440 Vibration at 2500+ rpm

[1963JAM]

I'm chasing down a rythmic vibration. Had tires road surface balanced, which got rid of a lot of vibration at highway speed. But then noticed car vibrates in park revving engine above 2500 rpm. I researched harmonic balancers and believe engine has correct balancer for year. Is there something I should look for at the flywheel or torque converter?

 

[moes]

how's your motor and transmission mounts?

 

[1963JAM]

how's your motor and transmission mounts?

I'll take a look. Didn't think of that. Thanks

 

[1963JAM]

how's your motor and transmission mounts?

Have to wonder if bad engine/trans mounts would make a constant vibration? What I have is a vibration that comes and goes with a rhythm.

 

[zyzzyx]

How long have you owned it, what do you know about the engine, and what was the last thing you did
to it before it started?

 

[AR67GTX]

Dropping all the accessory belts for a short driveway test of reving the engine is also a good idea to elemental any possibility with a bad accessory pulley or similar. Have you had any transmission work done in recent time? New torque converter?

 

[Jeff_383]

Had a vibe at ~2400 rpm in Park, drive, etc... 2 motors, wheels, gears, brakes, exhaust, you name it. Turned out water pump or crank pulley was out of balance. By chance changed them (not to chase vibe, for other reason). Know what, smooth as could be now. So look everywhere, can be the strangest things.

 

[Dave6T4]

Wiggle your fan blade to see if there is movement in shaft. I had a vibration at about same speed in my 440 67 R/T, and found my water pump was pooched, although I had no coolant leak. New water pump fixed it.

 

[Richard Cranium]

 

[cr8crshr]

Also it could be as you stated a Harmonic imbalance which also could be caused by a drive shaft also being out of balance. I'd check that also...cr8crshr/Bill

 

[Dave6T4]

Also it could be as you stated a Harmonic imbalance which also could be caused by a drive shaft also being out of balance. I'd check that also...cr8crshr/Bill

Mine had the vibration at the same engine speed whether it was in First, Second, or Drive. I figured that ruled out the drive shaft.

 

[RemCharger]

Rules it out when the op says it's in park.

Need to know the crank type, then see if the front/rear balancing is correct.
I've had a cast crank with internal balancer and no TC weights.. put it right and it was good.

 

[1963JAM]

Purchased car as is this summer. Previous owner didn’t do any work on car except to remove thermostat to solve overheating issue (old school). I have no info on who put this 440 in a 318 car with later year exhaust manifolds and electronic ignition and no fan shroud. So I’m chasing the missing puzzle pieces to make this rag top a dependable cruiser. You all gave me some great ideas to check for the bad vibe. My worst fear is internal balance issue. Will say the vibration isn’t serious but noticeable knowing it’s there.

 

[1963JAM]

How long have you owned it, what do you know about the engine, and what was the last thing you did
to it before it started?

Haven’t done anything to engine or drivetrain. Bought car as is this past August, thought vibration was tire balance. Now I’m on the hunt.

 

[1963JAM]

Dropping all the accessory belts for a short driveway test of reving the engine is also a good idea to elemental any possibility with a bad accessory pulley or similar. Have you had any transmission work done in recent time? New torque converter?

No tranny work.

 

[1963JAM]

No, mediocre vibration.

 

[RemCharger]

Need to look at the tc ,see if chunks of weight are welded on it

 

[zyzzyx]

It's rough when someone else could have done something! Try all the obvious stuff and then
if you don't come up with any answers the only thing you can do is tear down the engine.
I know, it's not what you wanted to hear, but mixing and matching parts leads to problems
if the last owner didn't know what they were doing. Mismatches between balancer/crankshaft,
torque convertor/crankshaft, internal parts/pistons changed. If the vibration is there while
NOT in gear, then it is in the rotating assembly of the engine. Not the trans or drive shaft.

 

[WileERobby]

Well, actually it "could" be the trans torque converter. With ALL accys/belts off, engine mounts confirmed good and tight, a vibration would be between the vibration damper and the torque converter. I'd check those two definitely before going into the engine. Change the damper, check the flex plate and the converter for cracks, loose bolts, etc.

 

[zyzzyx]

Well, yes, The rotating assembly IS also the torque convertor! It's bolted to it! But that's where it stops. Change the
damper to what?