Stumped- Can't Figure out Why Car Won't Run...

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Joined
Apr 24, 2013
Messages
860
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Location
SE MI
My Car
1971 J Code Mach 1
1972 H Code Mach 1
I drove my car into my garage in the fall of '21 after getting it running and driving with a new-to-the-car 460/ C-6 combination.

The engine was out of a different car so it had a T-sump road race pan on it, and there was some significant contact with the Hooker headers that was kind of solved with a big hammer.

The plan for the winter of '21-'22 was to pull the engine and replace the pan with a deep front sump pan that would (hopefully) solve my header clearance issues. I finally got things back together this spring but have not been able to get the car running again.

All it wants to do is occasionally fire a plug or two, but it never seems to fire all cylinders consistently or enough to see what the timing is.

I am running a DS1 setup (red box grommet with the appropriate coil that checks ok) and I have tried two different distributors, a different DS1 coil as well as wiring in an old points setup directly from the battery to rule out issues with the electronic setup.

I don't think its fuel delivery related, my Holley street/ strip pump seems to be delivering more than enough fuel (confirmed w/ pressure gauge at the carb and at the shooter(s)) and the carb shouldn't have major problems from sitting for a year (accel pump shot is good etc.).

I have changed the plugs for fresh ones with no effect.

I have pulled the valve covers and plugs and barred the engine over to see if I could spot flattened cam lobes but nothing seemed immediately obvious to the naked eye.

I have re-stabbed the distributor(s) more times than I can remember with no effect.

The only thing left that I have not done is drain the fuel and try it on fresh gas to see if that is the issue.

Does anybody have any other ideas? This has me feeling like an idiot.

I am trying not to think about the cam going flat but that might explain why nothing else seems to make a difference...
 

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I would start with the easy. Recheck your firing order. Make sure you dont have the distributor 180 degrees out. Make sure your timing marks are correct. You can use a piston whistle and piston stop to find true TDC and see if your pointer is pointing to 0.

As far as setting timing without a timing light, you can get it really close before you fire it up. This is also how I set my timing when installing the distributor. Turn the engine over and use the timing marks to get around 5-10 degrees before TDC. The distributor rotor should be pointing pretty close to #1. Pull the #1 plug out and let it ground on the engine somewhere. Now with the key on, you can wiggle the distributor back and forth and watch the plug spark. And thats how you know where to lock the distributor down. It'll get you within a couple degrees of whatever the timing pointer is pointing to. It should definitely be close enough to gut the engine to run.



For fuel, you can test without draining the whole tank. Disconnect the rubber hose at the driver's inner fender. The connect your alternate fuel source there. I have seen guys run the line to a red gas can, and even strap the can to the car and drive around. I have personally run the motor off an old pepsi bottle full of gas. This particular one looks like it was cherry pepsi. The windsor motors like cherry more than the plain stuff.
1687884963549.png
 
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+1 with giantpune, verify timing and firing order before going any further. A good shot of ether in the carb will tell you if it's the gas or not. If you did wipe out some lobes, I would doubt that you wiped out enough to keep the engine from starting. Remember the basic 3 - air ,fuel, spark. Air is a no brainer. Fuel - sounds like you are getting it from what you mentioned, but is the gas good? If gas is good than that leaves spark. Have you tried pulling a plug or two and seeing if you have good spark. A good blue or whitish is best. A yellow or orange spark will not get the job done. With a DS1 the box might be the problem. Don't know it you can actually bypass it. Are you for sue it is wired right. Might want to wait until its dark out to crank it over a couple of times. You might find the coil wire is arching or maybe a crack in the distributor cap. If you have something arching, it will show up in the dark. If no or weak spark than I would start measuring voltage. Good luck.
 
Bad fuel is a possibility. Not sure what you have access to or how old it is but using fresh "real" fuel never hurts. Run a hose to a fresh can of gas before draining the tank though. Good luck.
 
Mjlan,
Did you do anything with your exhaust while the car was sitting ?.
what about mouse/rat nests in the pipes ?.
Also, the DS ignition should have 2 circuits in which the ignition should produce a spark, crank and run, have you verified both with the distritor you intend to use ?.
With all the spark plugs removed, perhaps the engine will crank fast enough to get a glimpse of where your timing is and also clear the cylinders of unburned fuel ? ( recommend cranking with the distributor disconnected in case you have any gushers that could catch fire.
Boilemaster
 
I recommend changing the fuel filter on the carb (if you have one). In addition add a Fram G2 clear gas filter. This will allow you to monitor the sentiment from the bottom of the gas tank and replace the filter as needed.
 
Halon works quite well with electrical fires as well, and as you noticed, no cleanup required. Halon doesn’t extinguish by starving/displacing O2 and lowering surface temps like a CO2 unit. The halon interferes with the free radical reactions occurring at the fuel/flame interface. If the fire is large enough, the decomposing halon can produce HCN (hydrogen cyanide) and some other nasty actors, so post fire ventilation is always a good practice and lessens the odor of grease fire smoke. Great for carburetor fires on engines and won’t hurt a running engine like dry chemical can. Dry chem powder (monammonium phosphate) can be corrosive if sprayed on a hot metal surface or sucked into the engine internals.
More than you probably wanted to know… 🤷🏻‍♂️
 
What is the best place to purchase a Halon fire extinguisher? I know, Google is my friend. ;) Is it ok to keep it in a garage that can go from 45-ish in the dead of winter to 95 in summer? Those would be the extremes, and for most of the year it's not too bad in the garage.
 
Did you ever resolve the issue? When I first read this post, I wondered if the distributor was turning with the engine. The old, oil pump shaft breaks issue. I mean if you have fuel, good coil, and even close timing, it should be backfiring through the carb or exhaust, unless the rotor is not turning. Just a thought.
 
I agree with Roland, check for spark. But,, it is not as easy as it may sound. Case in point, I once had a 1978 Granada 302 come into our dealership. Barely out of warranty, and well maintained as it was a dark green color and belonged to a local businessman. It came in an hook, and I had just done a mqnitenance tune on it a few weeks prior. I checked the fuel pressure and vlume, and the accerator pump was squirting well. The distribut eas turning and looked to be lined up on the #1 cylonfer poer stroke with the timing mark was a 6 degrees (and 180 out on the subsequent rotation). I had the engine hooked up to the scope and I was getting consistent spaark to all cylinders.

After doing all the basic diagnostics I took a fuel smple and made certain it was ignite and burn. Still nothing. Finally, I pur a simple external ignition coil gauge in the coil high volttage output terminal/ It was peaking at only 16 k, almost enough to fir the plugs but not quite, hence the consistent voltaage firing output on the scope. I changed the coil for a new one and the engine roared to life. From that point forward I never trusted a scope to reflect if the plugs are firing or not. I got an old plug, screw driven hose clamps, and a medium size alligator clip. Ever since then I use a plug wire ar the plug end and connect it to the test plug, then clamp the alligator clamp to ground, and turn the engine over. If it sparks I go elsewhere. No spark, I go backward testing for ignition issues.
 
Well, I have finally got this running again.

I had three issues-
1) failing starter that was drawing WAY too much juice,
2) battery with dead cell that would show 12.7V but drop to 9.x when cranking. Maybe killed by the starter. I didn't notice the low voltage during cranking until I happened to glance at my handy timing light that displays voltage. This was causing weak spark. I had spark, but not consistent and strong.
3) timing not advanced enough. I was not able to verify this until I fixed the above two issues because the slow crank speed was not triggering my timing light so I couldn't verify the timing.

So it runs. But I'm contemplating blowing it apart again to swap it over to a 4 speed....
 

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