New Dorman balancers

[crash2win64]

The balancer doesnt just absorb shock it prevents the shocks from happening.

Fluid has a wonderful property in that it maintains its momentum to oppose the force of the changing momentum. You have two choices, spend $5K to rebuild and balance the whole rotating assembly and not have your truck for a couple weeks, or get a $500 fluidampr.

$5000 to rebuild and balance the motor!!!????? I hope your not serious...

The fluidampr will absorb harmonics and so will a regular harmonic balancer and for a cheaper cost than that hyped up fluidampr. Yes the stock ones were crap but that doesn't mean every regular style harmonic dampener is.... Also putting a fluidampr on does not mean your balancing anything. The price of balancing a rotating assembly here as of two days ago was $175..... Rebuilding the motor by my account will be in the $2-3k range...

 

[Matt Bachand]

Rubber also acts totally different warm vs cold, probably more so than the fluidampr.

Not having to worry about the rubber failing, separating, or expiring is also a huge plus.

I replaced my crankpulley last year and the rubber was not mated properly from factory. What if this was a defective HB? I might not have engine now.

Everything is made so cheap nowadays, that I don't mind spending a little extra money for something that will outlast the truck, and for as critical a part as it is, really has a low chance to fail, assuming its properly built. If its out of wack, i'm sure you'd know it instantly upon startup.

It also looks badass.

Made in the USA!:thumbsup:

 

[crash2win64]

Your engine still gets balanced with the stock damper though, which itself is a balanced assembly. Then removed, and install a fluidampr, which itself once again is a balanced assembly..

??

Nothing is balanced from the factory. It's set within certain tolerances from the factory but balanced it's not. When you get your rotating assembly balanced you take the harmonic balancer in with all of the rest of the parts. So if you change out the dampener from the one you had the rotating assembly balanced with your changing the balance effectively more or less. A fluidampr will not balance the assembly...

 

[Matt Bachand]

I take interest in your opinions about fluidampr. I'm due for a replacement HB soon thats why.

I'm not sure this conversation is about balancing the engine as much as it is about the harmonic balancer.

I think you brought up the entire balancing act

 

[buddy]

Unless youre doing all your own labor how much does it cost to pull, rebuild and install an engine? Labor rate around here is $95 and hour.

You are not supposed to balance the assembly with a fluidampr on, any shop that tried was wrong. Balancing a rotating mass is one thing, and then start blowing stuff up inside the cylinders and you arent in a perfect world anymore. Your balanced mass cant compensate for slight compression or injector imbalance or shocks from fuel rate changes.

 

[THEFERMANATOR]

Nothing is balanced from the factory. It's set within certain tolerances from the factory but balanced it's not. When you get your rotating assembly balanced you take the harmonic balancer in with all of the rest of the parts. So if you change out the dampener from the one you had the rotating assembly balanced with your changing the balance effectively more or less. A fluidampr will not balance the assembly...

ALL factory engines are balanced, otherwise they would all shake like a paint mixer. The factory just specs out a tolerance for each part to weigh and casts them in this way to obtain a certain balance. When you're building so many there is no feasible way to balance evry rotating assembly individually, but this isn't required if the parts are all within a certain spec from the get go. This is why the 305 and 350 use the same castings for cranks, but they do not interchange because they are balanced to a different flyweight spec from the factory. As far as balancers go, the FLUIDAMPER is a VERY good investment but overkill for the majority of engines. Also I still do not understand why FLUIDAMPER doesn't sell the 6.2/6.5 model as a STREETDAMPER as virtually no one who has a 6.2/6.5 requires a SFI spec part. So why do we pay almost double for it?

And yes every engine regrdless of design, balance, miles or fuel will have harmonics in it. The harmonics are caused prominetly by the starting and stopping and changing directions of the rods on every stroke. If you ever watch an engine rotate with oil pan off you will notice that the rods are constantly speeding up and slowing down as well as stopping twice for EVERY revolution of the crankshaft. These constant starting and stoppings act like a hammer as the piston and rod speed speeds up then rapidly stops and repeats. The factory uses a rubber insert between 2 steel shells as it is cheap and is known to last for a reasoneable service life. The rubber works by stoping the ringing of a bell basically which dampens those vibrations from the constant starting and stopping. Fluid balncers are used in certain applications as it is required in them mostly for severe duty commercial applications where longevity is key. Fluid is a superior dampner in every regard as compared to an elastomer balancer assembly. Also they aren't plagued with the slipping problem that elastomer balncers have as the only thing that holds those 2 shells together is the rubber elastomer wedged in between them.

What type of balancer you use has ZERO effect whatsoever on the balance of an engine, and to say that running a fluid type balancer eliminates the need for balancing is foolish at best. The fluid plays absolutely no part in the balncing of the engine which allows the engine to run smoothly and to stay centered in the bearing assemblies. If a crank is out of balance it will cause an engine to have so much centrigifigal outward force that it will grind against the bearing despite the pressurized oil that is present there to cushion and cool the bearings and rotating parts. Also it can lead to NUMEROUS other problems in a vehicle all of which WILL shorten the service life of the engine and vehicle. Provided that no major changes have been made to the rotating assembly, there is really no need to rebalance an engine during a rebuild.

