318 Won't Start? And I tested as much as I could I think?

-
Just askin cause I been there, did you put those plug wires on in the correct rotation? First fire on my 360 a couple years ago, I fought with it for a couple days before I realized I had put the wires on the cap in a counterclockwise rotation instead of clockwise which is what a small block wants.

Cley
 
nm9stheham said:
The ICM is not field testable without special test equipment. Substitution is what is done. I'd try to find and OEM one off of eBay.. what you get from overseas these days is questionable.

The point of the teaspoon full of fuel down the throat is that the IF the ignition is good, then it will fire off with that, even cold. Since it did not fire off, then I am pretty suspicious that something is still amiss with the ignition. 1/4 cup? Wow, that is a TON; it shouldn't have taken that much.

Do you have a volt-ohmeter so other parameters in the ignition can be tested? Things like the actual ballast and coil resistance need to be checked to be sure you have the right parts. If so, and you are willing to run down some checks, then I can list some things to measure.

You mention fuel out of the jets; do you mean the small circular 'things' down inside the carb's throats? (Those are called auxiliary or booster venturi's... see the 1st illustration here:
Automotive Systems)

At idle, there should be NO fuel visible out of these at all. Your needle valve in the float bowl may be stuck open with dirt/crud and just flooding things.. or the float level may be way off for some reason. Doing the carb rebuild is on track to clear up things like that.

Sounds like you may be plagued with 2 problems at the same time...carb + ignition. It happens.... not to mention the ball joints on the DD!
Click to expand...

Okay, I've been away from the issue for a bit.
I am definitely making progress though, with the choke coil unhooked I can get it to fire up for a couple seconds from a cold engine though it takes 5 peddle pumps. And on it's own that's all it will do. With the choke hooked up there was nothing. After a few couple second starts I can throttle it up to keep it going. So as of this afternoon this is my current test readouts.

-Coil Voltage: Odd – pos showed 3.6V and neg showed 9.4v
-Coil Resistance: 1.7

-Ballast Resistor Resistance
Off, Upper: 2.0 Lower: 5.5
On, Upper: Lower:

-Spark Plug Gap .035 and Test
Cylinder 1: Hot Blue at 3/8’’ gap
Cylinder 2: Hot Blue at 3/8’’ gap
Cylinder 3: Hot Blue at 3/8’’ gap
Cylinder 4: Hot Blue at 3/8’’ gap
Cylinder 5: Hot Blue at 3/8’’ gap
Cylinder 6: Hot Blue at 3/8’’ gap
Cylinder 7: Hot Blue at 3/8’’ gap
Cylinder 8: Hot Blue at 3/8’’ gap

-Compression Test PSI (They all seem a bit high and uneven bank to bank)
Cylinder 1: 127.5psi holding
Cylinder 2: 132psi holding
Cylinder 3: 127.5psi holding
Cylinder 4: 132psi holding
Cylinder 5: 127.5psi holding
Cylinder 6: 130psi holding
Cylinder 7: 127.5psi holding
Cylinder 8: 130psi holding

I was going to try and get it warmed up enough to stay running on it's own and get a good timing reading, It sounds a little better today even though I did nothing to the timing or cap.
The numbers in the electrical system seem off on everything?
I'm going to test it again tonight with another tester I just had to get a battery for.
And it seems odd that the passenger side bank seems a bit higher in the compression?

Thank you and everyone helping so far, I will lay out a symptom specific test and repair breakdown when this is finished.
 
