Hi. Happy easter....now, I have just installed a vintage air system.....finished wiring today, filled with coolant, hit the switch........turns...but no start! I have checked all wiring, Pulled a plug and cranked....have spark...getting fuel.... ran great the day I started the install....my question may be dumb..but. I cannot think of anything else...im a bolt on guy, not an engine guy, so....I know that I turned the crank a bit while installing the belt on the compressor....is it possible that this changed timing and is the reason it wont start?

Signed, flummoxed in WV.

 

Three things an engine needs to start are air, fuel, and spark at the right time. Look over the area that you performed the mods in.

 

Didn't by chance hit the distributor cap with anything while you where doing the install? A cracked distributor cap could cause this issue.

 

If you hit the throttle linkage a few times, it could be flooded - was that plug wet??

 

no....actually the plug was very dry.......

 

ok....checked again....spark is yellow. I have checked all wiring, etc from my ac install. I have a pertronix ignition system and flame thrower coil. Suppose the coil may have went bad? seems like a heck of a coincidence....but I am lost. Cleaned rotor button, etc.........

 

Seems your spark is weak, do you have a full 12v to your pertronix? Do you think maybe a loose connection?

 

I have checked connections, splices, etc.......lost. sigh.

 

Yes, but is your Pertronix unit connected to a ful 12V, or is it connected to the resistance wire?

Have you tried hotwiring it directly to the battery?

Did you disturb the distributor at all? Any chance you interfered with the Pertronix ground to the distributor body?

- Eric

 

Sorry...I suck at electronics....dont even know what a resistance wire is! It is hooked up as it was when I installed approx 7 years ago. I did not mess with distributor at all until today when it wont start....checked rotor button, etc....put back.

and no.... have not hot wired....what would be the safe way to do that without hosing anything else up in the process?

 

What does the wire to the Pertronix unit look like?
Is it a sort of cloth-like braided material, or is it rubber (plastic)?
Follow it along ans see whether it goes right into the harness, or whether it follows along separately for a while.

Post pictures if you can.

- Eric

 

The wire he would be looking for is connected to the coil. Now the caveat here is that when he is cranking he should have 12v feeding from the "I" terninal on the starter.

 

Make sure every accessory is shut off before cranking
With the starter cranking and using significant amps the electronic ignition can sometimes starve a little- not sure why but i have seen this happen. No problem once the car is running because the starter is not using amps. Also check that your battery has full charge.

 

You're right, OldCutlass. I should have been clearer.

Pertronix wire to (+) coil terminal (a different Pertronix wire goes to the (-) terminal), thence to car's wiring, which would be cloth-covered if nichrome (resistance) and plastic-covered if later copper replacement.

If we're geting to the point of measuring voltage (I was just thinking of having him take a look first), then the voltage will be 12-13V from the (+) coil terminal to ground with the engine running if it's a non-resistance wire, but only about 8V if it's the resistance wire.
BOTH types of wire will give 12-13V with the ignition switch ON and the engine NOT running.

- Eric

 

I would just suggest leave everything connected, but run a jumper to the pos coil post directly from the battery and eliminate all the other possibilities. He can still use the ignition switch to crank it over. If it starts its the wire from, or the solenoid output at the starter.

 

Am going out on 12 hour midnights, so time on car will be limited for a few days.....did however try what oldcutlass said about jumping from + on coil to battery.....same thing. cranks but no start. Even though button looked good....thinking about a new rotor button and cap? its been about 6 years.....thoughts? Still seems like a big coincidence to happen while working on, but stranger things have happened I suppose..........I really am ignorant of checking amps, voltage, etc.....sigh. Curse that yellow spark!

 

No more guesses. You have to start testing things to provide more information.
There is a wide range of possible problems which we here on the interwebs can't possibly hope to divine without knowing more.

- Eric

 

Reseat your coil wire at the coil and the cap. It seems you are getting your trigger, but is it at the correct time can you hook up a timing light to your #1 and point towards your timing mark to see where it is firing. Something may have gotten disturbed during your mod? Bad coil, old worn cap or rotor, bad coil wire, etc...

 

Embarrassed to tell...but found the problem. Ground wire from pertronix to coil was crimped in a hose clamp. Replaced, and it started right up. All the info you gents posted got me to think outside my box, so I thank you, but sorry to have wasted your time.

 

As I like to say: It's always something simple.

Glad you found it!

- Eric

 

So the wire from your coil- to the dist was crimped where? Was it something that you did when you installed the A/C? Just for future reference.

Glad you found it.

 

It was barely inside the heater hose clamp on the hose to intake manifold....I couldnt see....but finally felt around by hand. Yes.....I replaced it during AC install.