Rookie balancer mistake

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clementine

clementine

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Many mistakes here.
Balancer on this engine that came with the car looked like crap and one bolt didn't line up. Read the forum to see recommended. Ended up buying a nice one. Fluidamper 720311

So here goes....
Didn't measure snout.
Didnt read the instructions.
I took down a couple burrs on keyway but didn't measure.
Installed fairly well by using a stud and nut to draw it on.
Was going well until it wasn't realizing i hadn't measured and the progress was feeling like i was damaging ****.

I did.

So there is galling. But the key seems like the correct size, but the distance from face of crank down in the hole is about 0.100 less than snout on new damper. I lightly touched up both surfaces with emory although i didn't try too hard to remove grooves as i thought i should ask for advice.

Thanks FABO!


Took some pictures

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Fluidampers fit very tight. You need to use an actual balancer installer to put them on. I currently have two of them and both were tight going on.
 
You must mic the crank, measure the bore in the damper and make the hole in the damper .0008-.0010 smaller than the crank. That’s how much press for you want. Any more than that and you can get into galling. Any looser than that and the damper looses its ability to control harmonics.

If you can’t measure accurately find someone who can.

Also I never ever press a damper on dry like that. I use anti-seize on the crank and a little in the damper and then use the tool (or what you have...all thread and a nut) to pull it onto the crank.

Pressing the damper on the crank without some form of lube is a bad thing.
 
Ok. So the snout is 0.030 longer than the stock one. That means ill have to shim out accessories. Sound ok? Or do i turn .030 off of it since its mine now.

Thanks for not beating me up too bad.
 
Fluidampr brand are the tightest balancers I have ever encountered. like YR said you need to hone it out a little bit.
 
my old micrometer says its 0.025 bigger at this point. I'm staying calm and going to re measure. I lightly did the emory i swear. Just the high spots, barely took off the dirt. Ha ha i know ....DIRT???!! ill re measure and use a little moly assembly ... at least the grooves will line up

Thanks fellas.
 
what do you think about the snout being longer than stock? No biggie? Or get her turned?
 
clementine said:
what do you think about the snout being longer than stock? No biggie? Or get her turned?
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What do you mean the snout is longer? The FD is thicker than other dampers so you either have to shim the water pump and alternator out to line the belts up.

EDIT: .025 undersize is a TON.

I have a BFN ITB FD out on the shelf. Tomorrow I will measure the bore on it and post the size. Plus I have a new crank out there too, so I’ll measure it.

I can’t remember one being .025 under. That’s a TON. That’s a bunch to hone out.

I’d have to think about that if it is that small. No way would I hone that out. I mean honing .0025 out is a bunch and you’re saying it’s 10 times that.

If that’s true, I’d throw it up in the lathe and a 4 jaw, indicate the hole in and bore most of that out.

If it is .025 small that’s a WOW. Mine better not be that small. I haven’t measure it yet.
 
Sorry....025 BIGGER hole. sticks out 0.030 More than stock.

I'm fine with shimming pulleys /AC compressor... no power steering.
 
I meant that when i measure the length of the bore of the damper ...its longer .. so it sticks out .030 further than stock. It sticks out a full 0.100 from the face of the crank .
 
I have put my fluid damper in the oven @ 200deg for 20-30 minutes, pull it out and use some heavy gloves to slide right on to a cold crank.
 
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clementine said:
Sorry....025 BIGGER hole. sticks out 0.030 More than stock.

I'm fine with shimming pulleys /AC compressor... no power steering.
Click to expand...
...so you're saying the I.D. of the balancer is .025" larger than the crank snout, and it was tight?? It would be so loose there would be no 'friction fit'...that doesn't make any sense I must be misunderstanding...
And the length of the balancer's snout is irrelevant, the pulley mounting surface is what matters..
You won't know what that's doing for certain until it's on and all your pulleys/accessories are installed. Then you can see how they all align. The exact thickness of the (presumbly aftermarket?) crank sprocket and whether or not you use an oil slinger can affect that too.
 
Ok. Good info. I'll give it another measure and dirty eyeball tomorrow. I like the heat trick, and that won't affect the material adversely? I agree that my measurements do not make sense. So ill try again tomorrow. I really appreciate the knowledge you guys have. The car is gonna be totally bitchin when she goes together.

Goodnight FABO!
Ill send pictures mañana
 
Silicon is 300F stable so heat it up to 300F (they say boiling water, 212F) and then push it on as far as it will go. Use the jacknut method for the rest. No honing necessary. Never mentions that in the literature. YOu may have pulley misalignment but your goal is to bottom out to the slinger and crank cog.
 
clementine said:
I meant that when i measure the length of the bore of the damper ...its longer .. so it sticks out .030 further than stock. It sticks out a full 0.100 from the face of the crank .
Click to expand...

I've read about a lot of the Fluidampers being too wide resulting in having to make accessories line up. That's why I won't use one. That's just stupid. None of their Chevy dampers are like that. I don't think any of the Ford ones are either, so it's something about THEIR tooling they don't want to change. ...and I don't know about being too loose as to affect harmonic dampening. Of course you don't want them fallin off or floppin around loose. Toyotas have had slip on balancers for decades and they run for a LOOOOONNNNNGGGG time. They will slip right on by hand, although they are retained with a bolt, of course. They do get "stuck" after years of service but all it takes to free them is a prybar on each side and they pop right off. There is zero press fit. I completely agree with honing them. But don't feel too bad. I recently destroyed a Rollmaster slant six crank gear for basically the same reason. It was really tight going on. I had to remove it after mockup. It would not BUDGE. I had to end up cuttin the beeotch off with an air chisel. When humans are involved, it can happen.
 
