kcmash

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Ok I see that it IS a two plate type with that crappy plastic bushing or bearing between the plate. I'm almost positive the two plates are moving around and could be causing the module to short out. I do see you have the ground strap attached!!

If you do have the full 12 V already to the coil, I would go buy a Pertronix II and reinstall the original points plate. Then send the P III back to Pertronix and tell them what to do with it! It's a shame, because I think electronically it's good, just a mechanical POS.

This is just my opinion, others may or may not agree.

Geoff.

 
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