mdricken

OK, I was at O'Reileys and the Pathetic Parts People told me that I could just hammer on the damper, probably because they didn't sell an installer tool. Anyway, I got home and all of the shop manuals I read (Hanes, SBC Engine Assembly Book, Car Craft) said to use a tool.

So I hammered it on anyways since I have an old 305 I don't really care about anyway.

Is it really that critical??

3rdgenstm

Now, just 'cause it is a 305, don't take any lesser steps with it than any other engine. No, I wouldn't hammer it on. If you hammer on it enough, it may throw it out of balance thus cancelling out its function. I have set it in place and then tapped it with a piece of wood a smaller mallet, then used the crank bolt to pull it into place.

Anyone have any other suggestions?

Ward

iTrader: (1)

I did pretty much the same thing as you did. I got a small section of a 2X4, placed it against the face of the balancer, and used a hammer to ease it on. I say ease, because I was not hitting it very hard, no need to try and get it all the way on in one whack. Once it was down most of the way, I used the crank bolt to pull it down the rest of the way.

Vader

I hope if you ever require CPR, someone doesn't ignore the manual and drives a dump truck over your torso (it's still a chest compression, right?).

The reason to avoid the hammer method is described by 3rdgenstm. The impact of the blows can loosen the inertia ring on the elastomer element, causing it to fail and allow slippage. That slippage can prevent the damper from doing its job, allowing harmonics to eat your engine and snap your crank. You'll never know if it is slipping or not. Short of that, loosensing the elastomer can allow the inertia ring to fall off, or slip to the point where it is useless for timing the engine.

And you don't really need any specialized, fancy, prepackaged tool to get the job done right. A 5" piece of 7/16-20 threaded rod and a couple of mating nuts and washers is a lot better method. Even the Haynes manual knows better...

Damon

Another "real reason" not to do it is because you're throwing that hammer-blow shock force right onto the thrust bearing that regulates front-to-back play of the crank in the block. There are probably other reasons why it's a bad idea, too.

That being said, I did it for years before I knew better and I never had any bad results. But that's as much luck as anything else. Buy an install tool. It goes on SOOOOOOO easy with the correct install tool you'll break out in a fit of giggles the first time you use it.

Wishmaster's87IROC

iTrader: (4)

Can I bead blast my balancer? I want to clean it all up....Im kind of **** about things like that....when I remove something I clean the heck out of it...

I wanna get all the old crud and crap off of it...

Wishmaster's87IROC

iTrader: (4)

does this look normal for a stock balancer? I noticed this when I removed it just now....theres no way the puller could have done this....so is this normal? the way the center sticks out futher?

I dont mean to highjack his thread but I figured his question was anwsered and I didnt want to waste space and start a new one...

Damon

Looks like the outer ring is starting to "walk" towards the engine slightly. I had one do it so bad it actually started rubbing against the timing chain cover- what a noise that made!

If in doubt, always replace. It's not a lot of money for a fresh stock one.

Wishmaster's87IROC

iTrader: (4)

thanks for the reply...When the engine was running I didnt notice anything...its taken it 16 yeas to do that...I just dont feel like spending money I dont have to.

dans82bird

I use a piece of threaded rod and a nut; just make sure the rod is threaded all the way into the crank snout or else you could mess up the threads. Is it true those old SJ motors didn't have a hole drilled/tapped in the crank for the balancer, that their pressed on?

mdricken

But don't you have to ballance it with a machine when it is on the engine (which would require removing the engine)???

Damon

No, you don't have to rebalance. If you're REALLY **** I suppose you could but I've done a buncha balancer replacements in the car without rebalancing the rotating assy. and never had a problem. It won't be perfect to a single gram of balance or anything like that, but PLENTY close that you'll never have a problem.

All in all, having a fresh balancer that's maybe slightly out is still WORLDS better than having an old one that's chewed up, worn out and possibly slipping.

robertg

iTrader: (2)

when i rebuilt my 305 last year, the stock balancer looked just like that.

wishmaster, i sent you a pm about a balancer.

Viprklr

iTrader: (5)

So I take it after looking at Wishmaster's pic that the balancer isn't supposed to be domed but flat?

gmsmallblockguy

Well no it isn't supposed to look like that. Still you have to understand harmonics to know why that isn't a major problem.

Harminics are dangerous because they are basically over lapping sound waves that can amplify eachother and cause extreme pressure.
Sound waves behave simmilar to waves in water. Imagine a tidal wave joining up with another tidal wave. Now imagine a tidal wave hitting another tidal wave head on. Think of the force involved there. Water would splash out violently right? Sound waves do the same thing.
In iron and steel sound travels much faster than in air. Have you ever turned a brake drum? Heard that awefull squeal? Did ya know if you wrap some lead weighted rubber arround the outside it stops screetching? Thats because the combination of the rubber cousioning the vibration and the weight absorbing it stops the sound. Simmilar to placing your hand in the head of a drum or string of a guitar. This is called dampening. That is what your harmonic balancer's main job is.

If the balancer starts slipping the worst problem caused is that the timing mark won't line up. It will work as a dampener as long as it stays together and there is no direct contact of the outer ring to the inner save for through the rubber lining. A slipping dampener can be a sign that it wants to come appart and needs to either be fixed or replaced before it starts making metal to metal contact.

The real "balancing" of you rotating assembly is in the crank's counterweights. The main external adjustments for "balance" are weights on the flywheel. So as long as your balancer stays together for the most part it will be doing it's job of dampening harmonics.

I had a kid one time pull the outer ring off a balancer that was to go on a blue printed 305 that was to run 7,000 rpm redline.
Knowing the timing mark should be about 7 degrees retarded from the keyway I pressed it back on with the addition of a little gm black hi tak. We re-used it and last I knew that engine had been running after 3 years of use and abuse.

I lay no claim to being the authority on the subject this is just my understanding and experience of the topic.

Wishmaster's87IROC

iTrader: (4)

Ive been looking around and from all the balancers Ive seen Im pretty sure this is normal for atleast a stock SBC HB......heres a picture of a 6" balancer..

gmsmallblockguy

That is normal but in the previously posted pic the outer ring was at an angle to the inner showing that the rubber lining had let loose a bit.

Viprklr

iTrader: (5)

Thanks for the info.
I learned something new for the month.

DartByU

To correct what gmsmallblockguy said, the harmonic damper has nothing to do with sound waves, it's purpose is to stop the harmonics set up by the piston and connecting rod pushing down on the crankshaft, every time the engine fires and the piston forces the crank down it actually bends the crank a tiny amount, then when the power stroke is over with the crank will spring back just like a spring, this happens 4 times every revolution on a V8, the harmonic damper keeps all this springing from getting out of control, the crank would break pretty soon if not for the damper, that's why you need a good one, if the rubber insert is loose it won't do a proper job of dampening.