Harmonic Balancer causing vibrations 427?
Thread Starter
Instructor
Joined: Nov 2011
Posts: 238
Likes: 30
From: Dallas TX
Harmonic Balancer causing vibrations 427?
I have new ignition wires, properly tuned motor, gaps on plugs, dwell, etc
Holding the rpm steady at 2200 plus or minus 200 and the engine vibrates more than it should. I can feel it running down the road in this rpm range too.
Could this be a harmonic balancer problem?
Holding the rpm steady at 2200 plus or minus 200 and the engine vibrates more than it should. I can feel it running down the road in this rpm range too.
Could this be a harmonic balancer problem?
Race Director
Joined: May 2006
Posts: 18,734
Likes: 2,582
Bring the engine to TDC on #1 cylinder and see how close the line on the damper is with the zero mark on the tab. If not close the outer ring has slipped. More likely though I would check the water pump, fan clutch, fan assembly for signs of the pump or clutch wearing out.
Last edited by MelWff; Oct 23, 2013 at 03:38 PM.
Instructor
Joined: Nov 2012
Posts: 219
Likes: 0
From: Irma Northern WI
Since the 427 is an internally balanced engine, it is not likely that the harmonic balancer would cause such an issue. You should probably look for some other cause. Have you done a compression test? Are all of the valves lashed properly? Is the camshaft worn? These are some of the things to examine. good luck.
Safety Car
Joined: Mar 2007
Posts: 3,652
Likes: 49
From: Bridgewater nj
Since the 427 is an internally balanced engine, it is not likely that the harmonic balancer would cause such an issue. You should probably look for some other cause. Have you done a compression test? Are all of the valves lashed properly? Is the camshaft worn? These are some of the things to examine. good luck.
my 427 went out exactly that way!
Pull the spark plug wires one at a time and see which one doesn't make a difference. Then pull the valve cover to watch the rocker arms on that cylinder or cylinders... i had 3 compromised cylinders. You can see that they aren't moving as much as the others when you look closely. I went crazy for almost a week before I noticed the rockers. This was before the word got out about the oil going to crap!
Compression test will not show any problems because the valve is still opening a little.
Last edited by hugie82; Oct 24, 2013 at 10:48 AM.
