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Engine knocking

Posted: April 11th, 2015, 10:51 am
by bybirius
Hey Guys,
Got my engine together and have been running it lightly for a short time now. As I run through the gears, I am getting a knocking sound. It begins knocking in first gear just as I'm about to shift to second, then again as 2nd is topping out and about to go to third, it knocks, then the same with third and again as I top out in fourth. I'm running an FS electronic ignition with auto advance and when I retard the timing it doesn't hardly knock but then is obviously very sluggish from idle and spits and backfires, etc. I've been thinking it's a timing issue, but with it sitting idling the engine sounds just fine but when I short plug wire 3 with a screwdriver to a head bolt, I hear the bump bump bump bump.
What do you think? Am I climbing under there again, pulling the pan and hunting babbits?

Re: Engine knocking

Posted: April 11th, 2015, 1:03 pm
by spectria
bybirius wrote:Hey Guys,
Got my engine together and have been running it lightly for a short time now. As I run through the gears, I am getting a knocking sound. It begins knocking in first gear just as I'm about to shift to second, then again as 2nd is topping out and about to go to third, it knocks, then the same with third and again as I top out in fourth. I'm running an FS electronic ignition with auto advance and when I retard the timing it doesn't hardly knock but then is obviously very sluggish from idle and spits and backfires, etc. I've been thinking it's a timing issue, but with it sitting idling the engine sounds just fine but when I short plug wire 3 with a screwdriver to a head bolt, I hear the bump bump bump bump.
What do you think? Am I climbing under there again, pulling the pan and hunting babbits?
Your description sounds like piston knock (rattle)?

Re: Engine knocking

Posted: April 12th, 2015, 6:06 pm
by bill worden
It may just be time to go down another babbit hole. :|