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440 tapped/knocked, then it disappeared
#1362464
12/31/12 09:06 PM
12/31/12 09:06 PM
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Joined: Dec 2007
Posts: 1,584
MD
p d'ro
OP
pro stock
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OP
pro stock
Joined: Dec 2007
Posts: 1,584
MD
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So my 67 HP 440 motor was recently rebuilt. Mild with CompCam XE262H-10, stock rebuild to 915 heads, 9.5:1 and less then 500 miles. Motor always seems to have almost unnoticeable tic that rises and falls with rpms on drivers side. Thought it was exhaust manifold leak as the bolts keep coming loose. Motor always runs great, especially after getting distributor curved and air/fuel set. Went out today for a flog. Cold out, probably 35 degrees F, and I warmed up car to 160 and drove for about 10 minutes. Then hammered it for one run close to 5 grand and it pulled hard. DId it again from dead stop, shifted and snagged second just below 5k, and a scary heavy tap or low knock from left side of motor. Sounded hurt and I babied it for about 30 seconds to get home. When I stopped to turn it disappeared and did not come back. What? Was it a lifter that just got temporarily jacked, or do I have an issue that should be further investigated? Oil looks brand new and just below full. Temp dead on 165 degrees, no weird smells, etc.. Any ideas???
Happy New Year!!!
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Re: 440 tapped/knocked, then it disappeared
[Re: p d'ro]
#1362465
12/31/12 11:53 PM
12/31/12 11:53 PM
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Joined: Jan 2004
Posts: 27,347
Today? Who Knows?
1_WILD_RT
Management Trainee
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Management Trainee
Joined: Jan 2004
Posts: 27,347
Today? Who Knows?
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I had an engine do something similar once, I was expecting to go into the engine but it ran so good I didn't for 6 years... Didn't use any oil, no smoke nothing.. When I pulled the heads found a chunk of # 7 piston top land had come off & likely went out the exhaust.... KB Hyper Pistons
"The Armies of our ancestors were lucky, in that they were not trailed by a second army of pencil pushers."
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Re: 440 tapped/knocked, then it disappeared
[Re: p d'ro]
#1362470
01/01/13 03:06 AM
01/01/13 03:06 AM
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Joined: Jun 2012
Posts: 1,899
MYRTLE BEACH SOUTH CAROLINA
ek3
top fuel
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top fuel
Joined: Jun 2012
Posts: 1,899
MYRTLE BEACH SOUTH CAROLINA
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Quote:
So my 67 HP 440 motor was recently rebuilt. Mild with CompCam XE262H-10, stock rebuild to 915 heads, 9.5:1 and less then 500 miles. Motor always seems to have almost unnoticeable tic that rises and falls with rpms on drivers side. Thought it was exhaust manifold leak as the bolts keep coming loose. Motor always runs great, especially after getting distributor curved and air/fuel set. Went out today for a flog. Cold out, probably 35 degrees F, and I warmed up car to 160 and drove for about 10 minutes. Then hammered it for one run close to 5 grand and it pulled hard. DId it again from dead stop, shifted and snagged second just below 5k, and a scary heavy tap or low knock from left side of motor. Sounded hurt and I babied it for about 30 seconds to get home. When I stopped to turn it disappeared and did not come back. What? Was it a lifter that just got temporarily jacked, or do I have an issue that should be further investigated? Oil looks brand new and just below full. Temp dead on 165 degrees, no weird smells, etc.. Any ideas???
Happy New Year!!! [/quote  a big mabe. -a wristpin. they can come and go or come and never leave.
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Re: 440 tapped/knocked, then it disappeared
[Re: p d'ro]
#1362471
01/01/13 04:06 AM
01/01/13 04:06 AM
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Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
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Quote:
It is a very faint tiktiktik that increases with engine speed and is heard by valve cover near exhaust manifold.
header ex leaks can sound remarkably identical to lifter inadequate preload/bad lifter. If you're sure the ex is not the culprit then from your last descrip I'd say lifter preload or a bad lifter(s). Can press straight down vertical on the rocker arms when idling with a wooden hammer handle & it will somewhat quiet a bad one so you can ID it. EDIT Press on the lifter end of the rocker arm & this will help you with ID ing a bad lifter but not with ID ing insufficient preload
Last edited by RapidRobert; 01/01/13 12:23 PM.
live every 24 hour block of time like it's your last day on earth
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Re: 440 tapped/knocked, then it disappeared
[Re: p d'ro]
#1362473
01/01/13 11:13 AM
01/01/13 11:13 AM
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Joined: Mar 2010
Posts: 1,880
Out in Left Field, NY
bobs66440
top fuel
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top fuel
Joined: Mar 2010
Posts: 1,880
Out in Left Field, NY
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If it were me I would definitely pull the valve cover and check for anything loose. Wiggle the rocker arms. You will have a little side-to-side movement but you should have no significant up or down movement on the pushrod end (toward center of engine) of the rocker arm. Of course, if it's not making the noise now, you probably won't find anything wrong.
