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Fluidampr...IMHO Waste of Money

I can't change the title. Just didn't think it was worth the money. I don't race my engine and a stock quality balancer does the job just fine. finding a quality one may become the issue though/. As GW pointed out, if they didn't rate it SFI it could probably be had cheaper.

If you decide you'd like it changed Kenny, it is solely up to you. Let myself or one the other mods know and we'll get it done for you, if you choose to go that route...
 
Maybe it did not post and he thought it got deleted. That has happened to me a few times. I made posts , it looked like the post went though, then I could not find it later.
 
Not that I let it alter my decision when I bought my FD but AFAIK Scat will not warranty any crank that a FD is used on. I have heard stories both ways of why.
 
Im with buddy on this one. Not talking money, that aside. Does it do a better job? I personaly would only be guessing, but only from what I have read and heard other members state. The stock HB is tuned to a narrow frequency where as the Fluid Damper is caplable of more. I know that may not be a scientific answer but....
I also think of it and relate it to an unbalanced tire. You feel the vibration only at one speed, but once you drive through it it smooths out again That would be like a stock HB. Where as the Fluid Damper would be capable of balancing through a broader range.
What do ya'll think?

Edit: Most Dorman is junk. Most anything from China is junk.
 
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If you decide you'd like it changed Kenny, it is solely up to you. Let myself or one the other mods know and we'll get it done for you, if you choose to go that route...

Sure, make it something less offensive. I have a natural way off pssing people off, it's a gift...:rof:
 
Crap I'm supposed to rebuilding an engine for a client right now as well as go do some work on a 3208 and here I am making keystrokes instead!:D
 
Or is the use of a cast crank a crap shoot from the start.
That can be said for any part,nothing is completely fool proof.
Some people have no problems at all,others have no problems but.
Often something is the weakest link,upgrade that and you'll find the next weakest link etc till you come full circle ;)

BTW todays aftermarket upgrades or replacements are often worse than the original.:rolleyes5:

Every body blames China,i blame the US(or Canadian) counterparts that does the ordering there and sets the specs and quality.
 
Or is the use of a cast crank a crap shoot from the start.

If GM's bean counters didn't get in the way these engines would've had forged steel cranks like the designers at Detroit Had originally come up with for the 6.2(so i'd figure the 6.5 would've gotten them as well). When GM's bean counters axed the forged steel crank due to cost and replaced it with the cast nodular iron crank, the folks at Detroit guaranteed crank failures. They were right.

I hate GMs bean counters.

Chinese stuff is all crap. Period. And the parts coming from GM made there show it. I bought a tranny mount for my Burb from Advance, name brand and it was made in china and half the weight of the original and looks cheesy. I have yet to see any quality part come from there a . I am older and been wrenching a long time and the quality of replacement part as of the last 5 years in particular is just disgusting. It makes you want to throw up your hands and say, "Why Bother ?". My CUCV was another recent example when I could not get a quality new heater core for a box style chevy. Damn 10 yrs ago parts for those truck were hanging on the wall in 7-11. I had to pull out the Chinese made piece of garbage and have the original one repaired. Truck has awesome heat now. Many many more examples. The Dorman stuff is junk and there are many many failure stories. Look at Dave's throw out bearing/clutch story. Same with starters and Alternators. Now you can't even go to a local re builder anymore cause even if the rebuild in house, the parts are crap. For the Mechanical Enthusiast, these indeed are dark times.

Don't even get me started Kenny. I go out of my way to avoid things made in china when it comes to the trucks. I don't give a damn who's responsible for the part being made in china, the quality of the parts suck. They are made by some chinaman, possibly even a child, that doesn't give a damn, and probably doesn't even know what the part is for. I've always said you can't get something for nothing. It's made in China for a reason and that reason is either cheaper labor or cheaper parts, but it's usually a bit of both.

Look at anything made in America from times past and see how long it lasted compared to anything made overseas, regardless of what it is. Hell look at my 1940s shop compressor. The Delco electric motor built in Dayton, Ohio has run it's heart out for over 60 years, and it still runs like new, even with the original oil bath bearings in it.
 
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One of the issues I had , when rebuilding my 6.2 , was the fact that you have to have another balancer to balance the crank , rods , etc before you use the FD . Directions state that you can not balance with the FD .

HAs to due with the construction and how the rotating assembly is dynamically balanced on the machine. The inner ring on teh stock damper is a counter weight. Fluidampr has a balance weight in it (supposedly). but the "gel" and the outer ring are supposed to mess up this balancing scheme by being "too effective". I've always questioned that one; that explanation has a few flaws that don't ring quite true to me....

Also , my question is that if you balance to better than production standards , do you need the FD or is the factory unit better able to handle tighter tolerances ?

Ah yes, "blueprinting"...wonderfull process and I recommend it to anyone with the time, skill or money to do it. But, more relevant to the subject;

The factory balancer and fluidampr serve two functions. On an externally balanced engine, the balancer is a counterweight, much like the crank internal counterweights. the rubber in the factory damper and the gel in the fluidampr are a type of "shock absorber". It allows the internal ring to move ahead of the outer ring when the power pulse hits. the outer ring lags behind and then catches up as the rubber/gel pulls it along. This smoothes out the forces acting ont the crank across it's entire length.

