Harmonic Dampers And Balancers - What they do, Differences, What To Look Out For, When To Upgrade 

I recently put a Fluidamper on my 24V Cummins 5.9. The stock one was still perfect, but had read good things about Fluidamper. What a world of difference! Idle and high RPM smoothed out, and clutch chatter (especially reverse) was just gone! I wish I had put this in years ago!

Great video Tony! Can you maybe cover the mystery of drivetrain vibrations? U-joints, differentials, mounts, etc? Thanks for all you do!

When I tore down my 289 I was dumb and didnt know the damper was just pressed together, used a gear puller on it, you know how that goes 😭

On mopars, I've run into more dampers where the outer ring has walked than not. Even on ones where the rubber seemed okay. I no longer mess with factory units on a fresh build anymore.

Great video. I've always taken harmonic balancers/dampers for granted. I never really knew just how important they are, that they could go bad and or that even though they came off a similar engine that they might not be interchangable. Bottom line - I just learned a lot of new things and I've been around cars all my life. Thanks for putting this together.

Tony, I'd like to see you follow this up with discussion of balancing torque converters. I remember back in the day when dinosaurs roamed the earth, some guys using smaller 6 cyl torque converters for higher stall speed, and rebalancing. I never understood the voodoo on all this. Also, B&M used to make a flex plate with weights so that you could run the 360 externally balanced engine with torque converter for a 318 or 340 internally balanced. That part is no longer made, from what I understand. Any insight into all this would be appreciated.

How about a video on torque converters?!?!

I would like to see a video about engine cooling systems. Radiator size, air flow, heat cores ect..

My harmonic balancer went out on my Subaru put a new one on it pretty easy fix love the Chevy and Mopar knowledge old school tool thank you 💪

I never gave a second thought about these. Granted i never build a engine past stock either. Thanks so much for the fountain of knowledge. Now I know more for the future.

I thought I knew at least a little bit about dampers, until I watched that video. Another huge score, Tony! Thanks.

I had the whole damper fly off a 64 Chev 327, that was before they added the center bolt. And I also worked on a 86 IROC Camaro 305, where the inertia ring slid backwards a sawed a hole right thru the timing chain cover. Fun stuff.

I've been considering replacing the damper on my 56 Ford. As far as I can tell it's still original and I've been warned about the damper separating as you said and becoming a deadly weapon of destruction. It still lines up perfectly when I check the timing marks, but it's in the back of my mind whenever I take it out for a ride.

Can you make a video on an overview of radiators? Comparisons, pros and cons, brass, aluminum etc. I’m very curious on what your thoughts are

I've seen the inertia ring slip on modern cars as well, including a late model BMW. Easy way to tell if the inertia ring has slipped. Just look at the key-way, is should line up with the TDC notch.

I had one repaired, for a 66 Pontiac 389 engine. It cost $130. Company called “damper dudes” in CA. Good video Uncle Tony!

I had a dampener come apart on my driveshaft in an 02 S10. Ended up just hacking it off instead of dropping the shaft. You could actually feel a difference in acceleration in that extremely under powered 2.2L after removing that big hunk of iron

Thanks for this one! Always learn something useful... I had one fail on a slant six, too, but it never flew off, it just started throwing the belt. Cheers from Canada!

I needed a crank for my 383. I was told 400 crank would work. And it did except for bad vibration. I finally figured out that the 383 was internally ballenced and the 400 was externaly ballenced. So installed 400 balancer and 400 torque converter. No more vibration .

Good video! Simple stuff that no one thinks about unless something goes wrong with it. The only time I really think about it is when I'm setting timing. It can happen on newer stuff too, I saw one fail on a Ford Fusion one time.

Excellent work good communication skills I learned a few things from this video I'm just a mild backyard mechanic.

You need to go look in your archives, where you showed everyone how to start your engine 32 degrees total timing, the distributor video, yes that one. God bless you and your family.

Video suggestion: gear head nerd video on the flywheel. Although it seems simple, much like the harmonic dampener, it has some interesting science to it 🤗

Hey just wanted to say, this is the most important video I've seen from you in a while. This is very important to engine timing. In order to get that extra HP out. Out of your car always start with the timing, provided everything else is good. I've advanced the timing on American V8's for years. Nothing but happy customers.

