Fluid filled damper for ‘78 440

[73 T&C]

Having trouble locating a new or very good user harmonic damper for my 78 440. It has a cast crank and the part number that I found for it was 3839482…. NLA.

Will the newer fluid filled dampers work the same? Does anyone have experience with them in this or a similar application.

I remember as a kid, there was an old man selling a wheel “Balancer” at the local
Glee market. This Balancer consisted of some ball bearings in a circular tube around a flat metal disc that mounted conventionally between the wheel and hub (much like a brake dust disk). I was the volunteer tester for the guy and he had me un-mount the wheel from a hub to which he had attached to an electric motor with speed control. He removed the balancer and spun it on his finger and it sounded for all the world like my sister’s hola hoop. He spun up the remounted wheel he had me bolt back on and and spun the wheel to show it was way out of balance even at slow speed. Off came the wheel and on went the balancer and …. Absolutely no vibration. From the get go… at any speed he set it.

It left a dent in my memory.

Thoughts on the fluid filled damper please???

The reason I pulled it was due to a leak in the cover seal. This one looks to have slipped a bit from pictures I found of the same damper. Damper seal surface was also bent/deformed.

 

[Big_John]

It might be worth having that one rebuilt. I've never used these guys, but have heard of them. Perhaps someone can comment. Chrysler

I've never used a fluid dampener and I'm not really sure if it's going to work correctly with the "external balance" crank. I would give the manufacturer a call and see what they say. Be sure to say "external balanced" when talking to them.

 

[Big_John]

Looks like they have yours in stock and you can probably just exchange yours.

CHR4403 CHR. 440 C.I. 73-78 CAST CRANK ONLY SQUARE RING

 

[CBODY67]

Fluid dampers were first used in full race drag race motors . . . AND were quite pricey. IF they are needed, that price is worth it in those drag racing situations. But quite "not needed" on a stock motor, to me. When balancers "turn" the outer ring usually moves inward or outward, visibly so.

No doubt, your balancer might have a wear ring from the lip seal in the front cover, which is normal. If you did not have the concerns about movement, then you could probably use a "sleeve" for the balancer nose, or find a replacement seal which has the lip moved away from the normal wear ring area, which many aftermarket brands can tend to do.

That "ring of ball bearings" wheel balancer was supposed to be used on wheels/tires which would take a lot of weight to balance (thus, "unbalancable" for normal means, back in the earlier 1960s) or were of very low assembly quality. Our tire dealer talked my Dad into one for a wheel on our old '51 GM pickup. Did not seem to really balance things, but sounded like a lot of ball bearings in a tube as the vehicle slowed to a stop, EACH time. After a few weeks, it was removed.

Enjoy!
CBODY67

 

[Big_John]

Fluid dampers were first used in full race drag race motors . . . AND were quite pricey. IF they are needed, that price is worth it in those drag racing situations. But quite "not needed" on a stock motor, to me. When balancers "turn" the outer ring usually moves inward or outward, visibly so.

No doubt, your balancer might have a wear ring from the lip seal in the front cover, which is normal. If you did not have the concerns about movement, then you could probably use a "sleeve" for the balancer nose, or find a replacement seal which has the lip moved away from the normal wear ring area, which many aftermarket brands can tend to do.

That "ring of ball bearings" wheel balancer was supposed to be used on wheels/tires which would take a lot of weight to balance (thus, "unbalancable" for normal means, back in the earlier 1960s) or were of very low assembly quality. Our tire dealer talked my Dad into one for a wheel on our old '51 GM pickup. Did not seem to really balance things, but sounded like a lot of ball bearings in a tube as the vehicle slowed to a stop, EACH time. After a few weeks, it was removed.

Enjoy!
CBODY67

You really can't compare a harmonic balancer with wheel balance.

The harmonic dampener does a couple things... It helps cut down torsional and resonance vibrations from the crankshaft. The crank twists back and forth as the cylinders fire and that causes the torsional vibration. If you look at a harmonic balancer for an internal balanced engine, by itself, it needs to be dynamically balanced with really no relevance to crank balance. It just cuts the vibration down.

