Here is a copy of the instructions that came with the Damper, it contradicts everything I have read ni regards to installation. They give you the option of hammering it on: SEE STEP 8 of the instructions

What do you think I am most likely going to use an installatiuon tool but I was just curious b/c alot of people say that this method is risky

 

Only after you've heated it.

 

i used a air gun when i did my girls 5.0 mustang made it so easy.. had the car done from tear down to the last bolt put back in, in 25 min

 

I can understand your concern. Hammering on the balancer has always been a "No, No". The directions do say the engine should be COLD and the balancer HOT, but even so, those directions are contrary to what many of us have learned not to do.

It also makes me wonder why. Why would Summit make such a controversial recommendation? I'm assuming it was Summit, and not one of it's suppliers, that actually made the recommendation.

But then GM comes along and recommends and shows a diagram of hammering on the crank gear on the 96 LT1 to install it. Where does that leave us?

For me, I don't have a problem with hammering on the crank gear but I would NOT hammer on the balancer.

Jake

 

I worked for a rubber manufacturer in a past job, and their plant in Northern Indiana manufactured harmonic balancers. First grey iron is cheap, will have internal stress and is prone to crack. Hence, the reason you shouldn't hammer. The original method of manufacturing a balancer was to insert a piece of rubber between the inertia ring and the inner hub.

The next evolution was to glue the rubber between the two rings since separating and slipping is a common failure mode. Modern balancers are made out of nodular iron and steel.

Gray iron particles solidify in flakes upon cooling which propagate cracks, where nodular steel cooling is slowed and the particles solidify in spherical shapes. The formation of cracks is greatly reduced with this method, which is why you hear the term "nodular crank".

The new balancer rubber is actually bonded to the two rings simultaneously under 400 degree plus temperatures, pressure, and vacuum. This removes air bubbles, and fully cures the rubber to the contour of the pieces. In addition, significant advances have been made in the rubber, which is now oil and gas resistance silicone as opposed to the early HNBR or Viton. Additional gains have been made in the heat activated adhesive which is applied as a spray to the rings. You will actually tear the rubber apart before delaminating the adhesive. Too much adhesive causes it to fracture on itself between the rubber and the rings (this is actual adhesive separation at the microscopic level).

So with all of that, you can now beat on them with a hammer. Just put a wooden block in between to dissipate the energy of the hammer. Localized impact of the hammer head will overcome all of the crap mentioned above and make stress points.

I just installed one from Summit myself. Heating and lubrication is recommended so you don't damage anything and lowers the impact force required to drive it onto the crankshaft. Plus, you can wear yourself out with that much swinging.

 

It doesn't take much persuasion to put a hot balancer on a cold crank. Very different from beating it on while both are cold.

I don't like handling hot balancers, though.

 

That's GOOD to know.

Since I've never tried installing one that way I was just assuming (yea, there I go again) hammering one on would be as hard as the one I saw my buddy hammering on once.

I arrived at his garage just as he was using a sledge hammer take a full swing at his balancer to install it. You know, the sledge hammers with the 3-foot long handles and, what would it be, a 10 pound head. He looked like a lumber-jack chopping down a tree, LOL

Jake

 

If you have access to a proper installation tool why not use it? Certainly you can combine the two methods- heat the balancer + use the proper tool, and have the best of both worlds. Plus using the proper tool makes the installation SOOOOO easy compared to a block of wood and a hammer you will wonder why you ever did it the "brutal" way.

Hammering on a balancer isn't just a matter of damaging the balancer- it's also about damaging the thrust bearing surfaces that the crank rides against on the rear main bearings. Those surfaces are not all that large and take 100% of the force when you hammer on the balancer. After you're done all that hammering they still have to function as a lubricated bearing surface when the engine is running. If they were damaged or distorted by the hammering they won't be able to perform that important function very well.

Have I beaten balancers on with a hammer? Yes, I have. Did I have a problem becuase of it? No, I haven't. But would I recommend it over using the proper install tool? Absolutely not.