[steve25]

While you’re confirming TDC also check how much slack is in the timing chain!

["QUICK-SILVER"]

Originally Posted by steve25

While you’re confirming TDC also check how much slack is in the timing chain!

I'm thinking botched install of a multi keyway timing set.

Would almost bet on it if the TDC mark checks out good.

That would explain the running better with initial timing way off.


It wouldn't be the first
Clay

[NeighborsComplaint]

Honestly, that soot is just a car warming up with the choke on. It's a nothing.

Forget the timing light you have since you are just getting erroneous readings anyway and have no measure of where TDC is to calibrate from.

Here is a simple method to get you in the ballpark. Attach you vacuum gauge to full manifold vacuum. Start the car and when warmed up, adjust your throttle to a comfortable high idle. Loosen you distributor and rotate it to the highest vacuum reading at idle. Back off an inch of vac by rotating the distributor counterclockwise from the highest vacuum setting. Lock the distributor down, readjust your curb idle speed and drive the car listening for any rattling (pinging) at light throttle under load and note if hot cranking with starter is slow (caused by too much advance and resulting pre-ignition kick-back). Both indicate too much advance. If so, retard the timing by slight counterclockwise rotation to another inch less vacuum. Drive and check, repeat until until you have no ping or hard start.

Then move on to your carburetor. With the throttle closed (no throttle input) look own the primary throttle bores at the transfer slots (a single groove that run down the side of each bore/venturi. The top pf the throttle blades should be just slightly lower than top of that slot (carries idle bypass air around the throttle plates to the engine at idle) If the length of the slot above the plates is longer than it is wide, adjust your idle speed screw until the slot appears as a square. This is called "squaring up the transfer slots".

If the transfer slots are already "squared off" at idle, then your problem lies elsewhere, but I'd be willing to bet you will find too much transfer slot exposed in your current condition.

If you were to start the car, in all likelihood it would idle too slow to run as you do not have sufficient idle air bypassing the throttle blades. However, if you raise the idle by the screw, you uncover more of the slot and create a vacuum signal that induces an over-rich condition. This is where you take the carb off, flip it over and add idle air through the secondary idle speed screw concealed under the carb (to keep the "kids" from tampering with it). The easiest way and best place to start is to loosen or tighten the screw until you can slip a .015" inch feeler gauge between the throttle plate and the secondary venturi wall.

Reinstall the carb, start it up, adjust the curb idle speed to normal and then adjust your mixture with the vacuum gauge.

If you find you have to add excessive turns to the curb idle speed screw to get it to idle, you may have to repeat using a, .020" feeler gauge and reinstall but typical that .015" setting will get it right and only a slight curb idle speed adjustment will be needed.

[markpj23]

Originally Posted by NeighborsComplaint

... Forget the timing light you have since you are just getting erroneous readings anyway and have no measure of where TDC is to calibrate from...

I was able to compare my timing light against another and it's fine. Still the question about TDC....

I spent some time adjusting the idle mixture screws today, taking my time and watching the vacuum gauge. Not sure what that 'mechanic' did but I was able to get the thing to stall when the mixture screw was run in all the way. He had told me it had no effect. So much for that guy.....

Anyway, I was able to make a slight improvement but the thing still runs like crap - misses, smells gassy, etc. Nearly impossible to drive at a steady speed without bucking along. Accelerates OK but still crappy overall. No pinging heard at any throttle.

Interesting that during the adjustments I increased the idle speed screw setting to keep it from dying so quickly, then tried to reduce the idle speed to near stall, but it NEVER got to that point even after the screw was backed off all the way.

Originally Posted by NeighborsComplaint

...Then move on to your carburetor. With the throttle closed (no throttle input) look own the primary throttle bores at the transfer slots (a single groove that run down the side of each bore/venturi. The top pf the throttle blades should be just slightly lower than top of that slot (carries idle bypass air around the throttle plates to the engine at idle) If the length of the slot above the plates is longer than it is wide, adjust your idle speed screw until the slot appears as a square. This is called "squaring up the transfer slots".

If the transfer slots are already "squared off" at idle, then your problem lies elsewhere, but I'd be willing to bet you will find too much transfer slot exposed in your current condition.

If you were to start the car, in all likelihood it would idle too slow to run as you do not have sufficient idle air bypassing the throttle blades. However, if you raise the idle by the screw, you uncover more of the slot and create a vacuum signal that induces an over-rich condition. This is where you take the carb off, flip it over and add idle air through the secondary idle speed screw concealed under the carb (to keep the "kids" from tampering with it). The easiest way and best place to start is to loosen or tighten the screw until you can slip a .015" inch feeler gauge between the throttle plate and the secondary venturi wall.

Reinstall the carb, start it up, adjust the curb idle speed to normal and then adjust your mixture with the vacuum gauge.

If you find you have to add excessive turns to the curb idle speed screw to get it to idle, you may have to repeat using a, .020" feeler gauge and reinstall but typical that .015" setting will get it right and only a slight curb idle speed adjustment will be needed.

This makes sense - I'll take a look.

Thanks for the input!

[NeighborsComplaint]

Did the car run that way when you bought it? Have you replaced the distributor cap and rotor or plug wires? Don't overlook the obvious, check the firing order. I am sure everyone has done that once in their life.

[geeteeohguy]

Originally Posted by NeighborsComplaint

Did the car run that way when you bought it? Have you replaced the distributor cap and rotor or plug wires? Don't overlook the obvious, check the firing order. I am sure everyone has done that once in their life.

You need to baseline the car or take it to a mechanic that knows how. The firing order needs verification, as does the distributor installation. The timing needs to be set and the curve checked. And on and on. Very basic stuff.