Problem is, on an externally balanced engine you can't get enough counterbalance int eh crank weights to be effective enough. It also has to do with orders of vibration and how you compensate for them. So you need an external counter weight and a scheme to deal with the other inbalances that come with internal combustion.

It's a bit hard to describe in a nutshell, but there's my best shot at it....

So , buy a new factory unit and have the machine shop balance and then use the FD ? My crank needed some " heavy " metal and hopfully this will let the factory balancer do it's job .

That would work fine, so would a just a new balancer.

The real question with a new balancer is;

How much do you trust it?

Should be no problem for most quality units for at least 100,000 if not two or three times that amount of miles.

Actually, in 30 odd years of dealing with externally balanced engines, the 6.5 is the first time I've run across the damper being a problem to the extent where it snaps a crank.

99% of the time, the old balancer goes back on with no real worries. We only used to install non-elatomeric style dampers (there's more than "fluidampr" on the market, just not for 6.5's) on gassers when someone wanted them or it was a special purpose build.

Of course, In relative terms, diesels are new to me so maybe there's more snapped cranks and bad dampers out there rusting in the weeds..

I completely undertand how hard it is to choke down a 400 dollar bill for something as un-glamorous as a dampr.

I spent the money for peace of mind that this old 6.5 isn't going to chuck a bit of rubber and send things foolish before I catch it going south.

Ya makes ya choise, then ya pays ya money.....
 
Every body blames China,i blame the US(or Canadian) counterparts that does the ordering there and sets the specs and quality.

Ding ding ding. We bash china like it's 'cool' but what we really mean is: The white collar CEO has deemed it necessary to sell us (the blue collar poor SOB) out to china and abroad for pennies on the dollar. And they don't lose any sleep at all.

It's all about the bottom line.

Consumerist America is none the wiser.

Read the very bottom line of my signature.

I just knew this thread would become political...:D
 
HAs to due with the construction and how the rotating assembly is dynamically balanced on the machine. The inner ring on teh stock damper is a counter weight. Fluidampr has a balance weight in it (supposedly). but the "gel" and the outer ring are supposed to mess up this balancing scheme by being "too effective". I've always questioned that one; that explanation has a few flaws that don't ring quite true to me....



Ah yes, "blueprinting"...wonderfull process and I recommend it to anyone with the time, skill or money to do it. But, more relevant to the subject;

The factory balancer and fluidampr serve two functions. On an externally balanced engine, the balancer is a counterweight, much like the crank internal counterweights. the rubber in the factory damper and the gel in the fluidampr are a type of "shock absorber". It allows the internal ring to move ahead of the outer ring when the power pulse hits. the outer ring lags behind and then catches up as the rubber/gel pulls it along. This smoothes out the forces acting ont the crank across it's entire length.

Problem is, on an externally balanced engine you can't get enough counterbalance int eh crank weights to be effective enough. It also has to do with orders of vibration and how you compensate for them. So you need an external counter weight and a scheme to deal with the other inbalances that come with internal combustion.

It's a bit hard to describe in a nutshell, but there's my best shot at it....



That would work fine, so would a just a new balancer.

The real question with a new balancer is;

How much do you trust it?

Should be no problem for most quality units for at least 100,000 if not two or three times that amount of miles.

Actually, in 30 odd years of dealing with externally balanced engines, the 6.5 is the first time I've run across the damper being a problem to the extent where it snaps a crank. 99% of the time, the old balancer goes back on with no real worries. We only used to install non-elatomeric style dampers (there's more than "fluidampr" on the market, just not for 6.5's) on gassers when someone wanted them or it was a special purpose build.

Of course, In relative terms, diesels are new to me so maybe there's more snapped cranks and bad dampers out there rusting in the weeds..

I completely undertand how hard it is to choke down a 400 dollar bill for something as un-glamorous as a dampr.

I spent the money for peace of mind that this old 6.5 isn't going to chuck a bit of rubber and send things foolish before I catch it going south.

Ya makes ya choise, then ya pays ya money.....

You got any scientific proof to back that up! these 6.5 cranks and others are known to have broken with and without a perfect damper pulley.
And not all 6.5 cranks break as a result if the damper happens to crater either.
IMO It depends a lot on how an individual uses or abuses an engine
 
You got any scientific proof to back that up! these 6.5 cranks and others are known to have broken with and without a perfect damper pulley.
And not all 6.5 cranks break as a result if the damper happens to crater either.
IMO It depends a lot on how an individual uses or abuses an engine

Ok, let me change that for you then;

Instead of "run across" you can replace that with "heard of".

In the 25-30 odd years of working on engines, the only other snapped crank I've personally seen is on an old chrysler 2.2 I fixed for my Dad.

Only shattered cranks I've seen in 6.5's are the ones the local yards have tossed as scrap.

But you are right in one aspect, cranks break for many reasons; casting imprefections, imbalances, assembly error, life cycle fatiguing, etc...
 
Well, I have one in my driveway that broke the crank from the damper but I will blame the previous owner. It was apparently making noise for some time and he ignored it.
 
You know I wonder if a benefit of a Fluidampr would solve the 5th gear nut loosening due to Vibration/diesel harmonics on NV4500 equipped trucks ? I smell an experiment in the works...
 
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