hey guys, i have a question. i have a stock 292 in my 64 f100 and well, when it idles, i cant tell if its got a lope or a miss. I checked all the plugs to see if they are firein an they are and no eratic sparks. the reason i know that they are all firein is cause my ignition tester only fires or flashes when the plug fires(snap on ingition tester). do these motors have a lope or slight lope at idle that would be mistaken for a miss?

 

hey number dummy, airharley, anyone. can you help? i ont know what it is if its a miss or the motor is lopeing.

 

A stock motor would not have a lope like you hear with a performance cammed engine. At idle it should have a nice steady drone. It sounds like you have checked the ignition system, plugs firing, good points and proper gap, cap and rotor in good shape, no crossfires (best seen after dark with motor running). When you check the timing with your light does the timing move in sync with the lope?
Look for a vacuum leak at the intake gaskets. It may also be helpful to check the manifold vacuum. Easiest place is at the very back of the manifold.
Another possibility could be a distributor with worn bushings and/or gear.
The scariest idea I have is perhaps a cam lobe(s) that is going flat.

 

thanks 46. the way i have cheked the timing is just by setting the rotor to number 1 on the cap and the damper on 10 degrees before top dead center to the timing mark. thats all i have done. could it be my timing chain? as far as i know the motors never been torn down. never thought about the darn timing chain. could that be it?

 

With the motor running at idle, vacuum line to the dizzy disconnected at the carb, and carb vacuum port plugged, put timing light on number one plug and see what where the timing falls on the timing pointer. As you are looking at it, does it vary consistenly with the lope, or is it like it should be, steady at one point of advance. Adjust your distributor if needed to achieve 8-10 degrees advance.
From your description of the motor condition the timing chain and sprockets are surely worn. That will retard your cam timing and negatively affect performance. I am not smart enough to be able to figure out if a retarded cam timing would produce a lope, but sounds conceivable.
One more easy thing you can do is check and adjust the valve clearance. If an intake valve has far too little clearance at the rocker, it could be remaining partially open.
Rather than going from one relatively minor thing to another, maybe the best idea is to do an assessment of some of the noninvasive kinds.
Compression test cylinders
Do a leak down test on cylinders
Put in new timing chain and sprockets
Adjust valves
Check for bent pushrods
Use that timing light and see what the full advance is and at
what rpm.
Pull distributor and gauge its wear
Check manifold vacuum and look for leaks in hoses, at intake gasket,
carb gasket.

 

ok guys, check this. I took the truck to a shop and had the timing checked.( dont have a timing light) and the tech came back out to me and said it was 25 degrees advanced. he reset it to 10 degrees and wow, what a diference. readjusted the carb and wow. what a diference. the higher rpm sputter i have been fighting disappeared. pulls better. And my miss i have been dealing disappeared dang near all of it. I called my dad(he used to work on dave mosnys puller trucks) and asked him how bad that was. he said that i am really really lucky i didnt burn a hole in the piston or busted a rod.