Moparts

Car stalls when it comes to a stop

Posted By: bigboysurf58

Car stalls when it comes to a stop - 10/13/13 08:53 AM

I need some help with my 69 383 automatic A/C Road Runner. I am having trouble with the car stalling when it comes to a stop when warmed up. I have changed gas tank sender, line, fuel pump, filter, and new Edelbrock 1405, choke deleted because of warm climate. I found that the timming chain had a 10 degree stretch, so I replaced it and at the same time installed an Edelbrock Performer intake and aluminum water pump, recored the radiator. I found that the vaccum advance was inoperable on the points distibutor, so decided on a Pertronix Billet distributor and flame Thrower 3 coil, new wires, 65 amp alternator, an electronic voltage regulator, but run it through the ballast resister, because it runs really bad if I don't. When the car is warming up it runs good, but as it gets warm it starts to stall when slowing down or stopped, amp meter drops negative. when I load it with lights and A/C it gets worse. After it stalls it fires no problem, but starts to stall when I put it in gear. I switched out the Pertronix with a good points ditributor, but same thing. Timming is at 12 btdc at 750rpm. It seems to be elctical but not sure where to start. I know all my grounds are good......hope someone can help shed some light on my problem.....thanks.
Posted By: RapidRobert

Re: Car stalls when it comes to a stop - 10/13/13 09:01 AM

Take out the idle mixture screws & afix one of those thin red straws that come on a WD40 can to a can of Brake Kleen & shoot a 2 second blast into each port. Count the # of turns in to lightly seated so you can easily return the screws to their original position. Might have a vac leak. E10 (ethanol) will make it want to stall when hot
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/13/13 09:16 AM

Thanks for the advice...for sure I don't have a vaccum leak, one of the first things I checked after i changed the intake..and I've done the shoot out of the mixture ports....i will look into the rotor phasing....thanks again
Posted By: RapidRobert

Re: Car stalls when it comes to a stop - 10/13/13 09:28 AM

You're way ahead of me! Holler what it ends up being. Got another coil on hand you could sub in for a quick test? But it kinda sounds like fuel
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/13/13 09:49 AM

I have done the change with a good Accel coil with no differance...but will definitly look into wether the carb is getting enough fuel, though the see through fuel filter is at least 1/2 full while running...thanks.
Posted By: 85_Ram_4speed

Re: Car stalls when it comes to a stop - 10/13/13 01:47 PM

How many turns in does it take to lightly seat the idle mixture screws?

I find Edlebrocks tend to like the idle mixture screws around a 1-1.5 turns out from lightly seated.

And to that, how big is the cam in the engine, because it's possible it may need more RPM than 750 for idleing. 750 RPM at neutral idleing may not be enough for when it goes into drive. Do you know the in gear idle RPM?

Also a super tight converter on a biger cam will really drop the RPM in drive and make it very hard to drive around the idle range---for example a small block with a stock stall 904 converter fighting against a mopar 292 / 509 purpleshaft cam. This an example of one I worked on for someone else. The car was then speced for a 3600 stall converter by a well known company and all the other drivability issues disappeared.
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/13/13 04:18 PM

From what the paperwork says when I bought the car, the engine was rebuilt to stock specifications in 2005, by a shop in california, but when contacted they don't keep records going back that far, but by the way the car ran when I first got it, it is stock, no cams, and such.
As for idle, I have had it up to 900, it will still stall. Idle mixture screws are another matter. right now I have both at about 2 1/2 to 3 turns out for the smoothest idle at about 16 to 17 in. of vaccum.
Posted By: 540DUSTER

Re: Car stalls when it comes to a stop - 10/13/13 04:28 PM

whats your fuel pressure? those edel carbs don't like alot of pressure 6psi is plenty
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/13/13 04:54 PM

I'm running a Carter 6903 which should put me right in the ballpark for fuel pressure for this carb.
Posted By: 85_Ram_4speed

Re: Car stalls when it comes to a stop - 10/15/13 01:49 AM

Anyway you can get a gauge on it to be sure?

I have a friend that races and has many times seen pumps NOT put out what they were supposed too---most were over spec. I have my Eddy's set at 5.5 psi for the moment until I can dial it in better. Sometimes you can go more, sometimes not, always best to be sure.
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/15/13 08:17 AM

I installed a fuel pressure gauge tonight after i got home from work, will evaluate tommorow when i get home, and post reading.
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/16/13 06:11 AM

Fuel pressure when warmed up was 6.5 psi. It was idleing at 750 to 900
slowly jumping between 16.5 and 18in of vaccum, then it would go to 19 in of vacuum at 900 for about 20-25 seconds steady, then go back to varying between 16.5 and 18 in vac. It seems everytime I try to drive it it has a new symtom.
Posted By: 85_Ram_4speed

Re: Car stalls when it comes to a stop - 10/16/13 11:34 AM

You may have a case where when driving, it is calling for fuel and the needle and seat is open, but when you let off, and the needle and seat are most likely trying to close at or near that point, you mayy just have a hair to much pressure do to a spike in the fuel system and forcing fuel past the needle and seat, and then out the venturies thus momentarily flooding the car.

