258 Misfire
lloydwithAf
Jeeper
I finally got around to putting my engine back together after a few valves seized and bent a few pushrods on its maiden test run after sitting for a decade. I had a valve job on the head completed(decked 0.010) and installed a new comp cams 262 cam and double chain timing set. I pulled some pushrods out of an 83 AMC 258 i6 / 4.2l I had laying around and put it into my 82, they were 0.50” longer. Milling shows the pushrods I installed are the correct ones, so my assumption is whoever rebuilt this engine in the past used an older model pushrod length. When I fired it up, the timing light is showing a miss approximately every 1 in every 3 or so revolutions. I am basing the miss on the sound of the engine and the flashes on the timing light “skipping” every 3rd or so flash on the #1 plug wire.I ran a compression test and the cylinders are all in the 130-140 range so I think that rules out valves being slightly open.
My thoughts are
1: cheapo HEI is crapping out already(with its 5 miles on it).
2:Timing set is off a tooth or two, even though I double checked it when I installed.
3:somehow the slightly longer pushrods(correct length for the year) are affecting it.
I know I need to check pushrod preload. I will have some time this week to do it.
Any suggestions or recommendations would be greatly appreciated!
My thoughts are
1: cheapo HEI is crapping out already(with its 5 miles on it).
2:Timing set is off a tooth or two, even though I double checked it when I installed.
3:somehow the slightly longer pushrods(correct length for the year) are affecting it.
I know I need to check pushrod preload. I will have some time this week to do it.
Any suggestions or recommendations would be greatly appreciated!
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