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hi, i am a first time poster and a beginner as well. my truck is a 1963 1/2 ton slant six 4 spd, single barrel carb which has rebuild date stickers still on it. i was told by the previous owner that the motor was rebuilt. looking at it, if they didn't rebuild it, they had it out and they painted it.
when i got it, it ran ruff and did not want to idle. i put a petronix module and coil in, new plugs, the old ones looked clean and new but i changed them anyway, new cap and wires, and new ballast. that made no change what so ever.
setting the timing has been impossible. although the marks and tab are visible when not running, they don't come together when running. i have the distrubitor turned all the way clokcwise just to get it to run like described
i've trien various positions with the firing order changing the wires one space in both directions and the best place has been the 1,4,2,6,3,5 order.



so what is wrong. i've thought bad distributor, distrubitor in wrong, timing chain off by a tooth or two? what do you guys think?

Start with basics. Valve cover off, Check valve lash clearances. TDC and check position of rotor for # 1. With valve cover off you can determine what the valves are doing. BASIC, BASICS first. SL 6 Distributor gear can be out a couple of teeth. It has a gear on it.

#1: When the timing doesn't make sense, always verify TDC. Get a piston stop and use it to find top dead center on #1. https://www.summitracing.com/parts/crn- ... /overview/ Always disconnect the battery and turn the motor by wrench when using a piston stop. Thread the stop into the #1 spark plug hole. Turn the engine clockwise until the piston hits the stop. Mark the damper. Turn the engine counterclockwise till the piston hits the stop. Mark the damper. Halfway in between the marks is true TDC.
Then you will know if the timing mark on the damper is accurate. They can move, because the outer ring of the damper (where the mark is located) is a separate piece from the hub of the damper, held together by rubber.

#2. THe dist has a vacuum advance. suck on it (with your mouth or a vacuum pump) If air flows freely thru it, it is shot, replace it. If it allows you to build suction, check for movement of the breaker plate when you suck on it. If it moves, good. If not, free it up or replace the distributor.

#3: When you check the timing, make sure that the vacuum hose or tube is disconnected from the distributor and plugged. Your timing at idle is with NO vacuum advance. Connect the tube after all the other problems are solved.

#4: check the valve lash. Your slanty has solid lifters, not hydraulic. The lash can tighten if the valves wear away the seats from unleaded gas. Lash too tight will make it miss and run horribly.



Handle these items and get back to us. Good luck, Joel

ok, thanks for all the info. i'm off to find a piston stop. i'll post my results.

hey guys, thanks for the great advice. turns out it was the distributor. when the motor was rebuilt, they installed the distributor a couple teeth off. pulled it out and rotated it and presto! a nice smooth running slant six.
so anyone have a super six 2 barrel intake for sale?
any thoughts on if its i a better idea to go 4 barrel? i'm not building a race truck but i would like to get more power out of the slant six and still keep it as a daily driver.

thanks, its great having this source of info

Why settle?

too kool.