1968 Impala won't start

dabunk

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That 28-32 deg is the dwell angle, the amount the dizzy should turn while the points are closed enough for current to flow through the coil primary. If you want to set the point gap mechanically, the rubbing-block for the movable arm of the points must be on the tip of one of the dizzy cam lobes. Setting gap is less accurate then using a meter and setting dwell angle, but good enough.
Good enough to see it start and run
 

stu

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Does it have a ballast resistor?
 

Chuck

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So, I picked up new points, condenser and a feeler gauge. Do I tighten down the screws and use the dwell screw to adjust the gap?
 

Mobile Dan

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I don't remember how much "range " the dwell screw has, I would try to get it centered and then install points "closed" and the rubbing-block for the movable arm of the points on the "ramp" of one of the dizzy cam lobes.
Then adjust the dwell screw to see what happens after you move the cam to "tip position".
 

billr

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Yes, use only the screw with the hex. The points have small dimples on the underside to act as dowels for locating the point assembly in a precise position.
 

Chuck

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It runs!! Runs like crap, but still runs. Now I just need to get a dwell meter so I can get the correct gap. Thanks for everything folks. Much appreciated.
 

billr

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You say it ran OK before? Has the dizzy been removed from the engine or rotated since then? Are you sure you have the plug wires connected in right firing-order? That would be 1-8-4-3-6-5-7-2, and the dizzy turns CW looking down on it. Odd-number cylinders are on the driver-side (#1 in front of engine) and evens are passenger-side (#2 in front). Do you have a timing light?

If this present "runs like crap" problem is only because of point gap, my guess is the gap is too big; try closing it up a bit.
 

Chuck

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You say it ran OK before? Has the dizzy been removed from the engine or rotated since then? Are you sure you have the plug wires connected in right firing-order? That would be 1-8-4-3-6-5-7-2, and the dizzy turns CW looking down on it. Odd-number cylinders are on the driver-side (#1 in front of engine) and evens are passenger-side (#2 in front). Do you have a timing light?

If this present "runs like crap" problem is only because of point gap, my guess is the gap is too big; try closing it up a bit.
It ran great before. I believe you're correct about the gap. I'm gonna wait till I get the multimeter with dwell that I ordered to get here so I can get it all correct at once.
 

billr

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Do you know how to do that dwell adjust? You do it with the engine running. Slide the little window on the dizzy cap open and reach in with a hex-key. Disconnect the vacuum advance while you are doing this, or that breaker plate and the screw you are adjusting will be moving around; hard to get the hex-key in the screw head or to keep it in.

NOTE: There is often a voltage on the points arm and that screw, high enough to be "entertaining". Be sure to insulate the part of the key you will be holding with some tape...
 

Chuck

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Do you know how to do that dwell adjust? You do it with the engine running. Slide the little window on the dizzy cap open and reach in with a hex-key. Disconnect the vacuum advance while you are doing this, or that breaker plate and the screw you are adjusting will be moving around; hard to get the hex-key in the screw head or to keep it in.

NOTE: There is often a voltage on the points arm and that screw, high enough to be "entertaining". Be sure to insulate the part of the key you will be holding with some tape...
Thank you. I will keep that in mind.
 

paulo57509

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It runs!! Runs like crap, but still runs. Now I just need to get a dwell meter so I can get the correct gap. Thanks for everything folks. Much appreciated.
Typically, GM points out of the box use to be pretty close. Also, make sure you remove all the old distributor cam lube and wipe on some fresh grease. Put a dab on the rubbing block of the point set as well.

If you can't find a dwell meter, you can do this to get you by until you find one (assuming the timing was properly set before hand and you didn't rotate the distributor):

Disconnect the vacuum advance and plug the rubber hose.

Connect a timing light, start the engine and note the reading on the timing tab (don't take the reading with the engine above idle speed).

Open the window in the distributor cap and fish around with a hex driver for the socket headed points adjusting screw.

Adjust the point gap by noting the timing mark on the balancer/timing tab - set it until the mark corresponds to ~ 4 or 6-degrees BTDC.
 

grcauto

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It ran great before. I believe you're correct about the gap. I'm gonna wait till I get the multimeter with dwell that I ordered to get here so I can get it all correct at once.
If it only needs the points adjusted you can do it without a meter. Turn them in until the engine starts to stumble and back off 1/2 turn and it'll be good.
 

Chuck

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Typically, GM points out of the box use to be pretty close. Also, make sure you remove all the old distributor cam lube and wipe on some fresh grease. Put a dab on the rubbing block of the point set as well.

If you can't find a dwell meter, you can do this to get you by until you find one (assuming the timing was properly set before hand and you didn't rotate the distributor):

Disconnect the vacuum advance and plug the rubber hose.

Connect a timing light, start the engine and note the reading on the timing tab (don't take the reading with the engine above idle speed).

Open the window in the distributor cap and fish around with a hex driver for the socket headed points adjusting screw.

Adjust the point gap by noting the timing mark on the balancer/timing tab - set it until the mark corresponds to ~ 4 or 6-degrees BTDC.
Thanks. I'll give that a try.
 

nickb2

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sadly the rod from what I think is the power pump jet obscured the last 2 digits


But sure has a lot of fuzz on it. That carter needs a deep soak ;)

I know I am overthinking as usual, but here is a link to some cool resources to revamp that SWEETY OEM quadrajet. Very rare, plz keep it

heres link

 
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