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SirDan

SirDan

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Location
Long island, New York
Freshly rebuilt 318 bottom end
360 heads stock small valves
torker 340 intake
eddy 600 cfm carb
340 cam
headers to 2 1/2 pipes with X pipe

I had a running motor in the car 8 months ago. Used the same ignition stuff and carb. At first I had no spark but when i replaced my distributor with one of unknown condition it got spark and now we are at this issue where it runs like crap and wont idle.

CURRENTLY, it starts up easily but wont idle. If you hold you foot on the gas it will stay running. revving the engine up there is sometimes some hesitation.

you can crank the car without your foot on the gas and it will start but then die immediately.

It is firing on all 8 cylinders and i believe the initial timing is set to 12 btdc.


I took the top off the eddy carb, looked great inside floats seemed good squirted some carb cleaner through the jets since I was there.

Checked out the reluctor gap on the unknown distributor looked a bit tight gapped it out closer to spec but no changes in the way it runs.

Tried a different rotor in the distributor and no change.

Checked spark with a spark tester at every single wire, then pulled every plug out and bench tested them all were good.

Idle screws on carb make no difference it seems.

Took the fuel line off and cranked the engine. had plenty of fuel coming out.

Doesn't really smell rich, my eyes aren't melting off my face when i run the car.



Starting to think the mopar gods don't like me.:banghead:
 
if the mixture screws are doing anything, i would suspect the idle circuit is dirty , or the carb just needs a thorough gone through. if you have another carb to toss on there , that would be the hot ticket. with the engine off , look down the carb throat and tap the throttle, you should see an immediate shot of fuel out of the squirters.

it sounds like a carb problem to me
 
You need to pick one thread and stay with it. We can't maintain continuity of "what all" you've tried

You say "you believe" the timing is at 12 BTC. "Believe" is a large grey area. You should be able to check timing --with a light--while cranking.

What does your cranking spark look like out of the coil wire?

The carb my be flooding or you may have a vacuum leak. Try looking down the carb---be carful of backfire---and see if you can detect fuel dripping/ pouring out into the throats.

Consider disconnecting the fuel supply and running the car for part of a minute (idle) on what is in the carb bowls to see if it cleans up.

I'd be looking for a vacuum leak

The thing is, you've started several threads, and they all could be related.
 
freshly rebuilt does that mean to keep timing chain and cam shaft were replaced? from what you're describing it sounds like you have retarded cam timing.
 
67Dart273 said:
You need to pick one thread and stay with it. We can't maintain continuity of "what all" you've tried

You say "you believe" the timing is at 12 BTC. "Believe" is a large grey area. You should be able to check timing --with a light--while cranking.

What does your cranking spark look like out of the coil wire?

The carb my be flooding or you may have a vacuum leak. Try looking down the carb---be carful of backfire---and see if you can detect fuel dripping/ pouring out into the throats.

Consider disconnecting the fuel supply and running the car for part of a minute (idle) on what is in the carb bowls to see if it cleans up.

I'd be looking for a vacuum leak

The thing is, you've started several threads, and they all could be related.
Click to expand...

Sorry about all the threads, just trying to keep with the rite sub forum for the subject. Should have started here I guess but, I thought after fixing my spark issue it would all be fine.

I say I believe it is at 12BTDC because it wont idle so its advancing on me. FWIW I just tried playing with the timing and it ran the same no matter where I put it.

The pump shot is working good on this carb.


reshly rebuilt does that mean to keep timing chain and cam shaft were replaced? from what you're describing it sounds like you have retarded cam timing.
Click to expand...

Installed it at factory specs. I was very careful when I put the chain on I really don't think I messed that end up.
 
also I had a vacuum gauge hooked up for a bit. At a guesstimated 1500 rpms I had 10 pounds of vacuum holding nice and steady on the gauge.

not sure if that helps any.
 
big vacuum leak, - put your air cleaner/silencer back on,, then fire it up, and listen real close,, you;ll likely hear it sucking.. . my .02.. cheers
 
Here is a trick for you to get it close on the Initial timing before starting it again.

Find TDC and back up the Balancer to where it is pointing to 20* BTDC "for example" on the timing mark. Hook up your timing light like normal. Turn the key on but DONT crank it. Move the distributor until the timing light flashes. Walah, you are set at 20* BTDC
 
Mad Dart said:
Here is a trick for you to get it close on the Initial timing before starting it again.

Find TDC and back up the Balancer to where it is pointing to 20* BTDC "for example" on the timing mark. Hook up your timing light like normal. Turn the key on but DONT crank it. Move the distributor until the timing light flashes. Walah, you are set at 20* BTDC
Click to expand...