It would be nice if you could at least put a temporary regulator on it to lower the pressure just a little bit. If you had a holley on it, that pressure would be just fine.
Posted By: floridian

Re: Car stalls when it comes to a stop - 10/16/13 12:28 PM

First thing I would do is check the float levels in the carb
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/16/13 04:11 PM

Thanks for the advice, will check the floats and see if I can rgulate the flow.....will post results when done...
Posted By: 85_Ram_4speed

Re: Car stalls when it comes to a stop - 10/16/13 10:02 PM

Quote:

First thing I would do is check the float levels in the carb




Great point!! If I were you, I would pull the floats off, and pull the needle and seats out and make sure they are clean, then reassemble and check float height. I have had recent problems with Eddy carbs related to dirty screens on the needle and seats and float levels that are off out of the box. One of my carbs had the float level set so low that there was barely any fuel getting to that bowl in the carb.
Posted By: floridian

Re: Car stalls when it comes to a stop - 10/16/13 10:14 PM

Quote:

Quote:

First thing I would do is check the float levels in the carb




Great point!! If I were you, I would pull the floats off, and pull the needle and seats out and make sure they are clean, then reassemble and check float height. I have had recent problems with Eddy carbs related to dirty screens on the needle and seats and float levels that are off out of the box. One of my carbs had the float level set so low that there was barely any fuel getting to that bowl in the carb.





I was thinking too high and it floods out as you come to a stop..
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/17/13 07:29 AM

Took the top off the carb, and surprise, one of the floats was hanging lower than the other one...reset the float, cleaned the bowls, took it out for a drive and it runs better, and didn't stall.
The problem now is when going up a faily steep hill the transition from slowspeed to accelerating seems to bog down until more gas is applied, about 1/2 to 3/4 push on the pedal then it picks up.... maybe a spring change on the metering rod I'm thinking....will post results...
Posted By: 85_Ram_4speed

Re: Car stalls when it comes to a stop - 10/17/13 11:37 AM

Quote:

Quote:

Quote:

First thing I would do is check the float levels in the carb




Great point!! If I were you, I would pull the floats off, and pull the needle and seats out and make sure they are clean, then reassemble and check float height. I have had recent problems with Eddy carbs related to dirty screens on the needle and seats and float levels that are off out of the box. One of my carbs had the float level set so low that there was barely any fuel getting to that bowl in the carb.





I was thinking too high and it floods out as you come to a stop..




You are right, I was just giving my example of what I found on my out of the box carbs that I was struggling with for a bit over the spring time.

But also, if it is not letting fuel in because it is too low, then you can get an issue there too. I have two carbs so i think one was covering up part of my issue from the other being off.

To the OP, glad it is better, keep tuning
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/19/13 04:49 AM

Tested the new set up....pink spring for metering rods totally eliminated the hestation problem...yay! but still having the stalling issue...boo! Regulated the fuel to 5psi, no affect, so I'm going to go in and check the floats again. Idleing at 800, with 20 degrees advance, 18 inches of vaccum today. If I back down the advance to say 15 or less the engine wants to not idle and stall. It seems to run ok with no accessories on but if the a/c turns on its definitly going to stall....getting pretty frustated...maybe thinking of going to another carb....
Posted By: RapidRobert

Re: Car stalls when it comes to a stop - 10/19/13 05:38 AM

As far as you can tell it was rebuilt with a stock cam?. I'd think it should idle at less than 800 plus not stall when the initial is backed down to 15. Vac leak maybe? something still ain't right & I'm not sure if it is inside or outside the carb. Any possibility the cam phasing is off
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/19/13 07:56 AM

Motor was rebuilt back in 05. I contacted the shop, but they couldn't help me as they only kept records for 5 years. It sounds stock, nice rumble but no lope, just smooth idle. No aftermarket items except performer intake, and 1405 edelbrock carb, and Pertronix Flamethrower 3. I did change the timming chain (CompCams) as the old chain had stretched, installed straight up. The stalling problem was before the installation of these parts.
Funny thing, when I first got the car it ran fine, a little sluggish, but it didn't stall, but it was running a points dist. with a vac, advance that didn't work. then it went downhill from there. It runs better with the Pertronix, but thats not saying much...checked for vaccum leaks after intake installed, but none found...
Posted By: RapidRobert

Re: Car stalls when it comes to a stop - 10/19/13 02:19 PM

To clarify, at one time it ran OK (but a bit sluggish) then it deteriorated with no part changes? & after the part changes it ran a bit better but still had an issue? Were all of the part changes done at the same time (including the dist) & when it first went bad was it all of a sudden or gradually?
Posted By: Dads426

