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Discussion Starter #1
I have a 351 4v ram air on a 73 CV and it misses. I have changed points, dist cap and rotor, coil, spark wires, plugs, checked timing and chased grounds throughout. I cannot make it run right When I bog it, it seems to do better than just cruising. I have new gas tank, lines, hoses, and filters. I checked each wire with a spark test light and every wire exhibits a misfire every so often. There is no pattern or rythum to the miss. Can anyone give me some clues as to what might be causing this. What component might be sporatic? The distr is a mech advance dual point and I'd like to stay with the points. All ideas appreciated.
 

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Is there any slop in the distributor shaft? did you gap the plugs before putting them in? not too wide? Away from the ignition system, hows the valve train? I'm stretching here, but when you bog the engine, the cylinder pressures go way up. Wonder if that's sealing something.

Joel
 

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when you changed the points how did you set them? put a dwell meter on the distributor and check the dwell. way more accurate than feeler gauge. :bigthumbsup
 

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Discussion Starter #4
Thanks for the response.
All plugs were gapped to .032-.035. Internally, I dont know the condition of the valve train. I guess I need to pull the engine and rebuild it but I'd like to wait until summer if it will last. As for compression, there is about 20psi difference between the left bank and the right, with no single cylinder varying very much. Comp readings running from 120+ on right to 140- on left. I am told that is about right for the long duration cam that the CJ has. Anything else?
 

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check the battery voltage when runing if the voltage regulator is not charing right this can in some cases cause a misfire randomy is when dose the skip occur all of the time riding down the road pulling or just ramdom at idle one thing i would do is at night crank car and let idle pop the hood and see if one of the wires is arking to ground
 
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