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Drossman76

Super Chief won't start

Question

Hello all, 

I need some help please, my '57 Super Chief is giving me some trouble.  It's got a 347 with a 4 barrel Carter AFB carburetor.  It hasn't ran for several years, I was able to get to fire if I poured gas directly into the carb so I tought I'd do a full tune up on it, rebuild the carb and be able to fire it right up.... but now i can't even get it to fire.   I changed the plugs, wires, distributor cap and rotor, coil and rebuilt the carb.  I also changed the fuel pump.  The original pump had the vacuum top part for the treadle brakes but the new one didn't.   Since I'm planning on doing a 4 wheel disk brake conversion with a different style booster/master cylinder I figured I didn't need the vacuum portion any way.  

I put everything together and had my son turn the key and could see fuel being pumped through the filter and into the jets but nothing.  Well, I did find that the carb is still leaking gas out of the butterfly rods so I'm probably going to have to replace the carb.   

I pulled a spark plug and ground it against the engine and I am getting a spark but it looked a little weak.   The engine doesn't crank terribly fast but I'm not sure if that's normal for these cars.  Oh, and the choke tube was broken off in the manifold and I couldn't get the piece out so I routed the vacuum hose to the carb.

Does anyone have any ideas what may be the culprit?  Any help would be greatly appreciated! 

Thank you!

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Sounds like the plug wires may be wrong, Did you assume that the #1 terminal on the distributor cap was the terminal closest to and facing the #1 plug.
It actually starts at the back of the Dist. I found this out the hard way.

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39 minutes ago, JoePentium said:

Sounds like the plug wires may be wrong, Did you assume that the #1 terminal on the distributor cap was the terminal closest to and facing the #1 plug.
It actually starts at the back of the Dist. I found this out the hard way.

Also don't forget that Pontiac distributors rotate counter clockwise, not clockwise, like Chevys. So set the engine at top dead center (TDC) and then set your firing order on your distributor.

Firing Order for a 347   - 1 8 4 3 6 5 7 2

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2 hours ago, Frosty said:

Also don't forget that Pontiac distributors rotate counter clockwise, not clockwise, like Chevys. So set the engine at top dead center (TDC) and then set your firing order on your distributor.

Firing Order for a 347   - 1 8 4 3 6 5 7 2

Thank you!

With what you both said, the diagram I used as a reference was definitely incorrect.  I'll go out and plug the wires into the correct distributor location and give it another try and advise of my success (or failure) lol

 

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Well I definitely had the wires wrong, i installed them correctly but still no firing.  I'm beginning to wonder if I didn't perhaps mess something up when I "rebuilt" the carburetor yesterday.  When I took the #1 spark plug out to check for TDC it wasn't wet with fuel and it should have been since I had been cranking it for several attempts beforehand.  I have a line on a used Edlebrock 750CFM carb that I'm going to pick up tonight.  I know it's way more fuel delivery than the engine needs, but at this point I just need to get it running.

 

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Have you checked your fuel pump to make sure it is pumping fuel? Or is it electric at this point? Diaphragms go bad on the old mechanical pumps, especially if they've been sitting for a long time.  Just one more piece of the puzzle you might want to check. Did you check the fuel filter in the carb, is it clogged?

Also, you didn't mention it the last time, were you getting spark when you were trying to turn it over, after you re-did the wiring?

Good luck, you are getting there.

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I didn't get an opportunity to check for spark after I rewired the distributor since I was by myself, but I know I need to do I can at least check that box off. The fuel pump was replaced and it is moving fuel so I know that part is working.  I can't even get it to try to fire, I tried finding a diagram or picture to confirm exactly which port corresponds to the #1 cylinder to make sure I do have things in the right order but i wasn't able to find anything clearly defining, like the #1 plug is "x" ports clockwise away from the rear cap screw or something similar.  

In regards to the two auxiliary wires on the ignition coil, does the positive or negative wire go to the distributor?

Thank you

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Can either of you tell me which one of these diagrams shows the correct #1 distributor location?

Screenshot_20180905-192010_Chrome.jpg

Screenshot_20180905-191956_Chrome.jpg

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Update: I moved the distributor wires one port counterclockwise to match the diagram that showed the #1 port in the very back, I'm now getting puffs back thru the carb, no firing yet, but this is at least some signs of life!

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Look at your rotor turning with the cap off, that verifies dist. rotation, next look at the rotor tip as sometimes they get twisted to the side and will not line up with the plug wire terminal.

Knew a guy with a 69 Z-28 that tore down the engine to the timing chain and was ready to pull it when I noticed the tip was facing sideways on the rotor.

With a new rotor and 45 minutes later she fired right up.

Now the question is how old is the timing chain and is it loose?, has it jumped timing? Has the dist. ever been pulled? if it was, was is it aligned right when it was reinstalled?

I don't know how many times I have seen distributors reinstalled 180 out.

