What is it, guys?

What is it, guys? - 05/04/13 08:26 PM

), the idle, and the air/fuel mixture screws, etc.....
It runs good for a bit, then it seems like if it gets warm it does the same [Edited by Moparts - Family Friendly Site - Keep it clean], will hardly idle, backfires, won't pull under a load, etc.....
I don't have a lot of time to go work on it during the weekends, but there are some things I wanted to try.....I took the adapter it had on it(didn't need it), since it was leaking a little around the baseplate. Still does it though. the car has a factory electronic ignition from the 70's installed on it, Im oredering an orange box mopar kit this weekend, and some accel wires, and coil.

Like I said, I haeven't had a lot of time to check everything I want to. I guess it could be a vacuum leak still, the carb, or the ignition,. Maybe it's the fuel pump, I dunno. Oh it's a 70 swinger 340 btw.....if that helps.

somebody that knows a little more help me out please, lol. My field of knowledgeis in welding and fabrication, Im not a virtuoso with a tourque wrench, lol..... It probably something very simple, I almost feel stupid for asking, but I have always been told the only stupid question is the one not asked....thanks in advance guys!

Posted By: stumpy

Re: What is it, guys? - 05/04/13 08:44 PM

Orange box is trouble. You"d do better with a stock box.

Posted By: Hailtheleaf538

Re: What is it, guys? - 05/04/13 11:35 PM

Quote:

Orange box is trouble. You"d do better with a stock box.

What's the problem with them? I know my dad had one his 72 340 Beeper....we never had any issues with the box or distributor,however did have some problems with the voltage regulator.....always use to carry a spare one, lolmaybe it was related to the orange ecu.... I wasn't aware of any issues with the orange box, but I'll check into it.

But anywho, Im wondering if anybody has an idea on what is most likely the cause of the problem

.....Thanks again in advance for any advice, guys.

Posted By: SattyNoCar

Re: What is it, guys? - 05/05/13 01:48 AM

If I remember correctly, if the orange box was made within the last 15 yrs or so, its suspect. The older ones could go 100's of thousands of miles before problems arose.

Posted By: Hailtheleaf538

Re: What is it, guys? - 05/05/13 01:58 AM

Quote:

If I remember correctly, if the orange box was made within the last 15 yrs or so, its suspect. The older ones could go 100's of thousands of miles before problems arose.

Wow, really? I hadn't heard that one before...glad you guys brought it up. The one on the runner was back in '94 or so.....when I was in Middle School.

How about any suggestions on the fix for the car, though?

Posted By: ohiodemon

Re: What is it, guys? - 05/05/13 02:03 AM

have you tried a different carb ?

Posted By: SattyNoCar

Re: What is it, guys? - 05/05/13 02:27 AM

Ok, my Dart runs and idles great in the morning (ive deriven it to work a couple of times since I got it), but when I come out at the end of the day to drive home, iot won't idle , spits, sputters, backfires, etc, etc....I've tinkered with the carb(an edelbrock ), the idle, and the air/fuel mixture screws, etc.....
It runs good for a bit, then it seems like if it gets warm it does the same [Edited by Moparts - Family Friendly Site - Keep it clean], will hardly idle, backfires, won't pull under a load, etc.....

My

Today's gas will boil and vaporize if held too close to a hot cup of coffee. To me it sounds like you're getting vapor lock. It doesn't have to be 100 degrees out for it to happen, I've had it happen with temps as low as 50.

A weak fuel pump may compound the matter. Check your fuel pressure both hot and cold. Today's gas is also harder on rubber parts and may have damaged the diaphragm of your pump.

I'd also try to insulate any metal lines underhood.

In extreme cases, some people have swapping in a fuel/vapor separator type of fuel filter (I did with my wagon) and run the vapor line back to the tank.

Posted By: Hailtheleaf538

Re: What is it, guys? - 05/05/13 04:53 PM

Quote:

have you tried a different carb ?

No I haven't had a chance to yet, but I do have a Weber 750(been stored at dads since the mid 90's) that I was going to put on and see what happens. Isn't it the same exact thing as a Carter AFB? I mean it looks exactly like one anyways.

Posted By: Mr.Yuck

Re: What is it, guys? - 05/05/13 05:01 PM

The orange box thing is a myth because I've never had one go bad...lol re-ground it. as for what 73Sat said, yes get the carb off the hot intake. you should have at least a 1/2" spacer. see if that helps. If the ecm was bad it'd be dropping fire all the time.

only other thing I can think of is you have a junked up fuel filter or maybe fuel sock???

