440 vibration - help?

[DPL]

Hi everyone,

Here's my issue, if anyone has advice, I'd really appreciate it.  I have a vibration in my car and I am fairly certain it is engine vibration. 

The 440 I have was supposed to be rebuilt by the guy I bought it from.  It sure runs tight and strong.

I was told by the guy it had a hemi crank. 

I just swapped out the harmonic balancer with another to see if that got rid of the vibration - no go.

Will a hemi crank install into a 440?  Will the motor still be externally balanced?

[JB400]

Is the vibration while the car is sitting still or while it's moving?

Any funny noises?

[DPL]

Sitting or moving.  No noises.  Just a vibration.

I just ran the motor without a damper and the vibration is half as bad. 

[JB400]

Did you check to see if your counter weights are still intact on your torque converter?



If it isn't the torque converter, and it isn't the harmonic balancer,  you'll have to pull the pan

[DPL]

4 speed car.  Tried three different balancers.

Would a neutral damper have the same effect as not running any damper at all?

[A383Wing]

wrong flywheel comes to mind first

[ws23rt]

If the guy that rebuilt it did not do a crank balance (internal balance) Than that could be it. If he did than vib damper and flywheel should be the non weighted type

[Cooter]

IIRC, SOME hemi engines (426 style) had a specific balancer. Hemi only. If the engine was a cast crank 440 and he just dumped in a "Hemi" crank, did not rebalance the bottom end, or left the Cast crank Flex plate on the torque converter, then you are chasing your tail.

I know of at least 5 different balancers for the Big Block Chrysler including the Hemi.

[skip68]

Motor or tranny mount?  Check the passenger side motor mount.  See if you can use a pipe/bar and lift the motor.   They tend to break.      Ive broke two before I did the bolt trick from Firefighter Ron.   

[DPL]

Thanks for the input everyone.  I'll check the mounts and failing that, drop the pan and figure out what crank I have.

[skip68]

Well?   Any update?   

[DPL]

I've been living with this vibration because the car is too cool not to drive.

Finally got it on the hoist.  Its definitely an 8 bolt forged crank.  I run the numbers on the web and nothing comes up.

I finally decided to get at the flywheel.  I see I can bolt on some weight to this one.  Check out the pic.

Anyone have an idea on how much weight I should add to counterbalance?

We're fairly certain this has to be it.

[John_Kunkel]

If the guy that rebuilt it did not do a crank balance (internal balance) Than that could be it. If he did than vib damper and flywheel should be the non weighted type

The Hemi uses a heavier rod/piston than the RB so the mismatch of parts probably contributes to the vibration.

It's unlikely that you can "guess" the proper external balance parts to make it right.

[fy469rtse]

I'd like to see a lot of photo's , engine , the two dampers you have tried, but like john has said , you cant guess the weight , you might get lucky , but the odds dont look good,
typically crank rods pistons damper and flywheel are balanced together at machining stage before engine is assembled,
go back to the guy who built engine, maybe he just knows what 's needed ,
post a photo of harmonic balancer, i would like to see the one your using
cast cranks have a weighted balancer , steel dont , because there internally balanced, you may have the wrong one, balancer and adding to problem,
bolt area on flywheel mainly for cast crank application

[DPL]

I really appreciate the help.  I will try document this better but that will take time.

I took this flywheel in to see if it was balanced.  Guy says its out by an ounce and a half.  I'm wondering it that would cause a very noticeable vibration.  I'll get it balanced and report back.

[DPL]

Had the flywheel trued up, added an ounce of counterbalance weight (my brother is way too handy, he made it for me).

The vibration is half of what it used to be.  It's also a more steady vibration, not oscillating. 

I'm gonna add another ounce.

[A383Wing]

curious, how are you knowing exactly how much to add and exactly where to add the weight?

[ws23rt]

curious, how are you knowing exactly how much to add and exactly where to add the weight?

This is a very good question. It sounds like you are working on just the flywheel?
Is this something you are doing at home?
Have you wondered whether the weight needs to be on the inside or the out side of the flywheel? 
Also adding weight to a flywheel for balance (as opposed to removing it)seems like a risky way to go.

[DPL]

My brother is the master.  I am merely the slave.

I realize that the engine is going to have to come out to be done correctly but my brother thought we'd try a couple of things first. He found info on McLeod flywheels that states 70-70 440 engines require adding 30.1 grams of counterbalance weight while 73-78 cast cranks require 64.5 grams. My flywheel appears to be a copy of the McLeod unit so we replicated this.  We now have 30 grams added and I'd say 70% of the vibration is gone.  Way better, I may just leave it as is.

By the way, the flywheel was only out by a gram and a half from neutral, not an ounce and a half like I mentioned above.

Yes, this is being done in my shop in the backyard.  If you look at the flywheel pic, you will see bolt holes specifically for adding weight.