440 stops when hot. Help wanted.

[clausoe]

Just when I get one thing fixed something else seems to goes wrong. I recently fried 2 coils because it turned out the alternator was pressing out 19 volts. The first coil I thought died of old age so I changed it and it fired right up but then died after 20 minutes of driving. Thats when I discovered the charging problem. I now have a "rice type" mitsubishi internally regulated alternator, a volt guage, another new coil and big smile on my face. With car running I have 14,6 volts at the battery, 14,5 volts to the ballast resistor and 11,5 volts to the coil, an Accel 12V coil.

Now to the problem, when test driving earlyer today the engine starts to stutter on idle and misfires when I touch the gas. It only happens when the engine has become good and hot. Eventually it stopped and would not fire at all. Took of the air filter and could see gas squirt when I turned the throttle arm, and was afraid it was an ignition problem again. Now because I just did all these modifications to the electrical system including new wiring I couldn't imagine this was the problem. Now because I assumed I had a spark and could see there was gas I thought the cylinders must bee too wet, if thats what it's called. I put the gas pedal to the floor and held it there to get enough oxygen and after a while it came to life. Now I have to find out what could be causing this and hope you guys can help me.

Could the spark plugs cause this? They seem fine to look at even though they are a bit old.
The carb is a new edelbrock 800, If it's the carb it seems like its running too rich when hot, but that seems strange since its worked fine until recently.
Could a faulty fuel pump be causing this stuttering and stopping? If so would it misfire when trying to accelerate?

To try to explain it as clearly as possible: When engine is hot it's fine at constant speed, on idle it "seems" to either get to rich or looses its spark and stops. If it doesn't stop it will backfire out of the carb when I try to drive. If it stops it might start with the throttle held wide open while cranking.

I actually cant tell if its getting too much or too little fuel, or if it's a spark problem.

Thanks

Claus

[RECHRGD]

I think your new coil is bad.  Just yesterday my Accel 12v (chrome) coil died after only a year and the car was acting identical to what you describe.  I put my old (yellow) coil back on and was good to go.  The guy at the parts store said that the chrome ones die easily, as they don't disipate heat well.  Just a thought!  Bob

[clausoe]

To be honest that was my first thought because the car died the same way on the last two coils. I just cant believe it has happened again, especially since I have been measuring the voltage everywhere as if I am developing a paranoia about the coil going bad. And guess what...it is a chrome one as well.
But it did eventually start so I am not sure yet.

One things for sure, I'm really really sick of new parts going bad so fast.

[clausoe]

I went out and borrowed a coil I know works and then drove the car until it started to stutter and want to stop, took about 15 minutes. Then I stopped and did a record breaking coil swap to se if it would run any better with this other coil. It did not, so I am now assuming the coil is ok and the problem is elsewhere. But where?

[RECHRGD]

How hot is "good and hot"?

[firefighter3931]

Sounds like vapour lock. How hot is the carb getting ? Can you hear fuel boiling when you shut it down (hot) ? Any of the fuel lines exposed to heat sources ?

Ron

[clausoe]

Vapor lock is a possibility but I then have to wonder why it hasn't been a problem before. There was alot on the vapor subject when I tried to do a search and the symptoms are very similar. There is much talk about a insulating gasket, I have the original edelbrock gasket that followed the carb in the box, will this do? I'm not familiar with the gasket part numbers being mentioned. There was an interesting theory of a bad fuel pump causing low fuel pressure and that causing the fuel to vapor when the engine gets hot. What do you think about that?

Thanks

[firefighter3931]

. There was an interesting theory of a bad fuel pump causing low fuel pressure and that causing the fuel to vapor when the engine gets hot. What do you think about that?

Thanks

Yes, that is possible. A crack in the pickup tube that lets air into the fuel line can also cause aeration of the fuel = vapour lock. A clogged fuel filter, low fuel pressure...you name it. It could be just as simple as a bad tank of fuel. 

How recent is this problem ? Has it all ocurred using the same fuel ?

