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  #1  
Old July 1st, 2019, 08:25 AM
Hartgreen Hartgreen is offline
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Default Tuning Help

Ok so I just got my Carb rebuilt and replaced the coil, points and condenser. It seems to be running mostly ok but it has no power up hills and it seems rough at high speed. Im also getting some dieseling when I turn off the motor combined with white smoke out of the Carb.

My research shows that its probably timing, fuel mixture or maybe crap in the cylinder. I had a timing light and it wouldnt read through the insulated spark plug wire so I used a cut piece of regular sparkplug wire between the plug and the distributor. I still couldnt get a consistant flashing light for some reason. I gave up on the timing until I could figure out something that would work. Someone said that it could also be vacume pressure issues with the fuel pump? Dont have a vaccum tester so I dont know if thats right. Im really frustrated and I could use some guidance. I feel like it could be any number of things and I dont want to make one thing worse while trying to figure out the actual problem.
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Old July 1st, 2019, 10:57 AM
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The only other way to time it would be using a vacuum tester to a port on the intake manifold, rotate distributor to max reading and back off slightly, or tune it by ear. You should be able to get an inexpensive one at harbor freight. I have never had much luck using a timing light on these waterproof/shielded distributors.
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Old July 1st, 2019, 01:47 PM
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Are you powering the timing light with 12 or 24 volts? A normal light will need 12 volts.

Did you cut away the civilian wire insulation and fold the core wire over the end and then stick it in the military spark plug and wire? If you don't have the middle core sticking way out, it is hard to make work.

Vacuum does work real well. Just turn the distributor back and forth until you get the peak vacuum reading. Then readjust the idle and air/fuel mixture setting and play with the timing until at idle rpm, you have peak vacuum.

If you get all that set, the truck runs great but still chug ah chug, chug's when you turn it off. Lower your idle a bit and try again. Repeat until it starts, idles and turns off without extra drama.
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Old July 1st, 2019, 04:09 PM
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i have had vacuum leaks cause dieseling. Check or replace all the line vacuum lines. My problem that time was the vacuum line at the windshield wiper switch.

Fuel pump could be an issue at high speed if it doesn't move enough fuel. I test by filling a 16 oz water bottle. should only take less than 15 seconds.

I have set timing with vacuum as described. Works easy. Had to because the timing marks were out of alignment.
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Old July 2nd, 2019, 06:01 AM
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I set my timing several years ago with a light. I have one of those military boxes of adapters which allow you to connect to the shielded plug wires etc.

My truck doesn't diesel (it wants to!) and I have the timing set a lot higher than the spec. It does ping a little on hard acceleration (Hey, wait, isn't every time that we start moving "Hard Acceleration" in a Tornado engine? ).

Some people set the timing (in this and other conventional point/condenser engines) by ear. Engine running, loosen the adjustment on the ignitor slightly, enough to move it but it stays where you put it. As you advance the timing, the engine should run a little faster.

Seriously, I have started using 89 octane ethanol free gas for the obvious reason. I don't mind a little pinging (not detonation) because I know that I am getting the most out of the engine.

I am a 100% stock etc. person; it's just easier because it matches the TMs for me.
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Old July 2nd, 2019, 07:41 AM
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Kwai, I was thinking of your white truck with the fiberglass top at the ranch when I wrote my reply. I remember the vacuum wiper leak and I also remember messing with the idle speed to get it to actually turn off. Right?
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Old July 2nd, 2019, 09:37 AM
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yes. But the final solution was to fix the vacuum leak with new hose instead of a plug whittled from a stick found lying next to the truck.
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Old July 2nd, 2019, 01:27 PM
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Quote:
Originally Posted by kwai View Post
yes. But the final solution was to fix the vacuum leak with new hose instead of a plug whittled from a stick found lying next to the truck.
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Old July 2nd, 2019, 03:01 PM
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Field Expedient repair
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Old July 2nd, 2019, 03:36 PM
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Quote:
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Field Expedient repair
I hear ya...
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