To determine these and other gremlin issues:

1. Pull the valve cover on the drivers side

2. Pull the cap off of the distributor

3. Slowly bump the engine and watch for direction of rotation of the rotor

4. Verify your wire order and that it follows the rotation of the rotor and engine firing order

5. If all is ok so far we go to the trickier part where you might need two sets of eyes 

6. While someone is bumping the engine watch the valve that is inline with the intake manifold runner going to number 1 cylinder and wait for it open and then close

7. Now your timing mark on the harmonic balancer should be coming up on top dead center. The timing marks area should be aligning with the notch on the harmonic balancer and the rotor should be pointing to the number 1 plug wire terminal on the cap or really close to it.

8. This will let you know if the distributor and timing chain are synched and if it did jump time it will still be close enough to start.

9. If the rotor and timing mark on the balancer are where they should be you will be (barring an electrical, mechanical,  or fuel delivery issue) close enough to start and be able to adjust the timing, a vacuum gauge plugged into a intake vacuum port would help a lot also.

Edited by JoePentium
mis-numbering of instructions

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I drained the fuel out of the fuel tank today and added known fresh gas, installed an Edlebrock carb and reverified the distributor wires are correct by getting the #1 cylinder to TDC and verifying that the rotor was pointing at the #1 distributor port. When we tried to start it I could only get the popping back thru the carb but it wouldn't even try to fire. I can't find any marks on the crank pulley to see if the timing is correct, I'm going to try to clean the pulley really well tomorrow in the daylight. I'm wondering if the timing is advanced or retarded too much?  I know that backfiring thru the carb is a lean fuel issue but I found it too coincidental that both the old Carter AFB and the Edlebrock are set too lean.  

I'm definitely stumped....

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I'm back... I replaced the points today and have them adjusted to 19 thousandths. I was able to get the timing set to 6 degrees BTDC which is from what I can find, where it should be.  I'm getting much more popping thru the carb (even had it shoot a little fire out of the carb) but it isn't even trying to fire.  I don't know what else to do at this point, I've had older vehicles all my life and have never been able to get them to run, heck, I even got a 1925 Dodge Brothers sedan that sat for over 30 years to run! This car has me absolutely stumped. 

 

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Are all the vacuum ports on the carb and intake manifold blocked off? Is the coil a known good unit? 

My worst fear is the timing chain has stretched over time and it's slipped and badly out of time and we might not even know it. That would require draining the coolant, removing the water pump to get to the timing chain. It would be a messy amd time consuming just to check it.

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2 hours ago, Frosty said:

Are all the vacuum ports on the carb and intake manifold blocked off? Is the coil a known good unit? 

My worst fear is the timing chain has stretched over time and it's slipped and badly out of time and we might not even know it. That would require draining the coolant, removing the water pump to get to the timing chain. It would be a messy amd time consuming just to check it.

There is one port on the manifold that is open, I'm going to seal it with solder since it's not being used (it was where the original vacuum choke was hooked up but the tube broke off and I can't get it out, the new Edlebrock has an electric choke so it's not needed anymore).  I've been thinking about the timing issue that you mentioned, that's been creeping up in my thoughts as of late.... I have a mechanic buddy that is going to come over after he returns from out of state, if I can't get it running after that then I'll pull the timing cover and see what that situation looks like.

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It's good to have another set of fresh eyes looking at it. Everything you've described sounds like a timing issue or ignition issue. My money is on timing...either the timing chain or the distributor or both.

Good luck and let us know how things go. Once you find the problem, share some pictures with us.

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Have to agree with Frosty...Definitely sounds like a timing issue to me...One thing to be aware of ...The outer ring on old balancers tend to move around as the rubber deteriorates.... Making the TDC Mark on it completely inaccurate...Realistically the only way to accurately get TDC is to do it manually....

That is assuming the timing set (chain) isn't worn out...An easy way to check it without pulling the timing cover is to use a breaker bar and a socket on the crank bolt and manually rotate the engine...Clockwise with the drivers side rocker cover off as you rotate the engine watch the valves they should move instantaneously...If there is any slack or delay between the valves moving at all...While rotating the crank chances are the timing set has had it and needs to be replaced...(If the timing has jumped chances are there will be some slack in it)

If all that checks OK...With the valve cover still off continue to rotate the engine manually....Do not bump it with the starter...(Will rotate easy if you remove all the spark plugs) Watch the valves on the number one cylinder...When the intake valve opens..Keep rotating..until the valve closes...Slowly continue to  rotate the engine..stick an old pushrod or a pencil or something into the spark plug hole as the piston comes up...When it reaches its highest point with both the intake and exhaust valves are both Fully closed....That is TDC...Look at the damper if the timing nark is not lined up with the 0 Mark on the timing tab that means the outer ring has slipped..You can still use the damper but you have to put you own zero Mark on it then you can use that Mark to accurately set the timing...You can use any terminal on the distributor cap that you want to as #1 just have to put the wires in order counter clockwise starting with the #1 wire...After you decide where you want number one..with the cap on the distributor take a sharpie and Mark the base of the distributor so that it is centered up with the #1 terminal..once you get the base oriented where to want it... Make sure the rotor button is pointing toward that particular terminal....line the Mark you made on the distributor base to the leading edge of the copper contact thingy on the rotor button If everything else is right....Should start and run and be within a couple of degrees of the final timing setting......

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Good catch Two Lane. I had not considered the balancer.

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