Ron

[myk]

If you're looking for more ignition gremlins, it could also be your distributor.  I had the same problem you had, and I chased every down every possibility including bad coils, vapor lock and whatnot.  Turns out that my distributor's pickup/reluctor whatever you wanna' call it had gone bad and was randomly malfunctioniong-even more so when the engine was hot...

[dodge freak]

Yes that happens alot with msd dist. ,so I have heared. If its old just change it, does not cost too much and no point in waitting till it just dies and then you have to change it.

[clausoe]

I took a visual control the distributor pickup and it seemed ok and nothing was loose, what could go wrong with it? isn't it just a magnet? Where can I buy just that part?

I had the carb apart earlyer today because someone said it might be remains from the lead substitute stuff I'm using and cleaned it with pressure air. It didn't help either.

[dodge freak]

Its on a plate that has 2 or 3 screws on the side of your dist. Remove those screws and un hook the lead out of the dist.should just lift out, no wait I think the wheel or its called the reulater or some like that comes out first. The part right under the rotor. It has a pin on the side, watch you don't lose it. You can by all that new too for under $10.00 but it only has to be change if it rusty or has alot of nicks on it. The first time you change it might be easier to pull the dist. But then you may mess the timing way up. If you can get all the screws on the side out, then take 2 screwdrivers , 1 on each side and try to lift that little wheel off. The plate comes right out then. Once you get the new one in it has to adjusted with a fleer gauge for around .010-.020 depending on which dist you have. I think mopar its .010 and msd its about .025 . You may want to look it up or take it to a shop and have them change it. They do go bad sometimes and yes sometimes only when its hot. I would change it before you do an thing else.

[clausoe]

I changed the fuel filter today. It is a see through unit so I can se whats going on. I took the car for a drive and it ran perfectly for an unusual long time but then suddenly at an intersection it stuttered and stopped. I crank it and it sounds like it almost will start a few times but no, and then there is no fireing at all. I roll to the side and take a look at the fue filter and it is almost empty. I remove air filter and hear fuel squirt when I press the throttle. I crank without pressing the gas and nothing. I crank with the gas pedal to the floor and it eventually starts again. With the engine running I look at the fuel filter and it looks like it varies from being almost empty to fo fuel occasionally flowing in but it is never over 1/4 full.

Can anyone make sense of this? Isn't the fuel filter supposed to be full of fuel and not vapour?

Oh, and when I drive it home after it starts it seems to run fine but starts to pop out the carb of I give it too much accelerator. Now that wouldn't be an ignition problem would it?

I'm sorry if it might seem I'm posting the same questions over and over but I just can't find anything wrong.

Thanks

[TylerCharger69]

My coil once gave me the same grief.....getting to hot and expiring....so....I mounted it on the passenger side firewall...no troubles since!!!

[Headrope]

Any a-hole kids made at you? What you are describing sounds exactly like something I went through when some kids put BBs in my fuel tank. It runs fine for a while, until the bbs get sucked up against the fuel pickup and blocks the flow. WHAMMO - no gas ... engine sputters out which cuts the vacuum on the pickup allowing the bbs to drop. Start the car, make it a block and WHAMMO - vacuum sucks the bbs up again. It's a real pain in the ass.
I replaced most everything fuel delivery wise. Never thought to check the tank.
If no reason to expect a-hole kids I'd guess your coil is getting too hot.

[RECHRGD]

Strong possibility of some garbage in the tank clogging the sock on the pick-up.  Maybe just an old and plugged-up sock.   Bob

[dodge freak]

I am glad I have a locking gas cap on my car, forgot about that. Put one on 10 years ago for that resone. Those kids with their "rice burners" or what ever you want to call their piece of junk cars are sometimes pretty sore losers. Don't trust the grown ups too, when they call the cops on you and find out they won't [ can't ] do anything to you , they sometimes act like kids. Not to say thats is your problem and maybe you just have a bad fuel pump or a vapor problem. If you have a holley you can carry a small amount of gas in a glass bottle and a very small funnel and pour some gas down the vent tube to the sight hole and see if it runs good for 15-20 seconds. Never try it on a eddy or carter carb so it might not work for you.