So, i think that turning the end of that SOB would be fine. Everything would line up. No biggie. It's not like i can warranty the thing. Make it the correct length, no shimming.

Thanks for all the advice.
FABO RULES!
 
Rusty, the old design fluidamper did require special pulleys because of the thickness. They have since redesigned it and they accept stock pulleys now. Yes it was a real pain in the butt getting the correct pulley and your options are very limited.
I do recall mic'ing and honing my first one to fit. The second one I got fit good out of the box.
I agree on the anti-seize.
 
clementine said:
Sorry....025 BIGGER hole. sticks out 0.030 More than stock.

I'm fine with shimming pulleys /AC compressor... no power steering.
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Uh ok ....dumbass here....

So i was measuring the leading edge (the side of the balancer that you put on first) of the balancer, which is a bigger hole, and comparing it to the OD of the crank. Of course its 0.025 bigger. Duh. My micrometer jaws for measuring ID are short and could not get by the thick azz balancer, so gee whiz pop, ill just measure the other side...

So. I'm going to have 0.030 taken off the snout to get stock depth. Ill bring the stock balancer for comparison to the machinist. And he will measure the ID and make sure im around that 0.008-0.010 smaller number previously mentioned. Ill measure the key width. Get her heated up and slide it in like prom night!

Thanks again, sorry, but this is who yer dealin with.

See where it hits the dial?

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Okay so you're talking about the rear of the hub being longer, I misunderstood that. And FWIW that's not a great way to take an inside measurement, it's not going to be accurate... you really need an inside micrometer. Get a solid repeatable number on the crank snout and let your machinist get that I.D. measurement. (at that point I'd have him hone it too if need be..you're already there). I don't ever heat them, I like to be able to get them off without drama...
Fluidampr specifically says not to heat certain models, and for others they say not to heat above 250 or 280 so if you're dead set on heating it read your instructions...
 
Copy that!
Thanks. Its gonna be great!

wow! the machinist actually come and picked up both balancers and did some measurements.
 
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clementine said:
Copy that!
Thanks. Its gonna be great!
Click to expand...


As pointed out, you can NOT a measure your press fit like that. So let’s cover some crap that’s in this thread.

Fluidamper has instructions. They are quite plain. They call for a PRESS FIT of .005-.0015 which is why I said it needs to be .0008-.00010, right in the middle. If you can’t hold that tolerance, you shouldn’t be doing the machine work.

It’s NOT a Toyota. There are some FD’s that require different press fit. That’s why there are instructions with the damper. If it slips on, it will not function correctly. That’s right from FD’s mouth, not some guy on the internet who has never used a FD or anything other than an OE damper. They NEED press fit to work.

Ever see a crank snout that is all pocked and gouged up??? That’s the first clue the damper isn’t working. Sometimes it’s because the damper is just junk for any number of reasons or there wasn’t enough press fit. Loc-tite will NOT fix it.

Too much press fit and it can split the key way. When that happens, it’s a mess. It can happen when installing the damper, but I’ve seen them fail on the car. Pretty hard to unf*%k that when they let go. Again, that’s why there is a tolerance.

Do NOT machine the end of the snout to make it the same length as any other damper. It’s nOT made wrong. It is thicker than an OE damper. There is a reason. And that reason is to get the weight of the inertia ring heavy enough without making the OD of the damper any bigger (7.25 inches is all the bigger it can be...if you go bigger than that you run into other issues) so to get the weight they needed they made it thicker. IIRC, Chrysler made the Hemi damper thicker to do the very same thing. BTW, they have a new part number for the SBM with a recessed face so there isn’t a pulley alignment issue. Also, March Performance has pulleys with the correct offset for your FD. There may be others that have them too.

Do not over think this. If you aren’t 100% sure of this, FD has a phone number and they answer it. Call them and ask them. They made it. Not a bunch of guys guessing on the internet giving bad advice.

Two last things. I have never seen FD EVER say to heat a damper to get it on. Not in water, not in the oven, not any other way. If the press fit is correct they will go on smooth and relatively easy with the proper tool. That ain’t a hammer. What you have is perfectly fine. Use anti-seize. That’s in the instructions.

And, if you read the instruction you’ll notice that FD says to NOT hone their damper. That’s in there for a couple of reasons.

One is there are some brands of dampers that are ALL undersize and you have to hone every one of them. This is not true with the FD. They are machined to OE dimensions so it is rather rare that honing is required. I’d the press fit ISNT what the instructions call for, then you need to hone it.

The other reason they say not to hone it because they don’t want it honed with a hand held hone. I do mine in the rod machine. It needs to be straight and round and you can’t get that with a hand held hone.

Here are the instructions. If something isn’t clear, call them. They love to help sort this stuff out.

https://fluidampr.com/wp-content/uploads/4NFA11_Standard-Damper-Install_11-17
 
Thank you yellow rose for explaining. I sent it to the machinist because i couldn't measure properly. He builds motors. Ill reiterate the undersized element of our conversation and not heat the damper.
 
Ya, so the machinist got back to me and it turns out that it is only 0.005 undersized hole and that it is not really much longer than I had previously thought. Moving forward I should have that puppy back on tomorrow and it should end well. I really appreciate all you guy's feedback and I have learned a great many lessons on this one.

Thanks again All.
 
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