A secondary use on these cast crank cars is to make up for the heavier rods used in these engines. The crank simply does not have enough mass to balance the added weight of the rods. The solution has been to add Mallory metal (really heavy and $$) to the crank to create an internal balanced crankshaft. Honestly, I'm not sure that can be done with the cast crank... But that was the way we would set up the steel crank, heavy rod engines.

The whole thing is a science in itself and I'm just scratching the surface... The liquid filled dampeners do the same, cutting down vibration, but again, they aren't made to compensate for a badly balanced crank. That is that there is no air space in the liquid like a "ring of ball bearings" so the liquid isn't going to move to the light side, like the balls would in one of those cheesy "balancers" that bolt on to an unbalanced wheel.

Of course, an out of balanced wheel and tire causes a vibration too... but no torsional resonance because there's no pistons firing making things twist back and forth.

This is one of the better explanations of how harmonic balancers work. Why you need an aftermarket harmonic balancer

 

[73 T&C]

Looks like they have yours in stock and you can probably just exchange yours.

CHR4403 CHR. 440 C.I. 73-78 CAST CRANK ONLY SQUARE RING

Mine’s a bullet front and it’s a bit pricey.

But, if I can’t figure out something, it’s still a good one.

Thanks!

 

[73 T&C]

You really can't compare a harmonic balancer with wheel balance.

The harmonic dampener does a couple things... It helps cut down torsional and resonance vibrations from the crankshaft. The crank twists back and forth as the cylinders fire and that causes the torsional vibration. If you look at a harmonic balancer for an internal balanced engine, by itself, it needs to be dynamically balanced with really no relevance to crank balance. It just cuts the vibration down.

A secondary use on these cast crank cars is to make up for the heavier rods used in these engines. The crank simply does not have enough mass to balance the added weight of the rods. The solution has been to add Mallory metal (really heavy and $$) to the crank to create an internal balanced crankshaft. Honestly, I'm not sure that can be done with the cast crank... But that was the way we would set up the steel crank, heavy rod engines.

The whole thing is a science in itself and I'm just scratching the surface... The liquid filled dampeners do the same, cutting down vibration, but again, they aren't made to compensate for a badly balanced crank. That is that there is no air space in the liquid like a "ring of ball bearings" so the liquid isn't going to move to the light side, like the balls would in one of those cheesy "balancers" that bolt on to an unbalanced wheel.

Of course, an out of balanced wheel and tire causes a vibration too... but no torsional resonance because there's no pistons firing making things twist back and forth.

This is one of the better explanations of how harmonic balancers work. Why you need an aftermarket harmonic balancer

Great source- thanks.

I spoke with Gerry at “440 Source” (440source.com). He said they had a dimensionally correct unit they make for my application. Correct to have pulleys line up etc…

He also repeated a lot of what you said John.

Unit is 200-1128.

 

[Big_John]

Great source- thanks.

I spoke with Gerry at “440 Source” (440source.com). He said they had a dimensionally correct unit they make for my application. Correct to have pull-ups line up etc…

He also repeated a lot of what you said John.

Unit is 200-1128.

View attachment 580965

That looks like a really good option! The bolt-on part is interesting... I would loc-tite those bolts! LOL

 

[73 T&C]

Fluid dampers were first used in full race drag race motors . . . AND were quite pricey. IF they are needed, that price is worth it in those drag racing situations. But quite "not needed" on a stock motor, to me. When balancers "turn" the outer ring usually moves inward or outward, visibly so.

No doubt, your balancer might have a wear ring from the lip seal in the front cover, which is normal. If you did not have the concerns about movement, then you could probably use a "sleeve" for the balancer nose, or find a replacement seal which has the lip moved away from the normal wear ring area, which many aftermarket brands can tend to do.

That "ring of ball bearings" wheel balancer was supposed to be used on wheels/tires which would take a lot of weight to balance (thus, "unbalancable" for normal means, back in the earlier 1960s) or were of very low assembly quality. Our tire dealer talked my Dad into one for a wheel on our old '51 GM pickup. Did not seem to really balance things, but sounded like a lot of ball bearings in a tube as the vehicle slowed to a stop, EACH time. After a few weeks, it was removed.