Re: Car stalls when it comes to a stop - 10/19/13 02:27 PM

Thy Edelbrock carbs are jetted fairly lean. Try going up 1-2 sizes larger on the primary jets and see if the stalling & hesitation go away.
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/19/13 04:52 PM

It was a gradual deterioration. I replaced the carb,after replacing everything from the gas tank to the carb, then distributor,wires, plugs, then timming chain, and intake in that order.I was trying to eliminate problems and change suspect old parts. The Pertronix was put in place of the points distributor, that had a defective vac advance. Timming chain was replaced when I dicovered the timming was jumping back and forth. I decided to change the intake at the same time, since the front end was apart, and take a little weight off the front. I had thought at one time I might have internal issues, possible burnt valves or sticky valves, not sure. It has been about 25 yrs since my last Mopar (681/2 Super Bee) but man this car has me stumped....I like to tinker but this is really driving me crazy because the car is top shape otherwise.....case of the beautiful car that doesn't run well, and hard to get help here cause Hawaii is 90% Chevy muscle which is fine, I traded my 69 427 Vette for this car. I know it will get resolved, thanks to everybody for their advice.

Attached picture 7893058-7-6-13redlineroadrunner001.JPG
Posted By: RapidRobert

Re: Car stalls when it comes to a stop - 10/19/13 06:41 PM

I keep thinking vac leak & most of the time the valley pans seal well & sometimes they dont. I'd take the clusters out & blast the brass tubes with the holes along the length of the tubes etc with brake kleen and also the recess where the clusters sit plus blast the idle mix screw ports on the chance that it is the carb idle circuit. Might block the metering rods up so you are on the power circuit (tho I ain't sure how much the power circuit is working at idle on eddies) and open up the idle mix screws all in an attempt to richen it & compensate for a vac leak if that is indeed the issue & take it out for a spin & see how it acts. We gotta get this before you trade back for the vette
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/20/13 04:55 AM

I'm thinking its not a vaccum leak, because it was stalling with the original manifold on, did a lot of testing to find leaks pretty sure its not that, and i did shoot the clusters the other day when I adjusted the floats,blew out the mixture ports also, but will richen the mixtures to see how it runs.....will work on it tommorow and see what happens...
Posted By: Pacnorthcuda

Re: Car stalls when it comes to a stop - 10/20/13 05:08 AM

Does the car have power brakes?
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/20/13 08:56 AM

No power brakes....A/C, power steering....when the A/C is turned on, thats guarateed the car will stall when slowing down to a stop. Amp gauge goes negative when stalling happens.
Posted By: dezduster

Re: Car stalls when it comes to a stop - 10/20/13 04:38 PM

I am thinking timing,I would check stock harmonic dampener for slipped outer ring. If ok.
I would still add some INITIAL timing up to 15, tune distributor curve for 35 degrees at 3000 rpm, add as much vacuum timing as it will tolerate for cruise. Then start chasing carb issues if any.
In my experiences when carb acts finicky at idle tune distributor for best vacuum, adjust carb for best idle.
One other thought, I have seen multiple edelbrock timing chains installed incorrectly due to vague 0 degree timing marks on lower gear. If you didn't use one of these sets no worries.
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/23/13 07:59 AM

Changed jets today, 104 from 100, same rods, about two steps richer.
let engine warm up, set timming to 13 btdc 750 rpm. Blip throttle a few times to 3000rpm, seemed ok, turn a/c on blip throttle again, as rpms drop goes negative 750rpm, down to almost stalling then comes back up to 750. Blip again, rpms drop to stall. Start up again same procedure, rpms drop, and again almost stall engine, but goes back to 750. As rpms drop close to stalling, amp meter reads negative. Rpm drops to 680-670 in drive and reverse. When a/c is off, tendency of stalling seems to be less, but as car runs longer, tendecy to stall goes up, a/c on or off.
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 10/28/13 08:21 AM

Took the RR out for a run, stopped at a friends house close by, he was thinking maybe the A/C compressor might be causing the stalling, by putting too much drag on the engine....too much pressure or something like that...it stalled again at his house as soon as I turned the a/c on and blipped the throttle...is there some test to check the compressor for drag on the engine or running too much pressure...
Posted By: bigboysurf58

Re: Car stalls when it comes to a stop - 01/09/14 07:53 AM

To all who helped me with suggestions up to October 28, I kept working on the car, and what I finally figured out was that the gas
I was using, 10% ethanol mix, was giving me the stalling problems. I couldn't believe that made all the difference. I did change the carb to a Edel 650 AVS, from a 1405, and I went back to my original points set up, but I have to say the RR purrs now.....so, it was the ethanol fuel blend that made the car run like crap.
Thanks for all the help....
© 2024 Moparts Forums