Motor dies after startup.

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mattmatthew

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I have a slant 6 converted to an electronic distributor with an MSD box and coil, also a super six setup with the 2 barrel carter. I have not run the car for extended periods of time in over 5 years, but last week I was driving it around the neighborhood, and the engine was fine, idle and acceleration was good. A couple days ago when I was test driving it, the motor started to bog down, and wouldn't idle. It would go into a really rough idle, and then die. Now when I just simply start the motor it'll run ok for a few seconds, rough idle, then die.

I did a couple of searches for motor dying after startup and they all seem to point to a failed ballast resistor as the culprit. And I did a little light reading on google and Mopar Muscle claims that if you're running a nonpoints distributor the ballast resistor is simply not necessary.

Your thoughts on the problem?
 
Well with a bad ballast you'll only have spark while cranking so it dies immediately so thats not your issue.

when it dies can you immediatly re-start it and do the same thing?

how did you wire the MSD? where is the big red and small red wire hooked up?

Was the carb sitting with an air cleaner on it and when driving it did it have one on it?

If you start it and jump on the throttle will it stay alive?

start it from under the hood and see of there is fuel dripping out of the booster (thing floating in venturi above the throttle blade
 
when it dies can you immediatly re-start it and do the same thing?
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Yeah, I can start it right back up again and then'll just die again.

how did you wire the MSD? where is the big red and small red wire hooked up?
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One of my friends wired it up about 10 years ago. I was driving it wired up the way it is now for a good 5 years before I ran out of money to run it.

Was the carb sitting with an air cleaner on it and when driving it did it have one on it?
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Yeah I've been running it with an air cleaner. It's brand new.

If you start it and jump on the throttle will it stay alive?
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The throttle will keep it alive a little more but then once the pressure is off the pedal, it'll die again.

start it from under the hood and see of there is fuel dripping out of the booster (thing floating in venturi above the throttle blade
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I'll give this a shot tomorrow. Thanks for the reply.
 
sounds like the carb gunked up from sitting but let us know what you find. Also insure the pump shot is strong just cuz your there
 
Make sure your fuel pump is working 100% and then if not that make sure the center wire is plugged in correctly to your distributor....IF not that, have power in-line to distributor?

Then to check to see if the Carter is gummed up? Possible, (I have to admit, I didn't read every line but....) see if that thing is working and pumping gas as it should be....

NO Vapor lock on the block?
 
805moparkid said:
sounds like the carb gunked up from sitting but let us know what you find. Also insure the pump shot is strong just cuz your there
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Or a fuel filter is plugged up from all the time sitting, and then being driven again.
That would be the very first place I'd look due to the symtoms.
 
sounds like a 40-year-old gastank has stuff up in it. rust, chunks of stuff, parts of the sending unit, maybe some leaves or even dead mice...
 
HA! the solution was simpler than I thought. Rough idle... adjust the idle fuel/air mixture screws. Duh. So far so good but I will let you guys know if the problem crops up later. Thank you so much for your replies.
 
The FIRST thing I always do when I get one of these old cars is inspect the fuel tank. If it even looks suspicious, out it comes. I rinse it out and look closely in it to see if there is any rust and scale. If there is, I chunk it and get a new one. If not, I clean hell out of it. 30-40 years of crap buildup in the tank and nobody ever thinks to clean or replace the tank when they buy an old car and the they wonder why it's runnin like hell.

The tank is the source. If the source is not clean, you will continually have problems. You need to remove and inspect the tank. Until you do that, you're just chasing your tail.
 
RustyRatRod said:
The FIRST thing I always do when I get one of these old cars is inspect the fuel tank. If it even looks suspicious, out it comes. I rinse it out and look closely in it to see if there is any rust and scale. If there is, I chunk it and get a new one. If not, I clean hell out of it. 30-40 years of crap buildup in the tank and nobody ever thinks to clean or replace the tank when they buy an old car and the they wonder why it's runnin like hell.

The tank is the source. If the source is not clean, you will continually have problems. You need to remove and inspect the tank. Until you do that, you're just chasing your tail.
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Goog point Rusty.
I pulled the filler neck and used a flashlight to chk mine since it needed a new seal anyway.
 
Check all your vacuum hoses and cap plugs to make sure you dont have a rotted hose or cap causing a vacuum leak.
 
