engine knock

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Feb 22, 2011 | 03:06 PM

fordmanforlife246

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engine knock

whats the first step in problem solving an engine knock? you guys are great with helpin me out. pull the headers off? what do you suggest i do. if its simple i just wanna replace the things the engine needs but if the knock has already done damage i wanna drop a new engine in. this is in a 223 engine i picked up for free btw not my 292.

Feb 22, 2011 | 03:17 PM

Jetcopterpilot

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From: Rossmoor at Seal Beach

Start with the simple things... ie; check the oil level, next I would pull the valve cover, and check the valve lash.... See if any of the rockers are loose, or wobbling check for bent push rods. If it is still running, run some block flush through to see if maybe you have a sticky lifter. Check your timing! Start with the cheap and easy stuff first, eliminate the obvious first, then if you need to, start to tear it down. I had a work truck years ago, after checking all of that, I tore it down to find a piston that had split into 2 pieces horizontally so the lower was pushing the upper up, and then the upper would smack the lower half down.. It could also be a stretched connecting rod. but start simple!

Feb 22, 2011 | 03:50 PM

fordmanforlife246

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okay awesome thanks alot! yes it runs good besides that knock! im gonna pull the covers today and see if anythings loose. sounds like a bad piston. anyways do you guys think this has harmed the engine? (cylinder)

Feb 22, 2011 | 04:00 PM

Ziegelsteinfaust

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From: Chino Hills

If you catch them while they still run it usually just needs an overbore like usual.

Run it till it dies then it could very well window the side of your block so you can see the cam shaft wear issue easier.

Feb 22, 2011 | 04:06 PM

fordmanforlife246

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by overbore you mean by just reshaping the cylinders?

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Feb 22, 2011 | 06:09 PM

patmedic

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From: Divide , Colorado

Overbore means you might have to send the block out to a machine shop to have the cylinders bored (made Bigger). Try doing a cylinder balance test on it to determine which cylinder is knocking. Removing one plug wire at a time with insulated pliers and see if the noise goes away on one particular cylinder. Is it knocking at idle or knocking under load or a higher RPM? Definitely start with checking oil level or for anything loose.

Feb 22, 2011 | 06:35 PM

shortwide

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From: Texas

My brother bought a 64 Falcon when we were roomates in college and I remember him pulling into the driveway and hearing that distinctive knock that inidicated bottom end issues (bad things). It sounded much like two heavy pieces of wood being knocked together.

Lifter noise, on the other hand typically sounds more like something akin to a snare drum....more "tinny" sounding and a lighter tapping. With lifter noise, you can usually hear it coming from under the valve cover, and can usually make it go away or at least minimize it by adjusting your valve lash.

Exhuast leaks also cause a noise that may resemble "tapping".

I know all of this is terribly unscientific, and based on just personal experience, but it's a start and may give you somewhat of an idea of what you might be dealing with.