[STR8SIX]

Heres the situation: our 68 w/302 is still under body repair, but we do drive it around the block every now and again. Started it up last night to drain the flush stuff out of the engine, and it starts "clanking" on the passenger side. Got the timing light out...#1 plug fires intermitant. Pull the 1-4 plugs.../forums/images/icons/shocked.gif. #1 plug is black sooty...#2-#4 is clean (low milage since replace) #1 plug has some brown on 1/2 of the insulator, the other half black sooty. Manual says may be stuck or burnt valve? The "clanking" is a clank, not a ping or "tap". Pulled the valve cover....nothing unusual. Collapsed lifter, broken lifter, bent rod, broken valve stem? Suppose I should start by pulling the top end apart or pull the pan and look at the connecting rods/bearing caps? I pulled the heads while replacing the timing chain last summer. Compression check was good and no cylinder ridges last year.Prolly put a whopping 50 miles on it since then. It was all in working order last week! Honestly!

 

[RTM]

Do another compression check first. Have you or anyone else been working with small bolts around the carb?

 

[sharkmouth]

don't mean to split hairs...but it may help to know....

a "clank" to me sounds like a wrench against a steel pole (like a kids swingset)...tuning fork-ish, and nothing INSIDE an engine Ive heard clanks.

The sounds inside an engine have a more solid quality that doesn't "ring"....a bad main bearing or piston slap sound like a STRONG smack of a hammer on an anvil, for instance...like a "clack"

A rod bearing sounds "smaller", like a kids metal headed hammer against an anvil

Not trying to cute....this info may help you and us to help you

The clanging sound I described first is usually caused by vibration of the engine moving external parts causing an external noise......heat shields for example...and for me, are usually more of a nuisance.

 

[STR8SIX]

my bad. Clank is not the term.Louder and stronger than an ignition ping. No external loose pieces. It is most noticable in the intake area, which leads me first to a lifter problem. Plan on doing a comp check tonight. Dont think anything went down the carb. /forums/images/icons/smile.gif hehe, a BB down the carb. Not since high school.

 

[fordnut]

What do you mean by" Flush stuff out of the engine"?
Are you useing something to flush the oil passages? If so, this might be the problem.....
You might have loosened up some grunge and it is stuck somewhere, like on top of a piston, in a lifter, or one of a million other places.....
That stuff loosenes stuff that is better left alone....
I would drain that stuff out, change oil filters, refill with clean oil, then see what happens....
If this is not what you are doing, please disregard this post.......

 

[STR8SIX]

comp check went well over weekend. 150-145 on #1-7. #8 came in at 140lbs. I'm torn between pulling the pan or the heads. Coin toss.

 

[RTM]

What is your oil pressure at? Like the previous post you may have caused something to lodge in your oil pump causing it to fail. My friend had this happen to him after he refused to clean out the pick up. He was lucky, he didn't harm anything. Have you taken the valve covers off and rotated the motor over and watched all the valves go up and down properly? Its not sounding to good at this point.

 

[STR8SIX]

needle on gauge is lower than usual. Usually in the middle, but is lower now. Suppose I could take the psi gauge off the six cylinder since its not on the road and hook it up. I'll give it a shot.