Harmonic Balancer Question

[vetman]

I just rebuilt the engine on my '68 327/300 and have a problem I've never encountered before (I've succesfully rebuilt 15 small blocks). During disassembly I broke two pullers removing the harmonic balancer, but finally got it. I had the crank turned, and after re-assembly, the harmonic balancer slides right on using a bolt/washer threaded into the end of the crank. However, if I align the crank/waterpump pulleys, I can't bottom the balancer against the crank snout. I'm afraid to leave it in that position... in case it decides to come loose. Any thoughts as to why I had so much trouble removing it or how I should ensure it stays put after start-up? Is it possible it had the wrong balancer to begin with (don't know the history of the car) and is there a casting number I should check for?

[LLC5]

How about the wrong water pump. Didn't they have a long and short nose pump? Just a guess.

[vetman]

The water pump is the short style and has the correct casting number for the '68 model year...

Hello
Water pump hubs can be moved on or off a little to help the alignment.
You did not indicate how much is was off. 1/4 inch or less this can be the solution. Remove the backing plate and press directly on the shaft to move it in. Use a puller to move it out. Best of luck
Rick

I forgot to mention that the early Vettes had a spacer behind the balancer to compensate for the motor mount between the water pump and the block. You could have a spacer machined the correct width an insert behind the balancer. May also require a notch for the keyway. Nothing fancy here one could do the clearancing with a file if needed. I would not leave it loose under any circumstances. I know GM did not use bolts on lost of SBC but even they decided it was bad practice.

[aquaholic]

are you sure you are using the right bolt to put the ballancer back on? maybe the bolt is just a little to long and is bottoming out in the blind female crank hole before it pulls the ballancer tight. iv'e rebuilt a bunch also but its been a long long time. i do not remember shims or spacers on any of them though. nor have i ever had to adjust a water pump shaft length to get a pulley to line up.

[vetman]

Actually, I have the opposite problem. The bolt I'm using will allow me to pull the balancer too far in. Then the crank pulley WILL NOT line up with the water pump pulley. The difference is about a half inch. So, to get the pulleys in the right place I need to move the balancer out a bit, but don't know how to secure it there. The fact that I broke two pullers taking it off tells me the last guy had the same problem and must have used some type of adhesive to hold it in place. I've never had this type of problem before...just wanted to see if anyone else has??

[ToolGuy]

The pullers should not have broke. At least the kind we make and sell can take a major beating. Something indeed is just not right here...

[aquaholic]

i feel your pain. 1/2 inch is way further than i thought we were talking about here. thats a major amount of space. the only thing that i could recommend is an NOS balancer from paragon. they aren't cheap at about $150 but what are the real choices here. i could also double check your water pump number for you if you list it just for a double verification. i believe its safe to assume the water pump pulley isn't on backwards also since that would make the gap about 2-3 inches or so. grab a paragon catalog and take a look at the balancers in there. the pictures are good and you might be able to tell something from them. they list 2 for a small block. one is for some special hi perf small block and has fins casted into the motor side and the other without the fins is for everything else (small block that is). the big block one is totally different. you can check their website but i dont know if it has the details that the catalog has. http://www.corvette-paragon.com