Hard to start when cold

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dano said:
It should be hooked up to ported vacuum. Some use full vacuum but that is for far more built engines.
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dano said:
Assuming stock distributor, is the vacuum advance hooked up? Is it to ported or full vacuum? If its on Full vacuum (i.e. the port has vacuum at idle) move it to the ported (i.e. no vacuum at idle) Reason being is the vacuum advance at idle might be giving you too much advance and that's why you need to retard it and why it runs crappy if advanced.
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I do think you may be on to something do you happen to have a picture of what ported advanced looks like?
 
dano said:
It should be hooked up to ported vacuum. Some use full vacuum but that is for far more built engines.
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Based on this picture without being at home I can tell you ours is hooked up to the center and the left nipple

IMG_0138.png
 
AJ/FormS said:
Get your idle-tune worked out first, and then the cold-running on the choke will be a whole bunch easier.
Before you start:
If you have installed a Single-plain intake with a large plenum, swap it out for a hi-velocity DUAL-plain. You can make the engine idle on that hi-rpm intake, with a good tune; but that tune will only be good for idling.
Make sure the gas is fresh, and pours out clear as water.
Make sure the secondaries are closed up tight but not sticking.
Make absolutely sure that ALL the air that the engine is getting, is coming in past the throttles and, from the PCV.
During the tuning, if you have powerbrakes, pinch off the booster supply-line. Later, after the tune is in, make sure it runs exactly the same after the booster is back on line, especially as the pedal is applied.
Make certain the VA is on the sparkport, and that the unit works.
if you have a 1406 AFB style carb, they are tuned pretty lean, yur very likely gonna have to get a strip-kit.
If you have moved the A-pump rod between the three holes, you may have lifted it too high; the fuel MUST exit the nozzles, immediately upon throttle-opening.
Do not set the WET fuel-level too low, as the engine will struggle to get the transfers to wake up

Ok this is a good time to mention;
Your engine has several timing requirements. In order of importance they are;
Power-timing at WOT
Timing at stall-rpm
Part-throttle Timing with the VA doing it's thing
Cruise-timing with the VA maxed out
Idle-timing, with the T-slot synced to the Idle screws.
You CANNOT optimize the Idle timing and still drive the beast without detonation, with the factory systems, so don't even try. AT BEST, with a single-pattern timing curve, the idle-timing will have to be, whatever you get after connecting the markers of Power timing and stall-timing. If you need a different Idle-timing from the fall-out, the you will need a kink in your timing curve, which will require two different from eachother, springs. Therefore, where I'm gonna take you, is gonna make your Idle-Timing as perfect as it can ever be, with the parts that you have; BUT, subsequent changes will muck with it, and you may not get perfection back, without modifying the distributor parts.

Ok, to get you started,
Yank the carb off, flip it upside down, make sure the choke is NOT on any fast-idle step. Then;
set the transfer slot exposure under the primary throttle-blades to no less than square. Both of them equal. Probably a little taller than square will be better, then set the mixture screws to 2.5 turns out. After this, DO NOT RESET THE SPEED SCREW.
If it was me, at this point I would verify the Float level is correct. Then;
Warm the engine up. Put the engine up on the fast idle cam, at or near 1800, then twiddle the mixture screws for smoothest rpm. If your mixture screws have to be more than 1/2 turn from 2.5 out, or the engine runs rough no matter where you set them and the secondaries are known to be closed; then the engine is struggling with the transfers. Get that sorted with needles, jets, or IABs. When it likes 2.5, drop the idle back off the fast idle cam, but do not muck with the previously set speed screw. To change the idle-speed, reset the Idle-timing....... by ear, to say 700 on the tach, in N/P.. say 600 in gear. When this is done, verify that the engine still likes 2.5 turns out, at idle.

After you have this slow-speed system dialed-in, check your hi-rpm Timing, without the VA, say around 3600rpm. Keep it to below 35 degrees, maybe a little less, but DO NOT change the idle-timing! from the previously dialed in Idle-tune. This may require modifying the Distributor guts. Until that is done, it may not be safe to open the secondaries.
After this is done, NOW you can tune the choke. But before you do, have a quick peak at the VA. find out how much vacuum it takes to get her started . Then, when on the choke, keep your eye on what the the VA is/or is not doing, as regards to a stable timing. You can't tune the choke if the timing is jumping around.
The combination of fast-idle after the kick-down, and the Choke Pull-off adjustment, will be critical, but the on-choke timing has to be stable.
As for how much choke-timing she gets, the more the better but, don't go crazy looking for more; she'll run on anything that she is, by now, getting.
The electric part of the choke should rotate the choke to "OFF" by about the three minute mark; depending on how close the idle tune is. This is adjustable by rotating the outer housing to change the preload. You only get one shot at this, during every warm-up.
Ok that gets you the Idle-tune, and a safe 35* of Power-timing.
Generally,
your idle-timing will fall into the window of 5 to 15 degrees. This will depend on how the rest of your timings work out, and how perfect you want things to be. Idle timing almost always gets the chit end of the stick, that's just the way it goes.
Oh, I almost forgot
You're batter needs to be top notch and your starter needs to get up to at least 300 rpm. The Dakota mini-starter can do this,
That ancient reduction-gear starter can too, but it sucks the battery down pretty hard.
Click to expand...
Our Carb is the 1411 model
 
Mikes68charger said:
Here are some pictures we moved the hose over to the right side? Sorry again I’m not as well versed

View attachment 1716410801

View attachment 1716410802

View attachment 1716410803

View attachment 1716410804

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View attachment 1716410806
Click to expand...
Looking at your pics, you have the vacuum line hooked to full manifold vacuum, move it over to the line to the left(looking at the front of the carb) of the pcv hose and plug off the line you just took it off of. Like @dano said, you should be on ported vacuum, not full manifold.
 
