I give up! We will set Grannies old 78 Volare with 54k, on fire this saturday night, on some deserted back road! How many gallons of gas to do the job real good?

I have done everything I can think of. Still bucks and hesitates while driving. Could an intermmitant bad voltage regulator cause this?

Changed the head, set the valves, rebuilt the carb, new plugs and wires, NOS dizzy, new cap and rotor, new coil, new gas and filter, vacuum checked. Has good spark. Ideals good. even disconnected vacuum advance. Solution to ideas not solving problem, a big bon fire of the volare.

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Pet dog, loyal pal. Kick dog, get bit!

Take a deep breath. Put a known good carburetor on the car. Do nothing else. Test.

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Joshua

Ditto. Take a breath and walk away for a bit.

Do a compression check, double check the valve lash- .010 intake .020 exhaust, don't forget the valves reverse position after #3.

What is the reluctor gap on the NOS distributor? Are you sure the coil is good?

I would double check the timing is dead on, make sure the rotor is not 180 degrees off.

The symptoms you describe remind me of situations I have had that were either (a) a bad coil or (b) a bad distributor drive gear.

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Casually looking for a Clifford hyperpak intake for cheap.

You might try a new ECU.

Coil replaced, reluctor set to .006 on pickup coil in NOS dizzy. Carb rebuilt to specs, valve lash on rebuilt head to specs .010 intake .020 exhaust, and yes they reverse after cyl#3. Timing dead on 12' BTDC. NEW ECU installed! The dizzy gear looks fine. If dizzy rotor was 180' out of phase the car would not run... :tsk: right? Car runs, but bucks and hesitates. Have walked away time and again. Been to 3 professional mechanics, one an old school automotive instructor.
$100.00 reward for anyone who finds the gremlin messing with Grannies Volare! Has to be something that causes this bucking. Maybe a stick of dynamite will work! When this is resolved I will post the finding!

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Pet dog, loyal pal. Kick dog, get bit!

Not true. I once had a couple friends who owned a 76 Volare. I had bought the Volare out of a junkyard and fixed it up for them. They decided to give it a tune up including a new cap and rotor and somehow managed to put the spark plug wires in the new cap in the right order but to install the cap 180 degrees off from where it should have been. The car still ran nice and smooth, but they complained that it "lacked power on the highway." They drove it like that for a week before they ran out of gas and abandoned it on the side of the road. I towed it back to my place for them to have a look at it and found the problem. They ended up just selling it to me for a couple hundred bucks.

Installing the distributor cap 180 degrees off is the same as plunking the rotor in 180 degrees off. You car can run, but it will run badly. I would verify that the rotor is under the #1 spark tower when #1 is at the top of the compression stroke. Either pull the #1 plug and turn the motor till you feel air coming out the hole and then stop turning when the timing mark is at TDC, or pul the valve cover and rotate the motor until you see the intake valve open and close and then keep rotating until the timing marks is at TDC. The rotor should be pointed under spark tower #1 on the cap.

Another thought, with the mileage on the car that low, you might have crud built up in the fuel tank blocking the fuel pickup sock. Have you tried blowing compressed air back through the gas line and listening for healthy bubbles in the tank?

Is the EGR valve disconnected and the hose going to it plugged?

What is your curb idle vacuum reading? Vacuum while driving?

Why was the head changed? Is the new head known to be in good shape?

Is the exhaust in good shape? No dents or kinks, no internally clogged muffler or catalytic converter?

Does the bucking and hesitation ever stop? Does it backfire through the tailpipe or carb?

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Casually looking for a Clifford hyperpak intake for cheap.

Have you changed the ballast resistor? I assume it's not lean burn by the description you previously gave so it should have one. The ballast will cause all kinds of goofy problems before it fails all the way and quits running. It's not even worth testing. Just put a new one on and if it doesn't help, put the old one in the glove box. Also, make sure the ground strap that goes from the back of the head to the firewall is attached. Otherwise it will cause voltage problems in the ignition and alternator. Speaking of alternators, pull the field wire off to shut off the alternator. It could have a bad diode that will cause a voltage spike in the system. Also check the carb. and make sure the metering rods are moving up and down freely with the piston they attach to. It is very easy for them to jam even when rebuilt by a professional. Depending on the model carb you have(1bbl or 2bbl), they may or may not be easy to check. The last thing to try would be the Catalytic converter. They were notorious for plugging up. Just loosen up the exhaust pipe at the manifold and let it leak. It the problem goes away then you've found the problem.

Hope this helps.

Joel

Did you check the fuel tank and the fuel pump?

Olaf.