- Coil resistance sounds close. Make sure you measure it + to -with all wires disconnected.
- Coil voltages sound suspicious.....
  • makes sure a brown wire goes to + and a black or black-yellow wire goes to -
  • turn the key to run without starting and measure the + and - voltages
  • if - is still higher than +, then something is probably wrong in the wiring to from the key to the ballast and coil +
- Ballast sounds like it is upside down....needs some checking. Remove all of the wires to it and recheck resistances. The post with the single brown wire coming off of it should be the on half that has the much lower resistance. 5 ohms is normal for one half; 2 ohms is a bit high for the other but may be tolerable for now.
- Spark sound good (which is a GOOD sign but not consistent with all of the above data).
- And compression numbers are VERY good and consistent. Being a bit different one side the the other is not of any huge consequence; small head, deck, or head gasket variations will make those 5 psi differences. Were these numbers taken with a bit of oil added into the cylinders or 'dry'?
- Sounds like the idle circuit is not doing ANYTHING. Try restarting with the 5 pumps, and when it fires, keep pumping it rapidly and see if it will stay going.
- What is the room temperature there?
 
What is the synopsis on this? Should not take 3 pages and whatever time this has been to get a SB Mopar fired up
 
IMHO, there is some learning going on.... which is fine, and which is how we all started waaaay back when LOL.
 
nm9stheham said:
- Coil resistance sounds close. Make sure you measure it + to -with all wires disconnected.
- Coil voltages sound suspicious.....
  • makes sure a brown wire goes to + and a black or black-yellow wire goes to -
  • turn the key to run without starting and measure the + and - voltages
  • if - is still higher than +, then something is probably wrong in the wiring to from the key to the ballast and coil +
- Ballast sounds like it is upside down....needs some checking. Remove all of the wires to it and recheck resistances. The post with the single brown wire coming off of it should be the on half that has the much lower resistance. 5 ohms is normal for one half; 2 ohms is a bit high for the other but may be tolerable for now.
- Spark sound good (which is a GOOD sign but not consistent with all of the above data).
- And compression numbers are VERY good and consistent. Being a bit different one side the the other is not of any huge consequence; small head, deck, or head gasket variations will make those 5 psi differences. Were these numbers taken with a bit of oil added into the cylinders or 'dry'?
- Sounds like the idle circuit is not doing ANYTHING. Try restarting with the 5 pumps, and when it fires, keep pumping it rapidly and see if it will stay going.
- What is the room temperature there?
Click to expand...
 
As for the 3 pages, the majority of it is all multiple responses for the same questions. I don't want to seem to new because I'm not, just truly lost after doing what I new was right.(At least based on general concept of spark, air, fuel, and compression). Also I do have the 72 Imperial Service Manual so I did have info to test when this all first started, which I did post and had to repost a couple times to clarify.
I defiantly did not plan on this taking this much time to work out. Especially when the extreme lack of fuel seems like the main issue. Or at least to get it to flash for a second.(even though starting fluid was used) It is really frustrating on my end, and truly thanks again for all the help in keeping me sane.

Well I was measuring the coil voltage from the terminals to a block ground and not across the coil terminals. So I assume that the issue there, but for some reason I also think the pos and neg wires may be backwards as was mentioned.
But if these turn out to be backwards and the coil were to have proper voltage. Why would it have been able to run?
I'm going back down for a bit later I think so I will take some pics of the area and a video if I am able to post it. And then post it and an update after I recheck the other stuff later.
Also, as I said I am able to get it started now. It just takes a bit and requires constant throttle playing to keep it going though. It is in park and it sounds potentially strong, just in dire need of a real good tune up.
Another thing I found out was there should be a plastic spacer between the carb and the manifold, is there? There is only currently an extra thick gasket around 3/16", Is this necessary on a small 2 bbl or is the thick gasket good enough?. I know they improve atomization and air flow on larger carbs and manifolds.
I really think it's an overall Carb issue at this point.
 