For the tik tik sound, it's very possibly a header leak. They sound identical and it's a very common thing. Maybe try to tighten the header bolts. If they have been loose before, the gasket may have already burnt and tightening won't help.
Or as mentioned it could be a bad lifter or improper lifter preload which is easy to do on these engines if you don't know what you're doing. Unfortunately, there's no simple way of checking it all over. If you are unsure, it's best to take it to a mechanic you trust but is also familiar with these engines.
Technically, one lifter can be changed but, as they told me when I had this problem, you run the almost certain risk of wiping out your cam. Then you have a real mess. Some will tell you they have done it without a problem. I'm going through this right now. I had one lifter go bad after 2000 miles and now I'm in the process of installing a new cam and lifter set because I didn't want to risk it. A real pain for the sake of one $9 lifter.
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Re: 440 tapped/knocked, then it disappeared
[Re: p d'ro]
#1362474
01/01/13 11:24 AM
01/01/13 11:24 AM
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Joined: Jan 2003
Posts: 8,945
Holly/MI
Dean_Kuzluzski
master
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master
Joined: Jan 2003
Posts: 8,945
Holly/MI
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The time when I punched a pushrod through a rocker arm it made a lot of clatter. As I limped home, with good oil pressure, it went away. The pushrod had been pushed just far enough into the rocker where the lifter no longer hit it. A seasoned flat-rate mechanic/friend stopped by a day or two later and I fired it up for him. He thought is sounded fine. This is with a 284/484 cam, kinda lumpy. Pulled a valve cover, two rockers broke, one had the pushrod punched through and the other blew into 2 pieces when the fulcrum split. True story. 
Last edited by Dean_Kuzluzski; 01/01/13 11:27 AM.
R.I.P.- Gary "Coop" Davis 02/09/68-05/13/04
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Re: 440 tapped/knocked, then it disappeared
[Re: p d'ro]
#1362480
01/01/13 03:06 PM
01/01/13 03:06 PM
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Joined: Jan 2003
Posts: 8,945
Holly/MI
Dean_Kuzluzski
master
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master
Joined: Jan 2003
Posts: 8,945
Holly/MI
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Do a compression check. Dry then wet.
Check the cranking vacuum, with ignition disabled, too.
Easy stuff that will give a good clue.
R.I.P.- Gary "Coop" Davis 02/09/68-05/13/04
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Re: 440 tapped/knocked, then it disappeared
[Re: p d'ro]
#1362489
01/02/13 01:23 PM
01/02/13 01:23 PM
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Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
RapidRobert
Circle Track
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Circle Track
Joined: Nov 2003
Posts: 36,041
Lincoln Nebraska
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Myself I would have someone check preload unless it was a significant bang & it sounds like it was which would point to something more severe than the light clatter from preload. If you have 50lbs of oil psi then adding oil will not help it assuming that was it & I doubt it tho an oil gauge can read good but from the convoluted oil path the bearings can still be starved at times which is why oiling mods when going together are beneficial. Bore scopes are nice but pricey & if there was something in the combustion chamber you'd still hear it. After checking preload (if called for) I'd call it good & run it  . 5K ain't excessive IF Piston to valve/Piston to head (quench)/adequate valve spring psi all good? EDIT I reread your OP & I think bad lifter(s)/preload/header leak on the mild tapping & the thud was something more serious/seperate
Last edited by RapidRobert; 01/02/13 01:35 PM.
live every 24 hour block of time like it's your last day on earth
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Re: 440 tapped/knocked, then it disappeared
[Re: Jwilli500]
#1362491
01/02/13 09:31 PM
01/02/13 09:31 PM
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Joined: Feb 2005
Posts: 4,324
Prospect, PA
BSB67
master
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master
Joined: Feb 2005
Posts: 4,324
Prospect, PA
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Quote:
If it's an automatic, check your torque converter bolts.
This is definitely worth a check, especially for the recent louder noise.
Personnally, I don't think its preload, as you would think 16 lifter would be making noise.
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I'd hate to see what the piston/head would look like though.