Enjoy!
CBODY67

I’m glad I’m not the only one who remembers.

 

[volksworld]

i used the 440 source one...is was off a degree or 2 but i filed a new line in it for tdc and 34 and painted it turquoise...the markings weren't engraved in mine...just maybe laser printed?...there was no trace of them after painting....i had looked into other externally balanced ones from Scat and Jegs but they were on indefinite container ship limbo at the time...even the 440 source one vanished for a while and i was praying they hadn't discontinued it due to problems but it reappeared again

 

[73 T&C]

i used the 440 source one...is was off a degree or 2 but i filed a new line in it for tdc and 34 and painted it turquoise

Interesting. I intend to check it installed. Thanks.

 

[70bigblockdodge]

Likely the timing is off due to the keyway cut in the crank. Big blocks are notorious for being off, usually retarded. Only big block I ever had that was spot on TDC is the 400, now in my Challenger (must have been a Wednesday am crank). A fluid dampener is a ring inside the housing suspended in a viscous fluid (hence the name), usually a version of silicone. The external balance must be on the hub itself not the ring. They have bolt on external weights for this. I have never used one.
If you do find you dampener off. You will have to use the piston stop method since heads are on. Your cam timing will be off by the same amount since the share the keyway. If retarded it is closing the intake valve later reducing your dynamic compression ratio, hurting performance except high rpm, and idle quality. I would check your cam timing if it was not done upon assembly.

 

[commando1]

Great source- thanks.

I spoke with Gerry at “440 Source” (440source.com). He said they had a dimensionally correct unit they make for my application. Correct to have pulleys line up etc…

He also repeated a lot of what you said John.

Unit is 200-1128.

View attachment 580965

I'm going with that option.

 

[fury fan]

Thanks for posting that 440Source retrofit! Good to know that exists. Very much like welding weight onto the flexplate to 'make' an externally-balanced torque converter.

A secondary use on these cast crank cars is to make up for the heavier rods used in these engines. The crank simply does not have enough mass to balance the added weight of the rods.

Are the rods heavier in a cast-crank engine vs the LY rods in the older ones?
My belief on the extra weight on the balancer was due to the cast crank being lighter than the forged steel crank, but that the rods were unchanged in weight.

FWIW:
The 70-71 440 HP engines do use heavier rods from the 6-pack engine, so those forged-crank engines have weight on the balancer due to that.
But that is a different balancer than the cast-crank engines. (69 6-pack did not have the heavier rods, so uses std balancer)

 

[Big_John]

Are the rods heavier in a cast-crank engine vs the LY rods in the older ones?
My belief on the extra weight on the balancer was due to the cast crank being lighter than the forged steel crank, but that the rods were unchanged in weight.

You know... I've never had a cast crank 440 apart, but I was under the impression that they had the wide "6 pack" type rods.

I could be wrong though.... Now I gotta look...

 

[fury fan]

I've never had one of them apart either (nor owned one) so we may both learn something.
Where are they wider? Evidently not at the rod-bearing area as that would mean a 70-71 E86 or E87 would have different crank machining, which would make the crank special too, which I haven't heard of.
Wider in the beam area?

 

[Big_John]

I've never had one of them apart either (nor owned one) so we may both learn something.
Where are they wider? Evidently not at the rod-bearing area as that would mean a 70-71 E86 or E87 would have different crank machining, which would make the crank special too, which I haven't heard of.
Wider in the beam area?

The rods are wider and heavier.

"6 pack" rods. Note how wide is is at the small end versus the 2 pic.

 

[fury fan]

Yes, those are visibly wider.
I wonder why they used those in cast engines. Any insights?

 

[Big_John]

Yes, those are visibly wider.
I wonder why they used those in cast engines. Any insights?

No idea... They started using them in the '70 six pack engines. '69 six pack used the narrower rod.

The idea is they are supposed to be stronger, but every 440 I ever saw with a rod hanging out of it had the big rods. I always thought they were too heavy.

Now I gotta check on the cast crank having the big rods...

 

[fury fan]

Oh. I thought you got that pic of wide rods from a cast-crank.