Replacement vacuum advance can for 318 distributor

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Mike you ever see that with a petronixs unit? I know you have run them for a long time.
 
Same here. You can mess with the gap a bit for more or less dwell, but .030 works fine.
 
Plugs are autolite 3926. Which is just a 66 with 5/8" hex. Pulled them, were very clean and looked a bit too lean on the left bank.

I checked for vac leaks, pinched the pcv hose no change. Carb mounting nuts tight and tq-checked the intake manifold bolts.

The issue seems to happen at any rpm below about 1k. Then as you open the throttle it cleans up, get smooth and timing mark becomes steady. I got it idling OK at around 750 rpm, but it was still intermittently misfiring. Even an occasional pop through the carb. Timing is at around 15degrees initial, hard to tell exactly with the erratic idle. I checked transfer slot exposure and lt was a little past square, towards rectangular on the long side at my current idle screw setting.

I played with the air mixture screws a bunch and they didn't seem to affect the problem. Engine would response with drop and increase in idle as expected as I manipulated them, but no change to the overall quality and missing.

Pulled a couple plug wires and got some decent spark, so at this point I am kind of going in circles.

Maybe there is an obstruction in one of my air bleeds. I guess next I will blow them out with compressed air.
 
Oh and spark plug gap is at 0.040", been running that with the Pertronix for a while no issue. Fuel is fresh from a couple days ago. New gas tank. Freshly rebuilt motor that was idling fine before.
 
smokinnjokin said:
Oh and spark plug gap is at 0.040", been running that with the Pertronix for a while no issue. Fuel is fresh from a couple days ago. New gas tank. Freshly rebuilt motor that was idling fine before.
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You said you have a 318. What year? Is it a LA 318 or a Poly? (I'm looking at your avatar)
 
Just tried to take it for a run and now it is garbage across the rev range. I have cycled three ignition coils through it, all bench test good numbers but it is possibly they are all bad, shelved them originally because they were suspect. Now i am worse of than when I started.

Clogged idle circuit would not cause the car to run my garbage across the rev range, but swapping in a bad coil would. Going back to the original ignition coil (summit 60k canister, 1.5 primary with ballast resistor).

Stay tuned.
 
smokinnjokin said:
Plugs are autolite 3926. Which is just a 66 with 5/8" hex. Pulled them, were very clean and looked a bit too lean on the left bank.

I checked for vac leaks, pinched the pcv hose no change. Carb mounting nuts tight and tq-checked the intake manifold bolts.

The issue seems to happen at any rpm below about 1k. Then as you open the throttle it cleans up, get smooth and timing mark becomes steady. I got it idling OK at around 750 rpm, but it was still intermittently misfiring. Even an occasional pop through the carb. Timing is at around 15degrees initial, hard to tell exactly with the erratic idle. I checked transfer slot exposure and lt was a little past square, towards rectangular on the long side at my current idle screw setting.

I played with the air mixture screws a bunch and they didn't seem to affect the problem. Engine would response with drop and increase in idle as expected as I manipulated them, but no change to the overall quality and missing.

Pulled a couple plug wires and got some decent spark, so at this point I am kind of going in circles.

Maybe there is an obstruction in one of my air bleeds. I guess next I will blow them out with compressed air.
Click to expand...
Kind of what I am thinking, rev it and close the choke so it almost stalls might clean them out. Old school there.
 
Just to let you know where I am going with my questioning. I put in some Autolite plugs in my 273. Never could get it to idle right. By their conversion chart, they were too cold. I put some warmer Champions in and the difference was night and day. I chased the issue around for 2 summers. Just thinking outside the box.
 
toolmanmike said:
You said you have a 318. What year? Is it a LA 318 or a Poly? (I'm looking at your avatar)
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Its a 360, comp xe262 cam, headers, eddy intake and carb. The points distributor on it was a 318, but about halfway through the thread I swapped for a electronic unit from halifax hops. I took the pertronix from my points distributor and swapped it into that one.

