Fluidampr install tips for SB MoPar

[66340SEDAN]

I am sure many here have a Fluidamper harmonic balancer but I thought I would point out some differences and some tips for an easy install for some thinking about this swap..... mainly the crank pulley cause the balancer is thicker than stock.

I have a 340 with a steel 1970 crank (internally balanced), when I built the engine I went with a cheap aftermarket harmonic balancer, probably China made but it worked great and came with weights you can bolt on for later 340 and 360's as well so i'll keep it for future use. I bought a used Fluidampr and finally got around to getting it ready to go on.

I am running the 70-up style stock pulleys, single groove lower one. The Fluidampr is thicker than stock, therefore, if you use the same lower pulley, it won't line up with the alternator. I went to a junkyard and found a single groove one on a 1969 Satellite with a 318, this is narrower than the 70-up ones and has a smaller diameter, so it will also act kinda like an "underdrive" pulley and maybe free up a little power...any SB 64-69 SB pulley should work for this. I did have to grind out the center hole a little to get it to fit over the lip on the Fluidampr, you will have to make one of the mounting bolt holes a little bigger too but fits nice and bolts on tight, when set on the balancer it lines up nice and should work great.

Here are some pictures :glasses7:

 

[66340SEDAN]

I do have one question, will I need a longer crank bolt to hold this on? Or will the stock one be long enough and have enough threads? Thanks

 

[fishy68]

I do have one question, will I need a longer crank bolt to hold this on? Or will the stock one be long enough and have enough threads? Thanks

I'd measure it to make sure but being it's about 1/2" thicker it's quite possible a longer one is in order. Last thing you want to do is yank the threads out of the crank.

I have ran into that problem of balancers being too thick before but never thought about using the 69 on back pulley. It was used with the shorter snout water pump so it makes sense it'd work

 

[moper]

You also should be using an installer - the crank bolt it not designed to be an installer. It's a retainer. I've found new balancers can be very tight on the crank (which is good) but you really need the right tool to get them on safely.

 

[fishy68]

You also should be using an installer - the crank bolt it not designed to be an installer. It's a retainer. I've found new balancers can be very tight on the crank (which is good) but you really need the right tool to get them on safely.

True.

 

[highflyer]

this is what I use..its actually a greenlee punch pulling bolt and bearing for pulling large chassis punches thru ...j

 

[swinger340]

I do have one question, will I need a longer crank bolt to hold this on? Or will the stock one be long enough and have enough threads? Thanks

Yes you will need longer bolt. I found one at hardware store grade 8 3/4-24 x 3 was around $4. I am having same problem as we speak. I need that crank pulley..... LOL!!!

 

[66340SEDAN]

Yes you will need longer bolt. I found one at hardware store grade 8 3/4-24 x 3 was around $4. I am having same problem as we speak. I need that crank pulley..... LOL!!!

You just need a single groove 64-69 LA small block pulley.....don't pay 340 price for one, they are all the same! Check eBay or start a "parts wanted" thread 8)

Thanks for the bolt size, should be easy to locate from a hardware store.

 

[66340SEDAN]

this is what I use..its actually a greenlee punch pulling bolt and bearing for pulling large chassis punches thru ...j

Sweet, looks like it would work great! When I installed the one I just removed, it was new and I put some anti-seize on the crank snout and the balancer went On with ease just by tightning the crank bolt. If this one has more resistance, I'll have to find an installer tool.

 

[goldduster318]

A great alternative to the fluidamper is the "Pro-Race", I have this one on my engine and it allows the stock pulley to be directly bolted on and have the belts line up.

It's a nice piece:

 

[RobertP]

just received my fluid damper for my car, the only modification i would have had to make was to oval out one hole. but i'm running the march serpentine belt kit so the hole is already elongated. the fluid damper is thicker than the stock damper but the spot where the pulley mounts is recessed in so it will line up perfect. mines the 720301 fluid damper.

 

[Kryogenic]

I am sure many here have a Fluidamper harmonic balancer but I thought I would point out some differences and some tips for an easy install for some thinking about this swap..... mainly the crank pulley cause the balancer is thicker than stock.