Heyyyyy thats a pretty frickin slick trick!! Hope my memory is good enough to retain that! Thanks

Is the crank/timing gear new?? When we put a new one on dads 273 I buggered it up and put it in the wrong position...good thing we noticed before we put the engine in the car.....there were 3 choices...
 
Mad Dart said:
Here is a trick for you to get it close on the Initial timing before starting it again.

Find TDC and back up the Balancer to where it is pointing to 20* BTDC "for example" on the timing mark. Hook up your timing light like normal. Turn the key on but DONT crank it. Move the distributor until the timing light flashes. Walah, you are set at 20* BTDC
Click to expand...

That's a good trick!

It really needs that much initial timing though?


The timing chain wasn't brand new but I did have it off. I don't remember how I oriented the two dots on it but I know I did my homework and put them the proper way. The timing chain didn't have any other keyway slots on it.
 
Hey Dan, not talking about the dots between the crank and cam gear lining up. What I messed up on dads was that the crank gear had 3 different slots for the keyway on the crankshaft...did you put the crank gear back on in the orig position?? Sorry I sometimes babble and dont get my point across right...just ask Lori....
 
SirDan said:
That's a good trick!

It really needs that much initial timing though?


The timing chain wasn't brand new but I did have it off. I don't remember how I oriented the two dots on it but I know I did my homework and put them the proper way. The timing chain didn't have any other keyway slots on it.
Click to expand...

You want enough Initial timing to where it starts to kick back on the starter, wherever that is. I would start with 20* every motor is a lil different. When I say Kick back what I mean is that it starts dragging the starter down before it fires off, then back it off a couple degrees on the initial timing.
 
4spdragtop said:
Hey Dan, not talking about the dots between the crank and cam gear lining up. What I messed up on dads was that the crank gear had 3 different slots for the keyway on the crankshaft...did you put the crank gear back on in the orig position?? Sorry I sometimes babble and dont get my point across right...just ask Lori....
Click to expand...

Oh, I'm pretty sure it didn't have any other keyways.


You want enough Initial timing to where it starts to kick back on the starter, wherever that is. I would start with 20* every motor is a lil different. When I say Kick back what I mean is that it starts dragging the starter down before it fires off, then back it off a couple degrees on the initial timing.
Click to expand...

Cool Ill give that a shot.



Trying to figure out a good way to check for vacuum leaks. It won't idle so I don't know if usual methods work. Ill try putting the air cleaner on see if I can hear any hissing but my exhaust is pretty loud.
 
Lining up the timing marks on the cam n crank gears is a good starting point, I always roll the crank over 4-6 times to confirm they're in the right place. A lot of throttle, sluggish response, piss poor vacuum and no idle. The others have told you to look for vacuum leaks and confirm timing. Very solid advice. Cap or plug all vacuum ports aside from vac advance. If you don't hear some whistling or sucking when it's running , your gonna wanna pull yer valve covers and make sure all your valves n rockers are functioning.
If all thats in good order, I'd still wanna pop that timing cover and confirm timing chain position. And before I forget make sure you got a strong blue spark coming outta that coil.
 
If you can maintain steady RPM (the lower the better) with the air cleaner on spray carb spray around the base of the carb and where the intake meets the heads, If the R's jump you have a vacuum leak.
 
Ya...pull the #1 plug and get it at TDC. Then notice where the #1 wire is on the cap...pull the dizzy up and move the rotor until u get it pointing at #1. Sounds like u are off a little. R/T
 
Bad ballast resistor.

The thought came to me last night as I lay awake in bed. Usually when ballast resistors fail they just stop working. Mine on the other hand was still working but putting out low voltage to the coil resulting in weak spark causing it to run like crap.

went out there today, jumped out the ballast resister and fired it up. Let it settle down to idle and set the timing at 20 btdc. :thumbup:
 
1wild&crazyguy said:
4 prong ballast by chance?
Good job on figuring it out on ur own, these old cars are really cake when it comes down to it..
Click to expand...

yeah its a 4 prong, I also have a 4 pin orange box. I think I read somewhere it only needs a 2 prong ballast with the 4 pin ecu box?
 
SirDan said:
yeah its a 4 prong, I also have a 4 pin orange box. I think I read somewhere it only needs a 2 prong ballast with the 4 pin ecu box?
Click to expand...
yes

im glad you figured it out
its nice when its something simple
 

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You can run either box as long as its wired for a 5 pin and uses the 4 prong ballast.
The fifth prong simply is not used and gos to nothing if you end up plugging into a 4 pin box.
I used to wire my cars that way just in case the parts store only had one or the other in stock...

But if you hook the wires up wrong on the 4 prong ballast....u can end up sending the low voltage to the coil, and have problems like urs ;)
 
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