Tony, great video. Thanks! I have been a shade tree mechanic since I was a kid so I feel like I know what I'm doing most of the time. However, every time I watch your videos, I always seem to learn something new. Thanks for sharing your unique knowledge, brother! Chuck

Tony, You hit your head on the nail when you talked about the affects of accesories driven off the front of the crankshaft. They add rotational inertia that helpd damp out the rotational pulses in the crankshaft. The rotational inertia of the accesory drive system doesn't compare with the rotational inertia at the back end of the crankshaft, provided by the flywheel and clutch cover is you have an Amish transmission or the torqueconverter if you have a slushbox. The front of the crank needs additional rotational inertia, or the crankshaft will fatigue from winding and unwinding due to the torsional pulses from the connecting rod forces on the crank pins. The harmonic damper reduces the torsional "Ringing" of the crankshaft, which reduces stresses in the crankshaft, preventing fatigue fracture of the crank. If your harmonic damper fails, it's less expensive, but not as much fun, to replace it with another harmonic damper instead of a belt-driven 8-71 blower.

I have Grumpy Jenkins book. He described a method of putting screws through the inertia ring to keep from flying off Of course that was serious horsepower/ RPM.

Hello man, how are you?? Firstly, I need to tell you that I have always liked your channel and all the topics you post. I'm from Brazil and I started working with Dodges since I was 14 years old. You always post content with great technical topics and always remind me of my youth when I was learning about Dodges. CONGRATULATIONS FOR ALL THE CONTENT YOU POST and know that I am learning a lot more and more from you!! Hug !! I hope that one day I can meet him in person.

Threw the ring of my Jeep 4.0, luckily I was idling in the supermarket carpark so no damage.

Great video! Simple and basic stuff, but very important and overlooked too often.

Man I love Uncle Tony HOWEVER I just wish he was die hard Chevy guy!

When my father and I switched out the 302 for a 351 Windsor in his 83 F 100 Ford truck we had two problems to deal with when initially trying to start it. 1st, was the firing order is different 2, was the timing marks on the harmonic balancer was wildly off, no doubt due to being shifted. We ended up findings top dead Center with a dowel . Good to know that they can fly apart!

I had a 97 Ford triton 5.4 that slung the inertia ring off the damper going 70mph on the interstate. Funny thing is it didn't do any damage at all and the only reason I knew something was wrong is because the alternator quit charging when it slung the belt off. I didn't even realize the inertia ring was missing till I went to put the belt back on and noticed it was waaaay too lose

Good job Tony and thanks, but you forgot to cover the sizes with a tape measure. The reason I was watching your video and searching the Internet is I have a 76 Corvette street and show only. I am in the process of upgrading the 350 engine with 750 Holley double pumper with 2 inch aluminum spacer. An Eldelbrock Performer, a Roller Cam with around 2200 to 5900 RPM, with linked Roller Lifters and Aluminum roller Valve rockers and a 10 inch 2700 to 3000 stall converter from Assault and Flotek 180cc/64cc aluminum heads. I am halfway through the project now but this balancer thing I have, came up again including timing questions. I Purchased the 8 inch on Amazon from Professional Balancers who says it is for a 76 Corvette. I was told by Google searches that doing so would be a benefit to install an 8 inch with an after market Harmonic Balancer like Professional Products (80002) 8" Harmonic Damper for 350 SB Chevy because of the aftermarket changes I am making. The OEM is a 6 3/4 balancer. Any thoughts on that.

As a kid I swapped a 327 into my dad's 64 Chevy two ton truck. (swapped several into that because the 327 was a horrible big truck engine) Anyway this motor was a backwoods buy, a runner. Noticed they put the damper on with a sledge hammer, didn't think it'd hurt. So the old man wants a Quadrojet and I'm getting the linkage right, and of course because 14-15 you test it by revving the crap out of it! So I'm in the cab revving it and BAM! Outer ring came apart and I was just laying over it revving the damned thing a minute before. Oh yeah a chunk of that would go right through a human body.

I saw a Nascar team, and they had the type of Damper that has all the O-rings inside it - and they would actually take it apart and tune the amount of rings inside while on the Dyno for each engine.

Had a balencer on my amc 360 start to seperate.. the rubber was pulling out. I used rtv on it to hold it in while i got a new one. New one works great. My 98 4.0 Grand Cherokee after about 280k miles needed a new balencer. The engine made weird noises in the cabin.. looked at the balencer and it was wobbling. New one in and it sounded like normal again. Engine now has 400k miles

Good video; didn't know the difference; and now i do; thanks !!!! Always something new to learn thanks to videos like this !!!!!!

Wow so much good stuff i didnt know i planned on taking most of the accessories off my square body and i never in a million years come up with needing a after market balancer/ dampner. Thanks forbthe knowledge and the headache saver

On my 80 z28 I had in high school I kept hearing a scraping sound....it was the inertia ring scraping the timing cover!!!