I was mostly looking for an update LOL. The coil doesn't matter for polarity in this situation. They will "eat plugs" if run for long periods backwards, and don't make as strong as spark "so to speak." so far as starting and running, should not really matter

"Measurements" yes, measure from coil terminal to ground

With key "in run" not running, coil NEG should be quite low perhaps 1/2--1 volt. This is because the transistor in the ECU is conducting and holding the coil NEG "close to ground"

The POS terminal varies depending on the coil and resistor, should be anywhere 6-8 or maybe 10V

"Cranking" the coil POS should be "same as battery and at least 10-10.5V
 
Well it turned out that the coil was reversed, rechecked and readjusted everything last night but I was limited do to the weather. Just went down there today and gave it 2 light pumps and it fired up but wouldn't run. So I unhooked the choke again with no go and then it took about 5 pumps to get it to flash but I was able to keep it going with the peddle. Basically 1 try with the choke and 1 try without, then the 3rd try it flashed up And I could keep it going. It would stay going on it's own so I adjusted the idle screw enough to keep going. It started to smooth out a bunch as it warmed up and I was able to set the timing to 7.5 advanced at 800rpm. Once it warmed up it flashed up and stayed running with little trouble. And this is a couple of the pics I could get that weren't blurred 1 of the carb it the choke and the other shows the front of the bowl is wet
20180618_200131.jpg
20180618_204156.jpg
20180618_204211.jpg
20180618_204211.jpg
20180618_204233.jpg
20180619_153914.jpg
20180617_151557.jpg
20180617_151626.jpg


I am pretty sure I am down to just carb issues.
I was going to take a video of it flashing up and running but I'm not sure if I can upload video's in a post?

Never the less....
I have reached the point where I am able to get it started and running once warm, and this is where I was trying to reach with these problems.
If it wasn't for the help from everybody and their suggestions I may still be frustrating myself.
Unfortunately I now have additional questions and problems in the carb so I was planning on starting another thread if I cant' find what I need somewhere.
Either way let me know what you guys think.
 
I see the carb. Autoline rebuilds arent what they used to be 20 some odd years ago.
I put one on my power wagon,wouldnt run. Demanded my old carb back and rebuilt it myself. To this day its still running.
 
Tooljunkie said:
I see the carb. Autoline rebuilds arent what they used to be 20 some odd years ago.
I put one on my power wagon,wouldnt run. Demanded my old carb back and rebuilt it myself. To this day its still running.
Click to expand...

Thanks
It's good to know to be sure not get another one ever. I was intending to get a rebuild kit and rebuilding it but now I think I will just rebuild the old original carb instead, provided it's not just too far worn.
Also, does anyone know of a thread for 2bbl carter differences between auto and manual transmission carburetors?
 
67Dart273 said:
What is the synopsis on this? Should not take 3 pages and whatever time this has been to get a SB Mopar fired up
Click to expand...
So is this O.K.?..... Just Kidding:) I'm just putting this in to wrap up and say thanks


Well as I said I would try and recap at the end so here it goes.


I had been starting up every month to get it hot and fully lubed. Toward the winter this sort of stopped and then 4 months later I tried to take to a car club and it ran like crap. As if it was misfiring combined with down cylinders, really rough. So I tried starting it again and the same thing had occurred (sounds like misfiring combined with down cylinders, really rough). First thought was the octane had gotten low in the gas, so I added some to no avail. The next few times of trying to start it were over a few days and it seem to worsen until finally it wouldn't fire up not even for a second or two.


From there I went back to basics, gas, air and fire... the carb is shooting clean streams out of the top so that should have been at least enough to fire for a second or two. Also tried starting fluid with no success.
So with a wide open throttle and a bit of fuel from the carb if should fire with spark?


From there changed plugs, plug wires, coil, rotor cap, rotor, and ballast resister.

All with no change, as well as tried other ECM’s. I also checked all parts of the timing, along with compression and spark.

So, this is when I asked for help…….. And it was very helpful in different ways of testing and checking.

Thank you again everyone! :)

On top of what had tried there were great thing to test.

