Follow Up 1961 harmonic Balancer Question

[Joel T.]

I posted yesterday regarding my harmonic balancer... it fell off my 1961 283/245 while driving. If you guys could help me, I have a couple of follow up questions.

If I look at the balancer which fell off, it appears to be original with no part number stamped on it anywhere. I can see where it was originally "pounded" into place based upon the hammer blow marks which are under the pulley.

1) Given that this one has come off, do I need to replace it with a new/rebuilt one, or can I just clean it up and put it back? The outer disc is chewed up a bit from bouncing along the roadway but the center spindle is fine.

2) What is the procedure to install a new balancer and can I do this with the motor in the car? (If I remove the fan I think I will have some room to gently swing a hammer, but want to check anyway). Does anyone make a tool for this purpose.. I have a puller already.

Thanks!

Joel

[John D.]

Re: Follow Up 1961 harmonic Balancer Question

Remember the problems a big name catalog owner had with his '59 balancer coming loose. Was in all the mags so no secret. If I was going todrive it a lot I would drill the crank and tap it for 7/16-20 with a graded bolt and use same set up as '62 up. Repro bolt set up readily available. Originals very hard to find. That way you don't see it coming loose and trashing the car and causing serious injuries. Just a personal opinion. Realize no good for judging but problem solved safely. I read Joe L's reply and it was very helpful. But the quality of your part sounds questionable. I wouldn't use it. Look for a better one or bolt yours on. There are fellows that rebuild those also. I used to have a name of fellow but lost it. He's in all the mags also. I am sure the DB members can give you a suggestion. John

[Joel T.]

Re: Follow Up 1961 harmonic Balancer Question

John,

Thanks for the advice... As I mentioned to Joe in a separate e-mail, I was debating whether or not to pull the motor and have it redone anyway, this "event" basically made my mind up for me.

The car has about 89,000 miles on it. Someone did a frame off a bunch of years ago, but I have no idea when. I have had it less than a year myself.

This is the second time this puppy has failed me on the road. A few weeks back the clutch linkage failed... somebody installed a wrong throw out bearing and did it wrong to boot.. The fork would twist when the clutch was depressed.. got so bad that it failed. I had just finished putting it all back together (worked great) when this happened... go figure.

Oh well.. could have been worse.... no damage underneath that I can see.

Regards,

Joel

[Joe L.]

Re: Follow Up 1961 harmonic Balancer Question

Joel-----

I'd need to see a photo of the balancer to, possibly, assess whether it can be re-used or determine if it's an original balancer worth even attempting to re-use. If it's not an original balancer, I would not even consider re-using it.

John's suggestion about installing a crank snout bolt is a good one. However, there are 2 things to keep in mind. First, it's no really practical to install usch a bolt with the engine in the car and the crank installed in the engine. It's a machine shop job. There exists equipment that could do the job with the crank installed in the engine and, possibly, even with the engine installed in the car. However, you're VERY unlikely to be able to obtain the services of such equipemnt. So, you really need to disassemble the engine to do it.

Second point is that cranks which had the balancer bolt tapping were generally different forgings/castings than those without the bolt. However, no original bolt cranks can be carefully drilled and tapped for the bolt (by a machine shop).

If you can get enough room to swing a hammer EFFECTIVELY with the engine installed in the car, you should be able to install the balancer without the need for engine removal. A puller can be used to remove the balancer on an engine without a crank snout tapping (unless the balancer "self-removes" as in your situation in which case no removal is necessary). However, there is no tool that I am aware of available for field installation of the balancer for non-bolt cranks. As I mentioned previously, though, you should never apply impactive force (i.e. "pound") directly on the face of the balancer hub (as someone, apparently, previously did in this case). You should install a plate on the face of the balancer which distributes the impactive force over the entire face of the balancer hub without applying ANY force to the balancer outre ring. You can fabricate such a plate form 1/4" or thicker steel stock and use the pulley bolt holes to retain it to the balancer hub.

[Joel T.]

Re: Follow Up 1961 harmonic Balancer Question

Joe,

Thanks again. I will be traveling the next few days but when I get back I will take some photos to show you the condition of the original balancer. I did also order one form Corvette Paragon, hopefully it will be here by week's end too.

Looking the car over again yesterday afternoon, I think I might be able to pull the radiator (gotta check the manuals first) and the fan/pulley to get some good swing room. The only wrinkle I can see is the bar which runs in front of the radiator.. that might be a problem.

Strangely enough I did find a guy on the net who made a tool for himself to install these babys.. 1" steel plate which he bolted to the front of the engine some how and then used his removal tool to press the new one in place. I found it once with Google, did not print it out and cannot find it again.. interesting concept to say the least.

I'll keep you posted...

Regards,

Joel

[Mike B.]

