help knock in engine after plugs changed

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Mar 11, 2007 | 03:45 PM

atvohio

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Joined: Jun 2006

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help knock in engine after plugs changed

92 F250 with a 460 I just bought about 3 weeks ago. Ran strong with no misses or smoking. Gas milage was really bad so I thought a good tune up would help. Changed plugs and wires. Plugs looked awful like they had been in a long time. Had problem with one plug. It broke off with nothing sticking out. I drilled it out and got it out with an easy out. I think the part of the electrode and some ceramic went inside. My buddies didn't think it would hurt anything so we went ahead and put in the new plug. Also changed the distributor cap and rotor button. When I started it up to try it out it run like it is kind of out of time and there is a loud occasional knocking sound like something is loose in the motor. It will only idle for about a minute to a minute and a half and die. I took out all the plugs and felt for compression and they all blow and suck pretty hard. I also stuck a magnet down the hole where I broke off the plug and all I could get out is some metal shavings. I think I have my firing order right 1 5 4 2 6 3 7 8. Anyone have any ideas what I should do now?

Mar 11, 2007 | 05:05 PM

arctic y block

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Joined: Sep 2006

Posts: 14,325

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From: Island Southeast Alaska

It could be a lot of things. Bent valve (compression test)
Plug gap. Plug gap closed. Bad or wrong plugs. etc
Sounds like the firing order is off from what I can here, from here.