Another insightful educational video. Thanks UT. Keep em coming buddy.

This is perfect timing just replaced one on my jeep.

I bought an old corvette. Very stock/original with a smooth running original engine. Despite there being no sign of the damper being bad I went and replaced it anyways. I figured after 50 years it was time for it to retire. Seems that the LS engines in later year vettes have issues with their balancers. I’ve met a bunch of C5 vette owners who said their inertia ring had moved enough to start rubbing against the water pump cover.

Had one come apart on a 318 in a late 70s Ram charger. Luckily the alternator belt held it on there. Beat the crap out of the front cover though!

Great stuff again Tony

thanks, such a great and detailed video, as they say you learn something new everyday! ...keep em coming Uncle Tony

Always found it interesting that a water-cooled mk1/2 vw had no balancer with AC, but if AC equipped they had em.

Great explanation Tony. Can we get a follow up video on how to set up an aftermarket damper to match an aftermarket rotating assembly?

Yes, thank you

another one that comes apart quite alot is the 3800 gm v6

Hey unc Tony...funny you bring up balancers .... especially 4.0 jeep just had a failure on mine,your correct. Mine had a oiling problem due to the crank seal.All happy now new seal & balanced TA DA!

Cool! I had wondered what a harmonic balancer did and how it did it. Thanks! 😀

Tony there is a company called the damper doctor that can repair the damper based in California.I had one made for a iron duke that just had a pulley

That's a really good explanation. Thanks from Australia.

OK I subscribed to your channel. Keep up the usefull information. Oh BTW I've discovered Rochester carburetors are the cat,s meow.

Had the one on my 3.9L dakota start coming apart. Checking timing i saw it wasn't right so I replaced it. My 79 camaro had the inertia ring back off and start eating the timing cover. My 85 d150 will get a new one when I go in to do a timing set and refresh. Very good info as always 👍

I've been rebuilding automatic transmissions 45 YEARS now I'm 59 as a young man my Dad ask me to put a harmonic balancer sleeve on a 350 Chevy engine ,,, after the new sleeve the CUSTOMER sead , WOW THAT'S ABSOLUTELY the smoothies my car has ever been ,,,,,, OH yeah I found a chunk of tar clogged up in the balancer and chipped it out with a screwdriver and hammer , I didn't even know what I had done ,,, but AT 14 years old a 20 $ tip gave me a good idea to stick with it ,,,, no pun intended 😁👍

Two years ago the ring became loose at 65,000 miles in my 2006 Mustang with a 4.0, taking out the crank position sensor in the process. While looking for a new damper, I found out that a 2010 Mazda B4000 pickup with the same engine also had the same interchange part number and was exactly the same. This was true for other models of the era as as well, like Ranger, Explorer, E-150, E-250 and more. It was cheaper too so I installed it. Never had an issue since but I keep an eye on it.

Great info. Actually, it's the shearing of the elastomer between the outer ring and the hub that does the damping.

The " Harmonic " part aint needed after installing the GM 6-71 blower . Solid hub drive .👍

Can you do a video explaining leaks and sleeves for the harmonic balancer/damper where they attach to the crank through the front main seal?

Tony,you need to define the difference between Internally and Externally balanced crankshafts.

Grandpa had the d310 in the 756 rebuilt in the 80s. They fired it up and anything over idle, it had a bad vibration and the front tires of the tractor started bouncing on the shop floor. The mechanic's helper had dropped the damper pulley. The impact ruined it.

I'm surprised there's no mention of the clicky clacky 3800 dampers of the 80s and 90s

Thanks Tony

My 429 in my thunderbird has the damper integrated into the crank pulleys

The part about designing in the accessory drives helps reinforce a thought I had about a 330 Olds engine I had which had no damper at all (just a counterweighted hub) and relied on the accessories to do the dampening.

Uncle, how much you can mill a pair of 360 heads before having issues with aligment on intake and block? Mexi 360s has 8.0 cr!

The one reason to use a factory dampner/balancer is reciprocating mass, if HP and revs are your concern, this is a key element.

Great timing. I ordered a replacement damper for my mom's car. The rubber had several cracks and I didn't want to take any chances.

UT, very impressive. Very well done explanations. Thank you UT!

I thought about going to a clutch for my 304 but the externally balanced flywheel wasn't a easy thing to find. I still might if I get a 360 crank.

Damper Dudes can re-vulcanize your old dampers.

Ok Unk, how about talking about engine balancing. I'm just a "take it to my engine guy" but I don't really know what he does -- or how to know if he's done it right.