  • Reluctor and pick-up gap

  • Setting timing by the reluctor

  • Testing for a stronger spark 3/8’’ – ½’’ gap with a hot blue spark

  • Different ways to determine TDC

  • Testing the coil strength - check voltage to coil + when cranking; it should be 10-11 volts. That will check to see if your coil bypass for startup is working. If it is not, then the voltage will be lower, in the 6-9 volt range

  • How to test the ballast - Pull the connections off and measure resistance on the 2 halves; one half should be around 5 ohms and the other < 1 ohm

  • Preferred timing – different then the book(better though) - you want AT LEAST 5-10 BTC on a dead bone stocker, and more if you have a "mild cam" in the thing.

  • Setting Plug wire locations

  • Cam Timming – ensure it hasent slipped or there is no damage

  • Ensuring there it new fresh gas

  • Checking Compression

  • Choke and wide open throttle setting – proper choke at start up no full throttle, Choke is for regular start up, full throttle is only for a flooded engine.

  • Why not to use starting fluid – Excessive starting fluid washes oil out of the cylinder and piston rings requiring oil to be added through the spark plug hole to be safe.

  • How to spot water in fuel

I agree with most people in the fact it may have been a coincidental two issue problem, Ignition and Carb. I say this based on the fact, initially when I couldn’t get it before changing or adjusting anything I tried starting fluid. This should have at least kicked it for a second since it is so explosive, but no. After checking everything I could think of in the manner I knew there was no progress.

I then tried everything in the list as suggested, and then with a lot of extra fuel I was able to get it to flash up. And then More adjustment to be sure timing was correct. And that brought me to where I am now, not entirely witch item was the problem or if it was merely a matter of cleaning and resetting the ignition system properly.

All of this is easy to test and the parts purchased were something that should be replaced in a tune up anyway.

And now it’s time t move on to 2bbl tune up, repair, or replace?


Thanks Again

Chad a.k.a VolksDuster

73' Plymouth Duster.JPG
 
Yes, the coil won't make as good a spark when reversed, as said. Simple.... but not what you would expect. Just part of the issues. I bet it will run better all around, and now you have done a lot of testing to get a good baseline for the future. If you read enough threads, you'll notice that the guys who have done this for a while can recite things like cranking compression on this engine or that from memory.

Good synopsis!
 
73' Plymouth Duster.JPG


Are those Scoops original to that car. If I remember correctly those where available on a duster only for one year.

I have a pair of those on a 69 Cuda Hood sitting on my breezeway.

By the way love the color that's a good looking car.
 
Jadaharabi said:
View attachment 1715189919

Are those Scoops original to that car. If I remember correctly those where available on a duster only for one year.

I have a pair of those on a 69 Cuda Hood sitting on my breezeway.

By the way love the color that's a good looking car.
Click to expand...

Thanks for liking the look, me to that's why I am trying to get it going asap to drive it again. It's hard not having the mechanic (my grandfather is not able to help or direct not to repairs or rebuilds) DAMM Strokes. But he does watch sometimes and wants to for a drive again.
He is the one who found it actually. It's hard the see but that's not a tornado duster on the rear sides of the car, it's actually lettering that spells out (TWISTER). I haven't seen another (Mopar Blue Duster Twister) like that as well, but as for the hood I am pretty sure I've seen them on a few years. But I also could be crazy thinking of something else.
Check out this link, just as a reference. I have never purchased from there.

Duster/Valiant Parts - Roof & Hoods

So Yup. the scoops are original but cosmetic only, they are just for show :(, they were only available on the twister model for 73'. It is all original car, accept for Air breather, valve covers, dual exhaust and wheels. We were the second owners that got it from and old man who only drove it one day a week.
The hood had to be repainted due to the extreme paint brush touch ups that he did, there are also some small ones still in the blue on different places of the body.
Pictures never do a car justice, they make an okay car look great and a great car look okay.... There are a few rust spots that need to be fixed as soon as its running real well again and I can afford it.
 
Last edited:
You must log in or register to reply here.
-

Back
Top