I have a 340 with a steel 1970 crank (internally balanced), when I built the engine I went with a cheap aftermarket harmonic balancer, probably China made but it worked great and came with weights you can bolt on for later 340 and 360's as well so i'll keep it for future use. I bought a used Fluidampr and finally got around to getting it ready to go on.

I am running the 70-up style stock pulleys, single groove lower one. The Fluidampr is thicker than stock, therefore, if you use the same lower pulley, it won't line up with the alternator. I went to a junkyard and found a single groove one on a 1969 Satellite with a 318, this is narrower than the 70-up ones and has a smaller diameter, so it will also act kinda like an "underdrive" pulley and maybe free up a little power...any SB 64-69 SB pulley should work for this. I did have to grind out the center hole a little to get it to fit over the lip on the Fluidampr, you will have to make one of the mounting bolt holes a little bigger too but fits nice and bolts on tight, when set on the balancer it lines up nice and should work great.

Here are some pictures :glasses7:

I just wanted to take the time to thank you for posting this research. I am just now running into this problem and it is soooo nice to find some data on it so the wheel doesn't have to be recreated again. I called Fluidampr and the guy I spoke with didn't really know the answer. I did get that the earlier Fluidampr's don't even have a serial number on it.

In case anyone else runs into this problem, I ordered some pulleys (I needed aluminum) and found that CVFRacing makes a set for the 67-69 that should work. Once they arrive ill update this to let everyone know.

Thanks again 66340SEDAN

 

[mikedevore]

Moroso also makes the two different height pulleys'

 

[rigger3006]

good to know,thanks! have a shiny new fluid damper shelf for 2 yrs now, on the pulley hunt now!

 

[RobertP]

Here's the fluid damper and the March pulley system and how they line up.

View attachment image.jpg

 

[pishta]

early CAT balancers were just like the fluiddampers, too thick and not recessed for the pulleys. Later CAT dampers are still too thick (!) but are recessed for the correct pulley. CAT says put balancer in boiling water for a few minutes and it will slide on. I found you can use a "Lisle" brand balancer puller bolt as the jack screw: mount the balancer, thread the bare 3/4-24 puller bolt into the crank until it bottoms and run a washer and nut onto the jackscrew and start turning the nut to press on the balancer. You can even hold the jackscrew with its 9/16 hex end so it doesnt turn the crank. Those bastards go on deeper than you think, and at about 135 ft/lbs too.

 

[Kryogenic]

Hey guys, I got the pulleys in the mail and they align perfectly!

Thanks

 

[Kryogenic]

early CAT balancers were just like the fluiddampers, too thick and not recessed for the pulleys. Later CAT dampers are still too thick (!) but are recessed for the correct pulley. CAT says put balancer in boiling water for a few minutes and it will slide on. I found you can use a "Lisle" brand balancer puller bolt as the jack screw: mount the balancer, thread the bare 3/4-24 puller bolt into the crank until it bottoms and run a washer and nut onto the jackscrew and start turning the nut to press on the balancer. You can even hold the jackscrew with its 9/16 hex end so it doesnt turn the crank. Those bastards go on deeper than you think, and at about 135 ft/lbs too.

I know I shouldn't do it, but back in the day no cash = put a little grease on the crank tip, take a rubber mallet and tap the balancer a little bit on, half inch or so, and screw the bolt down and impact-pull it into place. I'm not telling anyone to do that, but its worked for me for 25+ years.

 

[grimreaper]

I found out about the longer bolt requirement the hard way too. I was able to solve the problem by using a piece of hard all thread and a nut. There were still good threads deeper in the crank that the stud could grab. Now whenever I use a balancer other than factory I thread in a piece of hard all thread and then put on the nut and mark it at the end of the nut. Then remove, cut and reinstall and it's all sweet looking when done. Kinda matches the main and head studs

 

[madscientist]

You should NEVER install ANY brand of harmonic dampner without measuring the crank snout and honing the bore of the dampner to provide a press fit of .0010-.0015.

If you have less it won't function correctly (among other things) and if it's too tight it can break off the crank snout.

ALWAYS measure it.