Posted By: Hailtheleaf538

Re: What is it, guys? - 05/05/13 05:04 PM

Quote:

Ok, my Dart runs and idles great in the morning (ive deriven it to work a couple of times since I got it), but when I come out at the end of the day to drive home, iot won't idle , spits, sputters, backfires, etc, etc....I've tinkered with the carb(an edelbrock ), the idle, and the air/fuel mixture screws, etc.....
It runs good for a bit, then it seems like if it gets warm it does the same [Edited by Moparts - Family Friendly Site - Keep it clean], will hardly idle, backfires, won't pull under a load, etc.....

My

Today's gas will boil and vaporize if held too close to a hot cup of coffee. To me it sounds like you're getting vapor lock. It doesn't have to be 100 degrees out for it to happen, I've had it happen with temps as low as 50.

A weak fuel pump may compound the matter. Check your fuel pressure both hot and cold. Today's gas is also harder on rubber parts and may have damaged the diaphragm of your pump.

I'd also try to insulate any metal lines underhood.

In extreme cases, some people have swapping in a fuel/vapor separator type of fuel filter (I did with my wagon) and run the vapor line back to the tank.

Thanks for the response, your

is worth a lot more than that to me. I thought I would post what I thought it might be, and then see what people who actually knew what they were talking about thought.....

Posted By: JohnRR

Re: What is it, guys? - 05/05/13 05:05 PM

Quote:

Quote:

have you tried a different carb ?

No I haven't had a chance to yet, but I do have a Weber 750(been stored at dads since the mid 90's) that I was going to put on and see what happens. Isn't it the same exact thing as a Carter AFB? I mean it looks exactly like one anyways.

Yes it is as is the edlebrock you have on it now. What size is the current edlebrock carb on the engine , is it a performer series or thunder ?

Throw a rebuild kit in that carb before trying it , the accel pump is probably dried out so you'll have a problem there.

What type of choke is on the carb ? If it's electric is it adjusted properly?

Posted By: SattyNoCar

Re: What is it, guys? - 05/05/13 05:08 PM

If the ecm was bad it'd be dropping fire all the time. only other thing I can think of is you have a junked up fuel filter or maybe fuel sock???

When my old orange box went bad, it would cut out no rhyme or reason. It would go days with no issues, then cut out multiple times in a day.

The way I understand it, the new orange boxes aren't as 'tough' (for lack of better word). A poor ground, a voltage spike, the thing is toast in one hit. The older ones could take this kind of abuse for awhile before crapping out.

The fuel filter and sock is good to check, but, wouldn't cause a problem just when warm.

Posted By: Hailtheleaf538

Re: What is it, guys? - 05/05/13 05:15 PM

Quote:

Quote:

Quote:

have you tried a different carb ?

No I haven't had a chance to yet, but I do have a Weber 750(been stored at dads since the mid 90's) that I was going to put on and see what happens. Isn't it the same exact thing as a Carter AFB? I mean it looks exactly like one anyways.

Yes it is as is the edlebrock you have on it now. What size is the current edlebrock carb on the engine , is it a performer series or thunder ?

Throw a rebuild kit in that carb before trying it , the accel pump is probably dried out so you'll have a problem there.

What type of choke is on the carb ? If it's electric is it adjusted properly?

the choke on the edelbrock isn't hooked up......the Carter is an electric chioke, and the edelbrock is a 600cfm from the 90's on a perfomer intake. Would just as soon have a holley on it, but I don't want to buy a bunch of little quick fixes that are going to be useless to me in a short time. Hope to get the suspension, trans, squared away, then have the motor built up quite a bit hotter.

Lol ihope to purchase a home within the next month or two as well, so Im kinda holding off on doing all that work until I move......

I almost wish I had $40,000 laying around to send somebody along with the car and tell them I want it back in a few months.....

Posted By: JohnRR

Re: What is it, guys? - 05/05/13 05:23 PM

Quote:

the choke on the edelbrock isn't hooked up......

And you wonder why it runs the way it does .

Is it manual or electric ? If manual is it just flapping in the breeze or wired open ?

Posted By: Hailtheleaf538

Re: What is it, guys? - 05/05/13 05:25 PM

Quote:

Quote:

the choke on the edelbrock isn't hooked up......

And you wonder why it runs the way it does .

Is it manual or electric ? If manual is it just flapping in the breeze or wired open ?

Um.....it stays open. Wile Im not an expert, I'm not mildly retarded, but thinks for the jab anywyas.

Posted By: RO23dave

Re: What is it, guys? - 05/11/13 01:05 AM

Sometimes the floats can get porous and then they sink to the bottom of the bowl. when you take your carb apart, a bad float will have fuel inside of it. causes all kinds of hell. just one more thing to check out. Dave ss/ea #1355