70SwingerGuy said:
Looking at your pics, you have the vacuum line hooked to full manifold vacuum, move it over to the line to the left(looking at the front of the carb) of the pcv hose and plug off the line you just took it off of. Like @dano said, you should be on ported vacuum, not full manifold.
Click to expand...
It was on the left side I moved it over to the right side should I move it back to the left side?
 
70SwingerGuy said:
Looking at your pics, you have the vacuum line hooked to full manifold vacuum, move it over to the line to the left(looking at the front of the carb) of the pcv hose and plug off the line you just took it off of. Like @dano said, you should be on ported vacuum, not full manifold.
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The instructions on this carb does say that the left port is for emission controlled cars however this car isnt emission controlled.
 
Mikes68charger said:
It was on the left side I moved it over to the right side should I move it back to the left side?
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I would move it back yes. Dont worry about what the instructions say about emissions, you want it on ported vacuum, go back and read post #26. Then I would get your hands on a timing light and vacuum gauge and post some actual numbers of what your motor is doing. There are members here far more knowledgeable than me who can help you more seeing some actual numbers.
 
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70SwingerGuy said:
I would move it back yes. Dont worry about what the instructions say about emissions, you want it on ported vacuum, go back and read post #26. Then I would get your hands on a timing light and vacuum gauge and post some actual numbers of what your motor is doing. There are members here far more knowledgeable than me who can help you more seeing some actual numbers.
Click to expand...
So we origanlly had it set to the left port and had it set to 5 degrees BTDC and it ran like crap.
 
One more thing to double check. I don't remember reading it in the thread. Make sure your plug wires are on the right spark plug. It's very easy to switch the 5 and 7 (ask me how I know!). I'm sure you know, but just in case firing order is 18436572.
 
66fyssh said:
One more thing to double check. I don't remember reading it in the thread. Make sure your plug wires are on the right spark plug. It's very easy to switch the 5 and 7 (ask me how I know!). I'm sure you know, but just in case firing order is 18436572.
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Yep firing order is right what’s the problem with keeping it on the manifold advance?
 
Mikes68charger said:
Yep firing order is right what’s the problem with keeping it on the manifold advance?
Click to expand...

Do you have access to a vacuum gauge? By knowing how much vacuum your engine is making, we can better advise.

A low vacuum engine, maybe 10ish will benefit from full manifold vacuum at idle. But, once the throttle is open, manifold and timed vacuum become equal to a point.

I've tried both on my car that is making 15 vacuum.. I find it more difficult to tune with full vacuum.

Disclosure, I'm a rookie compared to many around here!!
 
66fyssh said:
Do you have access to a vacuum gauge? By knowing how much vacuum your engine is making, we can better advise.

A low vacuum engine, maybe 10ish will benefit from full manifold vacuum at idle. But, once the throttle is open, manifold and timed vacuum become equal to a point.

I've tried both on my car that is making 15 vacuum.. I find it more difficult to tune with full vacuum.

Disclosure, I'm a rookie compared to many around here!!
Click to expand...
I currently do not have one but I am defiantly going to be getting one.
 
Mikes68charger said:
So we origanlly had it set to the left port and had it set to 5 degrees BTDC and it ran like crap.
Click to expand...

It should run fine on 10-12 Degrees BTDC, I think the comment on the timing chain and/or balancer slipped might be coming into play here. When you run a timing light, does the reading stay steady or dance around? If it dances around a lot the chain could be toast. I 2nd vacuum gauge to see whats up.

How did the car start and idle with the 2bbl and what all did you change? It looks like you have electronic ignition.
 
dano said:
It should run fine on 10-12 Degrees BTDC, I think the comment on the timing chain and/or balancer slipped might be coming into play here. When you run a timing light, does the reading stay steady or dance around? If it dances around a lot the chain could be toast. I 2nd vacuum gauge to see whats up.

How did the car start and idle with the 2bbl and what all did you change? It looks like you have electronic ignition.
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Car does not have electronic ignition we just replaced the timing chain because it was sloppy and just put a new one on with new sprockets these were done to specifications. What's the difference with running it at Manifold Vacuum?
 
Mikes68charger said:
Car does not have electronic ignition we just replaced the timing chain because it was sloppy and just put a new one on with new sprockets these were done to specifications. What's the difference with running it at Manifold Vacuum?
Click to expand...
Full vacuum will advance your timing at idle to whatever the canister is set too. I.e. if you static is 5* BTDC and the vacuum pod is set to add 20* you now have an idle timing of 25* BTDC. You can watch this on your timing gun. Stock balancer it would probably go off the charts.

On the timing chain, did you just "dot to dot" or degree the crank and cam? Did the chain have advance or retard key ways?
 
dano said:
Full vacuum will advance your timing at idle to whatever the canister is set too. I.e. if you static is 5* BTDC and the vacuum pod is set to add 20* you now have an idle timing of 25* BTDC. You can watch this on your timing gun. Stock balancer it would probably go off the charts.

On the timing chain, did you just "dot to dot" or degree the crank and cam? Did the chain have advance or retard key ways?
Click to expand...
We just did "dot to dot" This engine is and was bone stock the only major change has been the intake from a 2bbl to a 4bbl
 
I stopped reading when I read timing by ear.

No human can time an engine by ear. Impossible.

Buy a timing light and learn how to use it.
 
Mikes68charger said:
We just did "dot to dot" This engine is and was bone stock the only major change has been the intake from a 2bbl to a 4bbl
Click to expand...
And it started and ran fine prior to the change? Just eliminating and narrowing down what could.

So when you did the chain are you 100% sure the #1 piston was at TDC and the balancer pointer was pointing to "0"?
 

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