My Optispark decided to die on me ... note to self: don't buy the $59 Optispark's off eBay. It lasted about 10,000 miles ... the engine was a complete rebuild short of the crank and pistons, so no sign of any weepage from the water pump, and new seals on the opti and water pump so no oil from that source. I've now invested in an MSD Opti unit: ridiculous to sublime to mangle a metaphor.

The tear down was very straightforward until I got to the harmonic damper. Remembering that it was fitted and lightly oiled some 18 months ago, I was hoping that once I removed the three bolts, I could wrap it in a damp kitchen towel, blow hard and with three shakes of a cat's tail, it would fall off.

Well that didn't happen ... searched for the best solution, and with one exception, the only solution I could find on the Corvette forums was to raise the car, and hammer on the back of the damper with a small block of wood while turning over the engine between hits ... having tried that for an hour, I decided that there had to be a way to use a 2-jaw pulley removal tool.

I did find a someone who had posted that they had successfully used a 2-jaw pulley removal tool from HF. Since I had the same set, I decided to try it out ...



None of the three pullers would pass through the spokes of the damper, so I had to try and pull on the outer diameter (7.25"). The largest of the three pullers would not grip since the puller collar (where the draw bolt passes through) is too narrow.

OK ... there has to be a way of making this work. I knew that the longest of the 2-jaw puller arms would grip the back of the damper, but I needed to secure them at 7" or more apart so they didn't spring off the pulley when I tightened the puller draw bolt.

Voila, I have a machine shop ... I found a piece of 10" long 1.5"x0.675" steel bar in my short end pile, and started making chips ...



Nearly finished ...



The bar was slotted to allow the use of the two 8" long arms from the HF puller. It was cross drilled to allow the arms to be fixed to the bar, and finally, was threaded to allow the use of a long 0.5" UNC bolt.



Given the length of the bolt, the bar had to be inserted from above and the bolt fed carefully into the fan opening, and then the bolt was inserted through the loop in the power steering feed pipe in line with the crank bolt. Once the bar and draw bolt was in place, the arms could then be fitted to the bar, and the fixing bolts dropped into place.

It was a lot easier to access the draw bolt from underneath the car ...



I could easily get a ratchet on the head of the bolt, and then tightened until the damper popped off ... see below:




I have added a couple of dimensioned photos below in case you want to recreate the tool:



Another view:



Given my experiences with the eyeballed solution shown in the photos, I have attached below a dimensioned drawing that would be easier to use than my first attempt shown above (which is too wide and the bolt is too long !).




Please note: I cannot guarantee that the above adapter will work for you. If you do use the design, it is entirely at your own risk. If you are not sure if it will work, or how to use it, then visit your local dealership and avoid any pain and distress that might be caused by the use of the above tool.

 

That is a great tip. That would work great for pulling the discs on the braking system.
I used a Craftsman 6 inch Gear Puller part #946905 to pull mine last week. I put a tie wrap theough the other holes and sinched it up to keep the jaws in contact with the dampener edges. I used a 5/8" 1/4" drive socket for the puller bolt to set into.


Dang.. That is some dirty engine, right?

 

Glad to see another problem solver out there!

And your engine is clean compared to what I had to deal with 18 months ago!

 

Sand the rust off the hub/balancer mating surface and apply anti-sieze before reinstalling.

 

But don't sand it too much..

 

The fit of the damper pulley to the hub is classified as a light location fit ... oil or anti-seize will help, but the diameter of the parts should not be changed by sanding or any other treatment. Since both parts are CI, corrosion should not be too much of an issue, but since the pulley sits under the water pump, and some folks drive in the winter ... corrosion can occur.

If the damper pulley is really stubborn, you might have to resort to heating the hub assembly ... and that will probably take a lot of heat given the mass of the components. And if you do have to use heat, look to changing the crank, opti and waterpump seals + the harmonic damper.

ATG

 

Just realized that I showed the HF 2-jaw puller sets in the first image above, and then showed how the 8" puller leg could be used ...

I was in HF today, and saw that the 3-piece 2-jaw puller set doe NOT have an 8" long puller ... I have a mixture of 2- and 3-jaw pullers, and the 8" leg is installed on the larger of the 3-jaw HF pullers. The legs are pretty much interchangeable between the 2- and the 3-jaw tools since they all will take a 3/8 securing bolt.

Apologies for any confusion caused!

 

another example of "better is the enemy of good enough". Use an ~18" long piece of 2x2. Place the 2x2 against the balancer and tap it with a rubber mallet. You may have to rotate the balancer in order to tap around the perimeter vs in one place. A socket and ratchet easily reaches the hub bolt while under the car such that you can rotate the engine. Typically takes 5-10 minutes to tap it off.

When Mike says "sand off the rust", he's not talking about taking a grinding wheel and removing an 1/8" of material around the diameter of the hub. He's talking about removing a thousandth or two of surface rust. A scotch-brite pad followed by a light coat of anti-sieze works great for this and the balancer will come off easily the next time. SOP on LT1/4 cars since the first LT1s arrived on the scene in 1992.

Do NOT use heat on the balancer. It has a rubber ring that will be destroyed by heat as you pointed out.

In 20+ years, I have yet to come across a person or situation myself where patience and tapping the LT1/4 balancer from behind didn't work. Do some take more than 5 minutes for the rookies? Yes. However, most are 5-10 minute jobs and the worst ones are 30-45 minutes for those that are mechanically inclined.

 

I buy GM work best for me..I have put MSP cap on some of them ..Had a New GM cap crak after 2,000 miles GM gave me a new one YEA I had to take it off not so good...

 

Horses for courses ... pick the method that works best for you!

Having seen how easy it is to remove the damper with a 2-jaw puller, at my age, I'll pass on jacking the car up, clambering underneath and maneuvering a piece of wood and hammer even if it was only for 5-minutes (and in my case, I tried for an hour!).