Also you CANNOT balance an engine with a fluid type balancer. You must use a fixed type of solid balancer when balancing an engine if it is externally balanced as the fluid will move and try to dampen the out of balance and skew the balancing process. Fluyid type balacers are balanced before they are filled with the viscous fluid that is used in them. All of my info has been learned from my years of turning wrenches, working in a shop, and building race engines since before I could walk. I don't do many engines anymore, but the ones I do are known to RUN nicely):h.

 

[TurboTahoe]

Yowsa Fermanator, nice post. Well put.

-Rob

 

[3500GMC]

I do know the Fluidampr I have is about DOUBLE the weight of a stocker... The chamber for the fluid is huge. I would certainly think it would dampen much better over a wider range of harmonics and RPM. FYI the spacer that takes the place of the crank sensor is 18MM thick. Or .709". The Fluidampr was made for all the 6.2/6.5 elec/mech variants.

 

[Matt Bachand]

This thread makes me want one even more now.

 

[Dave Barbieri]

ALL factory engines are balanced, otherwise they would all shake like a paint mixer. The factory just specs out a tolerance for each part to weigh and casts them in this way to obtain a certain balance. <snip>

Outstanding job, Ferm! :thumbsup: :thumbsup: :thumbsup:

I've been twisting wrenches and building engines (big and small) for over three decades. Your comments are spot-on.

Provided that no major changes have been made to the rotating assembly, there is really no need to rebalance an engine during a rebuild.

Actually, I pay the extra $$$ to get my stuff balanced within 4 grams. Typical cost is around $225 here in the Tyler area. My machinist will take it down to a 0 gram balance, but the cost more than doubles. Considering the rpm range and the (relatively) light duty usage, I've never seen the need to do that.

For street use, I've built Chevy, Ford and Veedub motors. On average, they've come from the factory balanced within 10 - 12 grams. I've always felt that the $$$ spent on closer balancing specs are more than paid back with increased fuel economy and increased engine life.

Also you CANNOT balance an engine with a fluid type balancer. You must use a fixed type of solid balancer when balancing an engine if it is externally balanced as the fluid will move and try to dampen the out of balance and skew the balancing process. Fluid type balancers are balanced before they are filled with the viscous fluid that is used in them.

Matter of fact, this has been made pretty clear from the get-go: Balance the engine first with the stock HD, then install the Fluid Dampener.

All of my info has been learned from my years of turning wrenches, working in a shop, and building race engines since before I could walk. I don't do many engines anymore, but the ones I do are known to RUN nicely):h.

X2 No race engines, just a long list of streetable motors that run really well and live a long and happy life.

 

[buddy]

The important part is that you are balancing all the parts to a certain weight, so that the bob weight and crank counterweights are all as close to eachother as possible. The balancer on the end of it can be changed with another balanced balancer.

 

[WarWagon]

If you are on a budget like most 6.5 owners get the damper and the pulley from the dealer. The Dorman appears to be junk per other posts showing blown rubber in few miles.

If you have the funds for the high end damper then you can forget about inspecting it often...

 

[daustin]

The Dorman balancer / pulley is a china mfg POS, bought one for my '93 and it lasted 4 months before spewing out rubber out. Got a ACDelco and it's been fine for 2 1/2 years.
Don

 

[BigBlue]

The Dorman balancer / pulley is a china mfg POS, bought one for my '93 and it lasted 4 months before spewing out rubber out. Got a ACDelco and it's been fine for 2 1/2 years.
Don

I fully agree on the Dorman chinese balancer being POS!

my initial impression of that junk was here:
http://www.thetruckstop.us/forum/showthread.php?t=13003

Now after 7000 miles on it, I pulled it out and the rubber was totally cracked
up and chunks were missing:cussing:
It looked worse than the original after 90k miles.

No more! In went a fluidampr and now I can already feel it run smoother
just with my a$$ on the drivers seat

 

[guybb3]

Ones the HB, and ones the crank pulley?

What Matt said!

 

[NVW]

The Chinese can't make rubber, I've bought cheap tape measures and one tire made in China. They all smell like raw rubber, really stinks and doesn't take abuse. God help us if they get a contract with "Trojan".):h

 

[Matt Bachand]

The Chinese can't make rubber, I've bought cheap tape measures and one tire made in China. They all smell like raw rubber, really stinks and doesn't take abuse. God help us if they get a contract with "Trojan".):h

x2, especially judging by their population!!! LOL...

 

[matuva]

Post #1 is a balancer. Post #5 is a crank pulley (attaches to the balancer).

Two different parts.

X2, and you need the 2.

The balancer is first, it is for "balancing" the cranck and the engine.

The cranck pulley has 6 grooves, it doesn't balance anything. It bolts on the balancer and is here for moving the serpentine belt, which itself then moves all accessories : alternator, A/C comp, waterpump, etc...

I had to use some Dorman. Some last, some fail almost quick, not all dorman are equals.
ACDelco looks more trustable...

 

[buddy]

They are kind of both balancers, one is called main/primary and the pulley is the secondary.

Do shops put the pulley on too when balancing? Or if its all balanced its balanced and as long as you put a balanced balancer on its all good.

 

[Matt Bachand]

The crank pulley has the rubber to absorb the jolts in the accessories, Apparently the older 6.2 would violantly slap the belt around without the dampening of the crank pulley.

Good question Buddy, and I see where you're going.. Good point. It does add weight directly to the rotating mass.