zero compression
https://youtu.be/7_FbMjZ1Q9U
Last edited by augiedoggy; Apr 19, 2021 at 08:27 PM.
I'm not 100% sure, but that might be a ported vacuum port on the carb. You can test it with your finger. You want to move it to a manifold vacuum (you could even put it on the capped port on the manifold just to test).
You appear to have removed your choke heater. The choke will never open, unless I'm missing something.
anyway can't time if it shuts off. I cranked it to zero, dropped dizzy in at 1:05 meaning it's point right at one almost and about to head to 8. I read somewhere it's best to drop it in between 3 and 1. anyway, I also read you can't crank right at tdc 0. best to crank ADVANCED 4-8 degrees out (which are the numbers to the right of zero if i'm facing the driver's seat from the front of the car. Haven't done all that yet. could also be my hoses on my carb since I just plopped it in there.
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Get a dial-back timing light if you don't have one -- or go Cadillac and get an Innova 5568 (https://www.summitracing.com/parts/ino-5568). Don't buy Harbor Freight or some other super-cheap light as you want reliable strobe circuitry. The Innova is nice because it can read RPMs, voltage, and dwell, as well as timing. If you don't have the Innova, you'll need a dwell meter too if you have a conventional points/condenser distributor (non-HEI) . You'll also need to have a vacuum gauge for making carb adjustments.
This bulleted list is intended to get your timing and carb set up to start and run relatively well – not necessarily to optimum, high performance.
- Remove the vacuum hose from the distributor vacuum can and plug the end of the hose - no need to plug the canister as there's nothing there to seal off.
- Slightly loosen the distributor hold-down so you can move it but with a little effort.
- Hook up the timing light and dwell meter. (Dwell is the amount of space between the points contacts when they are at their most open.)
- Start the engine and adjust the dwell to read 30°, +/- a degree. This only applies to points/condenser; HEI distributors do this electronically.
- Rotate the light's dial or press the up/down buttons to set the light at 34°, then pull the accelerator up to 2500-3000 rpm.
- Aim the strobe at the timing tab and rotate the distributor until the timing mark on the balancer lines up with the 0 zero mark on the tab. If you go too far in the wrong direction, the engine will run super rough and may die. Rotate it back approximately the same amount you moved it but this time rotate the other way to line up the mark.
- Allow the engine to return to idle, shut down, reattach the vacuum hose to the canister, and cinch down the distributor bolt.
Now that your timing is set pretty close to optimum, you need to adjust the carb.
- Screw in the mixture screws until they gently seat and then back them out 3 or 4 full turns.
- Hook the vacuum gauge on a constant-vacuum hose coming from the carb or the main vacuum fitting on the manifold behind the carb mounting.
- Start the engine and adjust the idle to spec (600 - 800 rpm is a good guess if you're not sure of spec).
- Now adjust the mixture screws by screwing one inward in 1/4 turns until you see the vacuum needle go lower. Then unscrew it so the needle goes to its highest setting. Do the same with the other screw. Lastly unscrew each one 1/2 extra turn.
- Check the idle speed and adjust again if necessary.
Last edited by barkingrats; Apr 19, 2021 at 11:34 PM.
anyway can't time if it shuts off. I cranked it to zero, dropped dizzy in at 1:05 meaning it's point right at one almost and about to head to 8. I read somewhere it's best to drop it in between 3 and 1. anyway, I also read you can't crank right at tdc 0. best to crank ADVANCED 4-8 degrees out (which are the numbers to the right of zero if i'm facing the driver's seat from the front of the car. Haven't done all that yet. could also be my hoses on my carb since I just plopped it in there.
The Innova 5568 is great!
Remember I also changed the carb tonight to the new one and all is capped off. Will only connect the vac advance and cannister plus brake booster already connected. check out that video. I never thought to use the multimeter though. Any links for a quick study? thanks for all your help.
Here's my go-to video for using a timing light. If you have the Innova light I linked to, you can do without the tape, but the tape is a great thing to have anyway.
EDIT: I can't find an initial timing video that does anything different than what you must already be doing, and basically requires a running engine. Hopefully with the idle screw, and some carb vacuum port covers, you can get the engine idling without intervention. There is a way to set initial timing with a multimeter on the coil, but it requires a points distributor.
This video shows setting the initial timing (only, which is incomplete, but will get you started), using a timing light very similar to the Innova 5568 (probably a rebrand of the same electronics). Anyway, it shows the function of the delay feature, with added timing markings.
Last edited by Bikespace; Apr 21, 2021 at 12:45 AM.
Last edited by barkingrats; Apr 21, 2021 at 12:57 AM.













