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harmonic balancer

11K views 17 replies 8 participants last post by  J10Diesel 
#1 ·
has anyone tried to put one of these on an engine that didnt have one?the ones that are installed below the crank inside the pan.They look like theyd be expensive.ive got a 6bt balancer on the crank,but was wanting more.
 
#2 · (Edited)
I'm planning on putting a Fluidampr on my 4BT. There over $400, but supposed to make the motor last and smooth and more power. Using the stock motor mounts so I fig I'll save on not having to buy Lord's. Gettin cool up thar in NE Oh? pat

That's an external balancer that I'm using, by the way. No expereince with internal one's.
 
#3 ·
Harmonic Dampers

The Cummins service manual states that "the Cummins harmonic damper is reccomended for all 'B' series engines." They reccomend the fluid filled damper for engines running over 2500 rpm. There are also several aftermarket dampers out there.
I am running a Fluidampr and it works for me.
 
#4 ·
#6 ·
I'm going to install a Fluidamper on mine, to cut down on vibration transmitted to the frame. They do work and several here have used them successfully.

They are a bit expensive $400. but you could probably find one off a 6BT in a junk yard for cheap. It's just a viscous damper and doesn't know if it is on a 4 or a 6

On mine I have to find a smaller pulley to drive the A/C compressor as the rim of the Fluidamper is so big in interfers with the vee belt overlay pulley. I also have to drill and ream a dowel pin hole in the crank to drive the damper.

I believe the inside the crankcase engine balancers are designed to be used on stationary engines running at constant speeds such as generators, and are designed around certain speeds. They bolt onto the block as a unit (girdle) on top of the mainbearing caps and are geared and timed to the crank. I don't think they are designed to work on "swing load" or automotive type applications.

Most of the Boat motors I have seen have crank mounted dampers. Which I was told were originally sourced from Fluidamper. Now China.

Randy
 

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#8 · (Edited)
I have a 6bt fluidamper im not talking about that type though.Im talking about the geared balancer that is run off of the crank gear.Its not standard on most 4bts.It is in my cummins shop manual for b series engines ,on page 0-31.Is this what you guys call the fluid dampener?the gear runs 2 cams with weights to counteract the throw of the piston to decrease torsional load
 
#9 ·
Similar setup in my 2.0t Audi it sounds like which I removed.

DSM guys junk them as well. They tend to let go at high revs and hurt performance.

understandable from a comfort point of view I guess in these motors, just doesn't seem worth it to me.
 
#14 ·
The internal balancers cause oil turbulence which causes frction and cuts HP. As stated above that doesn't matter on stationary engines as much because they can be optimised for certain RPM levels.

High HP guys run dry sumps because oil drag is inefficient. Also, engineers try things on the public to see how they go and I suspect that internal damping may be one one a' dem thangs. Stick with an external damper - Fluidampr seems to be the best and a good tune and forgetaboutit. That's what I'm doin.:)
 
#15 ·
Types of Harmonic Dampers

There are two types of harmonic dampers. The first is a damper with a rubber insert. Over time the rubber hardens and can slip out of alignment causing the damper to fail.
The second type is filled with a fluid and is sealed. Cummins has a fluid damper and there are several aftermarket manufactures.
The problem I have with trying to tell someone how well a given damper works is that I cannot express vibration as a quanity ( as 12 volts or 125 PSI ).
In my case I looked at several dampers and bought one. I can say that it reduced my vibration from idle to 2500 rpm. I don't sell dampers and I am not an engineer.
I did a lot of research before I bought my damper. I selected one that works for me.
 
#17 ·
Which Damper



I bought the 1st generation Fluidampr. It has reduced my vibration over my entire rpm range.

Thanks for the vibration defination.

J10diesel
 
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