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- #21
@Weber Sarge - back to shop now. Stock filter, OEM replacement due in tomorrow. Will check fuel inlet next. Rechecking vacuum now
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vacuum leak-- prob in the manifold---My '74 Southern Charm is (still) giving me a bit of a fit (occasionally which is the most frustrating part). This has been an on and off problem. After the motor warms (2F SN 882263-I think it is a mid '76 motor), traveling up to 12-15+ miles with some highway speed) - the truck will begin to run poorly when I try to accelerate - like it is starved for fuel (mechanical pump, good pressures). The timing is not off(non-use distributor with points) . Odd thing is - it does not do this every time I drive more than that, but most of the time.
If I pull over and stop, sitting on the shoulder, idling, I can manually throttle it up - not under load - and it throttles up fine (motor revs like you would expect) - but if it is under load (in gear) - at a stop sign, let the clutch out, try to get up to speed - anymore than 5-10% throttle and the motor will stop responding and it will not accelerate properly. From a stop, I can let it idle up to speed, shift into 2nd, let it idle up a bit more and give it just a bit of gas, shift into 3rd - and I can get down the road as a last resort. I just cant use the accelerator pedal or it acts like I am not giving it any gas.
Additionally, even once it starts to hesitate - I can cruise with minimal throttle at 40mph - 50mph, and you do not feel the hesitation - UNTIL YOU TRY TO HARD ACCELERATE. With a very light acceleration, it will slowly respond without the obvious hesitation.
I am running a Weber 38 from TPI (no sight glass, no fuel return line, electric choke - could this be coming into account after it warms up?). Fuel lines & filers recently replaced , plastic tank by the PO. It has a Mallory ignition coil which the PO installed (see pic). The inside of the dist cap is clean - no water / moisture. @lextechautomotive has tried to get it to run poorly, but it hasnt yet. Glenn recommended I replace the Mallory ignition with a stock coil & resistor(I have the resistor - but I haven't checked it). Additionally - it does not matter if it is 60F or 94F outside.
I've checked and it appears there are multiple coil PNs. Is there a difference between them? Is there a coild specification (Voltage, spark, Cap rating....?) Any other ideas that I could check / try to eliminate the coil / resistor / something else?