All yesterday after I adjusted the idle screws on the car, it ran like a top. Took it on some short jaunts around the neighborhood and when I was pretty confident with the motor decided to take it out on the freeway and back for a longer drive.

This morning I fire it up and there's excessive shaking of the motor. It shakes at idle (in park), badly in reverse, and when I'm in drive it has a dull rattling sound when I try to accelerate. I noticed some minor vibration yesterday but it was not like this.

Any thoughts?
 
Since you changed the idle mixture screws and that fixed or masked the source of the problem, it is important to try to figure if the car is now running rich or lean, and under what conditions.

Have you checked the spark plugs for color? (Do you know how to tell rich versus lean on the plug color?) Too bad you did not check plug color after the good drive yesterday.

Is the 'dull rattling sound' like a hollow clatter that is somewhat medium to high pitched in nature? Can you describe it better? And does it get worse the harder you try to accelerate? Is it worse when the moter RPM's are low or high and you try to accelerate?

You should also examine all vaccum hoses coming from either the base of the carb or higher up on the carb body to see if any are leaking.
 
The clatter sound is not high pitched but kinda low. I hear it only at idle (it's the loudest in reverse) and when I try to accelerate it increases in intensity but when I take the foot off the pedal it immediately goes away.

After I finish this oil change and putting in new coolant I'm going to check for vacuum leaks and then I'm going to pull the plugs. (I have a guide to reading the plugs somewhere, if not, I can google it.)

As far as someone else's suggestion to drop the tank, I see where you're coming from. And it's likely my fuel tank is gunked up, but at the moment it's not an option.

I also wonder if maybe some of the plugs are not firing. I'm also going to check my distributor wire to coil and wires to sparkplugs.
 
Assuming the exhaust system is complete, what is the color of the inside of the tailpipe?

The noise almost sounds like an exhaust rattle against the body based on your latest info.
 
Did an oil change, with a new oil filter.

Changed out coolant.

(Wasn't sure if these were related, but they needed to be done, so I did it anyway.)

Also found out that the thermostat was missing. Like, no one ever installed one. So I put one in.

(I forgot to mention that this is not the original motor, but it was one that my friend drove around in for some time. He pulled it to put a 360 in his Dart. I would assume he never had a problem driving it with no thermostat.)

Checked connections from the coil to the distributor to the spark plugs. Checked each spark plug (they looked ok, slight browning at the tip). Put them back in at 30 ft/lb as prescribed by the manual. Checked spark plug connections to the distributor.

Next I checked for vacuum leaks. I replaced old rubber caps that were cracking. I tried to seal up anything that didn't go out to something on the carb. And while the motor was idling I sprayed some carb cleaner around the seams of the carb, where the carb meets the intake, and where the intake meets the motor, to see if there would be a change in rpm. Nothing.

Except, the motor shakes. A lot. And there's the smell of oil, I'm not sure if it's burning oil.

After all that I tried fidgeting with the carb settings to see if I could smooth out the idle in park. I managed to, at one point, but the motor shakes pretty hard when I go into reverse or drive.
 
I attempted to take video from my crappy phone so you could hear what Reverse and Drive sound like. It starts off in Park, Reverse, Neutral, Drive, and then back to Park.

[ame="http://youtu.be/wJJRHk3T5HA"]http://youtu.be/wJJRHk3T5HA[/ame]
 
Check the vacuum advance for the distributor. Leaky hose from carb to dist, bad diaphragm on distributor? Pull hose from carb and use a vacuum pump to see if it holds the cacuum. (or just suck on the carb end of the hose and stick your tongue over the end and see if it holds)
That's just one of the many little things I had to fix before my AZDart ran smoothly.

BC
 
Is the oil smell coming from the exhaust or the engine compartment? Does the engine smooth out if you drive it or stay rough? The audio was distorted; good idea but the phone's vocoder will distort sounds like that.

How old is the gas? You say that the car has not been driven much for 5 years. If the gas, or any significant portion of it, is regular and is over 6 months old, then this is very suspect. Modern gas is VERY prone to do this. (Premium will do this to a lesser degree, so I am told.) It can do damage inside the engine. Even mixing new gas with old gas will not solve this; the varnish is already formed.