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Aspenized

If it starts and stays running--no matter how badly--when the key is released from "START" to "RUN; the problem is NOT the BALLAST RESISTOR... guaranteed! yes they do cause their share of headaches but get blamed for too many problems that they have nothing to do with;
I would look into clogged sock in the fuel tank, a pinhole in a section of rubber hose along the way, etc.
I have had similar problems with a Diplomat and a 5th Avenue; both were solved with replacing teh sock in the tank.
If IL were closer to ND I would take the car off your hands and even "if" I only parted it, (I havent seen it but a 54K original mile car would have to be quite badly rotted out for me not to run it and drive it) I'd save it from what you have in mind; blow up a Toyota or a Honduh or a Hyundai;

Do it. You'll feel better.

1 gallon spread around should do fine.

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<img src="http://farm4.static.flickr.com/3173/2992308402_5481afb26e_t.jpg">

Remind us. Which carbutetor do you have? Possible mixture troubles. Pump shot, jet(s), air bleeds, choke and so forth.

Did you check to see if the reluctor gap is equal as you rotate the distrubutor? Saw a bent distributor shaft this year. Caused all kinds of grief. NOS will generally be OK, but one never knows if a kid in the stock room dropped it.

Fresh stack gasket? (Manifold)

With the cap off, rotate the engine by hand, then rotate the engine the other direction while watching the rotor. How far do you have to turn the engine in the other direction? There should be little or no slop. If there is, the timing set will need R&R.

Double check that the distributor is installed right on. Being off a tooth can result in problems like this. Coupled with a loose timing set amplifies troubles.

Easiest to diagnose with hands on. Lot's of things can lead to this sort of behavior.

Hope that helps. Burning cars smell bad.

CJ

Edit: Changed the head? What was that about?

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Part of Tyrde-Browne Racing

I bought one that had a wobble so slight it could only be found with a gap gauge. That was enough for it to misfire. Like he said, you don't know what happened to it between the factory and your hands.

And yes, they will run with the distributor a good ways off. Recheck your timing.

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If it was easy, everybody would be doing it.

Yes it is very possible that you have fixed one problem, nut then caused another because of bad parts.


Three east steps to finding the problem, 1 run a compression test, plus a leak down test. ANy old school machanic worth his salt could do this pretty fast. 2 Then put the engine on one of those old school Sun machine scoops and test the ignition and engine condition (power balance test).

3 if nothing found above fix the fuel problem, what ever that may be.


OK, a little more detail on this bucking and hesitation could help. It sounds like your car has one of the old Lean Burn systems ( I didnt read all the post so forgive me if I missed something). Right off they can be bad about being to lean and cause such problems as your having. Something to look for is vacuum leaks around the intake and carb itself. Even a PCV valve that is sucking to much can cause the system to be to lean.

If the bucking and hesitation is right when you first give the car throttle/gas its very possible the accelerator pump is not working right, or the system is to lean. If its to lean this could be because of vacuum leaks, or even the carb needing jetted up. Sometimes they are so close to lean that even our gas we have today can get you leaned out to much.

I also forgot that engine might have a EGR valve. It can be leaking and cause the engine to go lean. Try unhooking the vacuum line to it and plug it. Then take a hammer and very lightly tap the EGR valve to help it close up if its stuck open ( Very lightly now you can bend it, but sometimes thats what they need, bent a little).


Now, does the engine ever smooth out and take gas right ? Can you kick it wide open at any point and get the engine to whinned out in RPM without missing? If so this is a good sign. If not then chances are that you have either a fuel delivery problem ( fuel pump, bad fuel line, gas tank stopped up). ( Check rubber hose that hooks metal gas line to fuel take back under the car, they are bad for closing shut, or sucking air). Or even a exhaust clogged up problem ( Cat convertor stopped up possibley, or even a heat riser closed off tight).


What ever the problem you need to find some more info to help pinpoint it. More detail info on exactly how it acts might help. Something else to give a quick look is to see and make sure the coil is not wired up backwords. And even though you rebuilt the carb what about the possibility of someone putting sugar in the gas tank, or even rust build up, or even a charcoal canistor coming apart inside and all the charcoal plugging the carb back up after the rebuild.

Sometimes it can be little things that get you.


Jess

I am sure you have heard this before..... You need to step back forget you did any thing to this car and start over on your diagnostics! Just because you put new parts on dos not mean there any good (new means it is new it does not mean they are any good) Check compression, check spark, check spark plugs, wiring, cap, verify timing, check distributor, check voltage to ignition system, check for proper grounds, verify valve lash, check fuel pump for pressure and volume, check carburation (make sure carb is assembled correctly with all check balls and jets installed correctly), check for vacuum leaks (intake and carb gaskets, pcv, lines) find a known good carburator and switch. Verify your parts new, used, or nos (new means new not mean good).

sorry for the long post

good luck Cliff N

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This is my hooptie, there are many like it but this one is mine. With out my hooptie I am walking and without me my hooptie is broken down.
1980 dodge d150, sl6, 4sp od, air