Re: Follow Up 1961 harmonic Balancer Question

Joel,

I also have a '61 with an iffy original balancer. When I undertook to rebuild the engine last winter I could virtually pull it off by hand. I can't imagine how clearance could grow between the crank snout and ID of the balancer (except for a wobble) but I was too leary to reuse it. For extra insurance I had the snout drilled and tapped when the crank was at the machine shop. It was not expensive to do and it provides loads of extra piece of mind. And when/if you want to have the car judged simply remove the bolt and with a shot of touch up paint on the pulley face, no one could ever tell.

Another benefit of tapping the crank is that there is a specific tool made to press the balancer back on which first threads into the snout. I have the tool and since I live in your neck of the woods in NJ, reach out when you are ready and I will be more than happy to provide the tool and the service. Even without the correct tool it is easy as you can simply use the crank bolt (or one a bit longer) to pull the balancer into place. I'm not sure why they were not drilled back when but drilling and bolting sure was a good improvement.

Mike

[Joe L.]

Re: Follow Up 1961 harmonic Balancer Question

Joel-----

I could see where it would be possible to construct a tool for installation of balancers on non-bolt type cranks. Such a tool could be fabricated from steel and use the front motor mount bolt tappings (unused on all Corvettes and 58+ passenger cars) as an anchor point to the block. It would need to be made from stout steel and be well reinforced to avoid distortion, but it could be done. However, I know of no commercially available tool of this sort. The chances are, even if it existed commercially, it would be expensive and really practical only for someone that did this sort of installation on a frequent basis.

Of course, one could fabricate such a tool themselves. But, the effort involved and the expense for the materials might not justify the ultimate utility. Folks have been installing these balancers for years using "impactive force". When the proper procedures and precautions (such as I have previously described) are undertaken, there's uusually no problem.

[Joel T.]

Re: Follow Up 1961 harmonic Balancer Question

Hi Mike, thanks for the post... Another New Jersey guy, perhaps you know route 22 out in Hunterton County where this puppy let loose.

I have the tool which you mentioned for the tapped snout crank, used it on my 1963 just a while ago, thanks for the offer, it is much appreciated. I agree with your comment about not including a bolt way back when... what could they have been thinking about? When my balancer fell off I figured that the bolt must have come loose, fallen out which let the balancer separate. When I got the car home I checked the pulley over and no sign of a bolt ever being there! I tell my wife that some bozo forgot to put the bolt in when they redid the motor years ago. Boy was I wrong!! Thank goodness for this forum!! I always get great advice here!

My plan for this car was to re-do the motor and build it up to be 270+ HP. A buddy of mine is helping with the project which calls for cutting down and re-weighting a crank from a 327 (they have done this before with very good results). If we do this, the issue will take care of itself I think. I have the block in hand but am waiting on the crank a set of heads. I was not going to start this project until the winter sometime (so that I could save up some $$) but now that I have this situation I might just start pulling the whole thing apart.. that is if I cannot figure out how to get the new balancer installed with the engine in the car. If you have the itch to help pull a motor, let me know!!

Regards,

Joel

[Theodore K.]

Re: Follow Up 1961 harmonic Balancer Question

Joel,
Read your two strings with great interest. Same thing happened to me with my 1957 270 hp a few years ago during a trip to Idaho and Canada. Had to get towed in. Luckily found a shop that could get a used one over in Washington State. My old one cracked in the keyway. Would just slide on and off. Difficult to see but it was there.

Replacement had an uncommon problem. The bolt holes in the HB were not tapped quite deep enough. We thought the pulley was tight but instead the bolt bottomed out. Only a few thousandths off. Consequently pulley moved and eventually sheared off the bolts. Of course this was on a mountain Pass in southern Canada. Had to get it towed again. Rented a car, drove down and got my truck and trailer and took it home. Got a third HB and it has been fine for several years.

To get a good hammer swing on the HB, I pulled the radiator, put a wooden baseball bat through the grille and drove it on using a small sledge. If you change it, do not forget to put a new seal in the cover. Also, if a used HB, check the HB shaft for wear and install one of the sleeves available from parts stores to give a smooth sealing surface. Works good.

Of course drill and tapping the crank is best, but considering that this failure is rare, another HB might be worth the trouble rather than a pull and teardown.

Whatever you do good luck.

[Joel T.]

Re: Follow Up 1961 harmonic Balancer Question

Hi,

I thought about the radiator removal but honestly did not think about the baseball bat, great idea.

The other thought I had was a small block of wood and an air hammer, up close.

Joel

[Mike B.]

Re: Follow Up 1961 harmonic Balancer Question

Joel,

I live in Hunterdon County (Stanton in Readington township). I know Route 22 all too well.

I'm willing to help you pull the engine as I am just about out of projects at the moment! But putting it back in with the tranny attached is really where you'll need the help. There are a few hairy moments when that assembly dangles over the car nose that are not for the faint of heart. Send me a private email when you are ready and I'll schedule some time for you.

Mike