Get some gas out of the fuel pump and smell it; if it is good then it will smell like fresh gas at the gas station. If any of it is bad, it will have a distinct acrid smell of what I would describe as 'dog piss' . If you get any hint of that odor, the gas needs to be dumped 100% and the fuel system cleaned form tank to carb. Your carb's passages may be all gummed up now (which would explain why the fiddling with the mixtures screws changed things), and you can read good info in this forum about valves sticking due to varnish from old gas in the intakes, which can bend pushrods. (And it does not do the rings any good either, as it can cause detonation.) All the symptoms you describe can be casued by this. (The 'oil' small may be this too.)
 
nm9stheham said:
Is the oil smell coming from the exhaust or the engine compartment? Does the engine smooth out if you drive it or stay rough? The audio was distorted; good idea but the phone's vocoder will distort sounds like that.
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it's coming from the engine compartment.

the motor doesn't smooth out when driving. i notice a little bit lack of power. the noise / vibration is the worst in reverse and drive. it smooths out in park and neutral.

i will smell check the gas.

a buddy of mine that's a mechanic also suggested checking the distributor for water. it's been raining a ton lately, and the car pretty much sits outside. he said to pull the distributor cap, spray it with some brake cleaner and make sure the contacts are clean. and to check the rotor for water as well. he thinks one or a few cylinders may not be firing.
 
the vibration could be a broken engine mount in reverse? also idle to low?
 
mattmatthew said:
it's coming from the engine compartment.

the motor doesn't smooth out when driving. i notice a little bit lack of power. the noise / vibration is the worst in reverse and drive. it smooths out in park and neutral.

i will smell check the gas.

a buddy of mine that's a mechanic also suggested checking the distributor for water. it's been raining a ton lately, and the car pretty much sits outside. he said to pull the distributor cap, spray it with some brake cleaner and make sure the contacts are clean. and to check the rotor for water as well. he thinks one or a few cylinders may not be firing.
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^^^^^ this is good advice,, especially if you went ploughing thru any deep puddles...
 
mattmatthew said:
it's coming from the engine compartment.

the motor doesn't smooth out when driving. i notice a little bit lack of power. the noise / vibration is the worst in reverse and drive. it smooths out in park and neutral.

i will smell check the gas.

a buddy of mine that's a mechanic also suggested checking the distributor for water. it's been raining a ton lately, and the car pretty much sits outside. he said to pull the distributor cap, spray it with some brake cleaner and make sure the contacts are clean. and to check the rotor for water as well. he thinks one or a few cylinders may not be firing.
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After you spray under distributor cap, clean the underside of the cap throughly with a clean dry rag; don't spray anything under the cap after that. Moisture can combine with carbon dust under the cap to form 'carbon tracks' that can short out the spark or cause crossfiring between cylinders. Never heard of using brake cleaner but seems reasonable as long as you only get it on the cap.

While there, check that sucking a vacuum on the vacuum line to the distributor moves the advance plate. The sensor for the MSD system should move many degrees of rotation around the distributor shaft with the suction.

Edit to add: Once done with the cleaning under the distributor; test how good the spark is. Take on plug wire off of a plug, put a #2 phillps screwdriver in the end of the wire and set the metal blade on the block but not touching. Start the car and see if the spark jumps the gap to the block; with that MSD it ought to jump 1/4" to 1/2" with a good blue spark. If this is good then you can pretty much rule out bad spark.
 
teringer said:
the vibration could be a broken engine mount in reverse? also idle to low?
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the motor mounts are still pretty new. i did check those, as that seems to be the number 1 reason why a motor will shake. i looked at the mounts while the motor was on, and there didn't seem to be much vibration at the mounts.

i cleaned the rotor cap.

so i did the smell test. gas smells like it would at the pump.

also did the spark test. all six plugs have a very strong spark.

i figured, if any of the spark plugs weren't working, then if i pulled the wire, the bad plugs would be the ones that didn't produce a change in the sound. plugs 4 and 5 didn't give me any change in motor sound / vibration. maybe these are bad?

and i shocked myself. heh. i know you're not supposed to do that but i figured it was a quick and easy way to see which cylinders may or may not be firing.

i don't have a vacuum tester (perhaps i should get one) but i pulled the hose at the vacuum advance side to see if it was drawing any air (to make sure i had it hooked up to the right carb inlet). it didn't feel like anything was sucking so i moved the hose onto one that was that wasn't being used for anything.

could it be that i just have two faulty spark plugs? if it's the plugs should i just change all six?
 
4 and 5 could be a head gasket if its never been replaced ,mine was metal in 73 just replaced it last year.
 
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