engine knock bad!!

71dusterjon said:
no i just took the intake, headers, and valve covers off to paint them. i then rerouted the crankcase vent into the exhaust and changed spark plugs. i haven't unbolted anything else from the motor.

the time difference between the two videos is like 30 seconds.
jsut dont sound like its running on all ten, I could be wrong, go out , pull two easy plugs from each side, and see what they look like, dont think its in the top end, I jsut hope you didnt drop anything in the cylinders.
dont crank it anymore till you find someting
 
you're thinking something fell in the runners and is in the cylinder? I had taped everything off when i pulled the intake and headers. i made sure i didn't have any lose debri around when i installed everything.


Only plug that looked bad was #10 when i pulled them all to see and it was black but i believe this is due to i forgot to hook up one coil when i first fired it. none of the plugs look like they have been hitting the piston. look
 
i have ran it aprox 15 mins (to gas station and back then just a few minutes to see if anything changed when i tried different things) and it has 5-40 shell helix oil.
 
71dusterjon said:
i have ran it aprox 15 mins (to gas station and back then just a few minutes to see if anything changed when i tried different things) and it has 5-40 shell helix oil.
ok and I know this is gonna sound stupid, but I sent a engine to russia, had the same sound same prob
but let me ask a couple first
oil pressure?
idel, and at rpm
and how long was it sitting?
 
oil pressure was normal. i believe like 70-75. never goes below that.
idle sits about 750 and when i did drive to get gas i never went above 3000.
probably was sitting for a good month. half the tank is fuel from a month ago the other half is fresh. plus about an ounce or so of that lucas fuel treatment.
 
That sounds like exhaust noise. It seems too slow for it to be something hitting a piston (the exhaust stroke only happens every 2 revolutions, so exhaust sounds are usually slow like that). It is either leaking around your PVC breather where it goes into your exhaust or right at the manifold gasket.

That sound has nothing to do with dentonation/pre-ignition (knock). You either have an exhaust leak or a valve train issue. I'd bet dollars to doughnuts that it is exhaust.
 
71dusterjon said:
oil pressure was normal. i believe like 70-75. never goes below that.
idle sits about 750 and when i did drive to get gas i never went above 3000.
probably was sitting for a good month. half the tank is fuel from a month ago the other half is fresh. plus about an ounce or so of that lucas fuel treatment.
ok then lets look at this rational
1. it has to be a rotating assembly to make the noise
2. it increases with rpms

so what rotates? crank , rods, pistons, flywheel, cam (short version)

I thought you built the engine thats why I mention rod bearings

but your bearings should be fine, they were not changed, so should the pistons
nothing found on top of pistons or one of the electrodes should show it
timing chaing and oil pump should be fine
nothing found in top end, springs , pushrods
so what does that leave?
go back to what you did.
intake headers and such

pretty sure you didnt drop anything so you should be good there.

so what do ya have left, lifters, possible empty lifters,
the one I sent to russia had sat for two months, lifters bleed down, he called same noise, ran it for about an hour or so , noise gone, sounds stupid , but its been a couple months and still fine

only other thing I can think of would be in the clutch area, but nothing that would sound like that.
could actually be one lifter not wanting to pump up and that could also be why it sounds like its not hitting all ten also

forget the bearings you didnt touch them.
top end good, plugs good, gas want do it.

I cant tell ya to crank it and let it idle for obvious reasons, but I prob would do that on mine;)

now you can as it is running , pull one plug wire at a time , see if the noise or engine sound changes at all, that will give you a estimation of which cylinder it is
 
You could go get a mechanic's stethoscope and pin point the problem.
 
you guys are very comforting. honestly. i had my doubt but you guys sure made them go away. i have one at my shop that i'll get tomorrow and see where its coming from.

I'll check all the gaskets to make sure i haven't missed anything and if all checks out good i'll pretend i'm tony and run my motor for a while.
 
71dusterjon said:
you guys are very comforting. honestly. i had my doubt but you guys sure made them go away. i have one at my shop that i'll get tomorrow and see where its coming from.

I'll check all the gaskets to make sure i haven't missed anything and if all checks out good i'll pretend i'm tony and run my motor for a while.
I know some are saying that is just nutts, but I checked the one I sent out, checked out all the bearings and stuff, so I knew they had to be good,, only thing I could thing of is these dang quick bleed lifters we got, so I took a chance , told him to idle it for awhile, it worked out , so if you find a lifter bad, I even have one here that someone ordered and never paid for ;)
 
Dude If you can't find the problem by pulling wires. Go to the parts house and buy a stethoscope 10 bucks you can really pinpoint the problem
 
i got a scope which ill use tomorrow along with pulling wires. called it quits tonight before i got really mad and something else happened.

how hard is it to change lifters on these bad boys? also how will i distinguish between ex and in lifters if i do find one cylinder to be the problem.
 
71dusterjon said:
i got a scope which ill use tomorrow along with pulling wires. called it quits tonight before i got really mad and something else happened.

how hard is it to change lifters on these bad boys? also how will i distinguish between ex and in lifters if i do find one cylinder to be the problem.
replace both
 
71dusterjon said:
can i remove valve covers and run engine at idle to see how the valve train it running and see if its a lifter?
you can , but have a good fire extinguisher around and a hose pipe in case the oil catches fire on the manifolds. jsut be careful;)
 

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