Thanks for the video my buddy learned the hard way in 1977 he built a 364 small block Chevy13 to 1 compression it was dynoed with the correct balancer but he didn't own the balancer he ordered a balancer but he wanted to go racing so he put some random balance around oh looks the same on the second pass down the track it exploded the crank literally blew out the bottom of the motor broke the tranny broke off put fluid under the tires lost control hit the guardrail it was amazing every man broke the crank was laying in a cross member what a hard lesson to learn he said oh I noticed a little vibration yeah what a dumbass that was a $4,000 mistake that was a lot of money back in 77 have a great day balancer lesson learned thanks for the inspiring videos and don't forget if you have time to watch Cold War Motors

Excellent video as usual. Myself, I use fluid dampers exclusively if it is available for the engine. From what I've learned from D.V., it's the most effective at the job.

My brother had a mitata with a bad valve cover gasket, leaked oil all over the front of the engine. Had his damper/pulley fly apart from that oil soaking. Chewed into the timing cover when it was walking around before it flew off. When it flew off it pressed into the rad fins, caused a slow pressure leak in rad, eventually had to replace it. Thankfully I was able to find a replacement timing cover, and replaced it when I did the timing belt & water pump. Should've just fixed that valve cover leak when it first started...

Definitely didn't know that keep it coming taking notes 👀👀 🍿🍿

Loose spinning metal can rub a hole in the front plate where your timing is. Seen an oil leak from such wear

Great knowledge thank you!

I saw one come off once out of a 70 Chevy 454 at the 1/8 mi line. it beat the car to the turn off and was still spinning when the guy got out and put his foot on it to stop it. He said it destroyed his engine. I saw another come off a mustang, it bounced twice and left the property, headed south.

Only thing to add is fitment, and that varies. Maybe 0.0015" interference [damper vs snout] is not a bad rule of thumb for something of unknown origin?

BRILLIANT!

Uncle tony is so wise.

Does torque or HP "Camshafts" are factors or only the High RPM limit for the factory used Damper and Balancer. Some engine with huge cams runs very rough from big Lobe !!! And have rave limiter. One thing i can say to this is... If Uncle Tony uses the "Aftermarket" word so many times. It must be crucial to these applications. I learned that anyway ! Hehe

Cool video. I myself will usually replace the original harmonic damper when a repair requires removing it or during a rebuild. The reason being, I want to avoid the consequences of the rubber being potentially “expired” in some way. I figure at that point it’s just a chunk of spinning metal not protecting the crank. I’ve heard this condition when prolonged can cause a crankshaft to fatigue and break. Also, did you know before the 1970s Chrysler used an asymmetrical bolt pattern on their dampers for the pulley? Ask me how I know...

Good stuff UT!

I had a stock damper go bad, wasn't obvious but when I went to check my timing one day when the engine ran poorly.. any way new damper fixed all

I've got a ford 361 truck engine. I put a 391 flywheel on it that had weights on it and I put a crankshaft pulley from a 330 truck engine. Seems ok so far...hope so.

Can you do water pumps or distributors

My British cars never came w/ balancers. Just a plain V-groove pulley. Those little engines were internally balanced and didn't require one. Now, only if the rest of the car was built with care...!

Tres thank you

A “Neutral Balance” dampener should all be the same; think of it as a rim/tire the balance weights aren’t always in the same spot.

Hey Tony I noticed the 360 down here that you didn't discuss it was the one that's supposed to be used with the manual transmission the damper on automatic is different for 360 something I found out I've been building engines for years be a good thing for all Mopar guys to know

Reminded me of the day I attempted to remove my damper using a 3-jaw puller. LOL

I would like to see fluid dampers And other after market dampers explained just saying othere Than that great video. Oh tear down a flat head Moter you should see the ones in World War Two dodge army trucks

Even on the Big block Chrysler 361 I have has the stock dampener. But I imagine the dampener will create quite a racket when it gets loose. As the accessory drive 4 belt pulley is in the way of the dampener from "coming off" so essentially trapping the outer ring. I'd think that the outer ring will be pummeling everything in it's vicinity. If It does come loose! On big block Chrysler stock dampeners pre-1964. To inspect the health of the dampener, the 0* degree mark on the weighted outer ring should be about 90* apart from the crank indexing stub.

Thanks for the video. How do you know which balancer you need when some internal pieces of the engine have been changed?🤔

Stripped a bolt mounting the pulley. Is it okay to just leave that bolt out? Its a 69 440 steel crank. No racing just a street car.

the resonance frequency