Now my vac can issue is solved, and I have a serious idle problem.
 
toolmanmike said:
Just to let you know where I am going with my questioning. I put in some Autolite plugs in my 273. Never could get it to idle right. By their conversion chart, they were too cold. I put some warmer Champions in and the difference was night and day. I chased the issue around for 2 summers. Just thinking outside the box.
Click to expand...

Good thinking, but these are hotter plugs, and it ran well with them up until my vac can diaphram ruptured and i did this distributor swap. Looked clean when i pulled a few this morning, albeit a little lean.

To precisely describe the issue, the idle fluctuates by as much as 70 rpm (at around 750) and the timing mark is jumping around randomly, intermittently by 5-6 degrees. It acts like the timing is randomly retarding and advancing. Occasionally while idling it will just quit, or backfire through the carb.
This has to be distributor related.
 
smokinnjokin said:
Good thinking, but these are hotter plugs, and it ran well with them up until my vac can diaphram ruptured and i did this distributor swap. Looked clean when i pulled a few this morning, albeit a little lean.

To precisely describe the issue, the idle fluctuates by as much as 70 rpm (at around 750) and the timing mark is jumping around randomly, intermittently by 5-6 degrees. It acts like the timing is randomly retarding and advancing. Occasionally while idling it will just quit, or backfire through the carb.
This has to be distributor related.
Click to expand...
Sounds like switching it back to a known good ignition would be the way to go.
 
Take a picture of the distributor from the top down with the cap and rotor removed if you can. Also are the springs ok in it when you had the plate out?
 
The points distributor on it was a 318, but about halfway through the thread I swapped for a electronic unit from halifax hops. I took the pertronix from my points distributor and swapped it into that one.


OK the petronix plate for a points is in a electric housing, I am assuming you are using the cam plate from the points set in a electronic housing? I know it wont work on the electronic points plate unless you are using the stock reluctor? Just trying to get a hold on this. Have to ask your not using a mopar reluctor to drive the petronix unit are you?
 
Hey Joe describe all of what is in the ignition now so I get a base line. distrib, ECU, Ballast etc.
 
Ok, so i took the top plate off the points distributor and installed that onto the electronic distributor, so that i could mount the pertronix. The only thing I had to modify, was drill an inner hole to mount the curved-arm vacuum can. I used the mounting plate from the electronic distributor as a template to drill the new hole.

I swapped the original coil back in, and it immediately idled a lot better, but deteriorated as it heated up. Great power through the range and acceleration, as soon as i opened the throttle a bit. In desperation, i tried opening the air screws WAY open, to like 8 turns, and that helped smooth the idle immensely.
I immediately went home, blasted out the air screw passages with carb cleaner and put them back in. Still, for it to want to idle decently I need like 4-5 turns out and it is rich enough to burn my eyes. And it still is not strong, putting in gear drops idle from 750-500 and its chugging.
 
Strange. Had a friend that had a carb bleeding over that acted kind of like that. (too much fuel pressure)
 
halifaxhops said:
Hey Joe describe all of what is in the ignition now so I get a base line. distrib, ECU, Ballast etc.
Click to expand...

electronic ignition, curved by you, 20 mech at the crank. 15 vac at crank.
Pertronix ignitor 1 (replaces points).
Stock-style 1.5 ohm resistor.
summit 1.5 ohm coil.
New points wiring harness. Coil is getting pretty hot, ballast resistor is still putting out around 12 since my system charges at 14.5-15. Have it mounted upright.

With where I left off on my last post, its running a lot better. Timing mark has stabilized at idle to within a couple degrees. Static timing is at 17. But i am still crazy rich on the air screws for it to idle right, 4-5 turns.
 
toolmanmike said:
Strange. Had a friend that had a carb bleeding over that acted kind of like that. (too much fuel pressure)
Click to expand...
Just checked, my gauge is for high psi fuel injection so not sure how accurate it is a low pressures, but it showed a steady 4-5psi, just off the needle.
 
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