Harmonic balancer removal / install on '63

Hi Jason and members, great to see the site is still so popular and so many great cars around. Could you help me with a problem? Does anyone know the size of the bolt needed to thread into the crankshaft to install the harmonic balancer? This is for a '63 with the 390 ci. The manual says use a bolt from a '62 but no size specified. I know I will need an installer tool, just need to get one with the right adapter. Assuming I can get the balancer off to start with of course which is causing some problems at the moment. Any help appreciated. Many thanks, Rich 


Per shop manual and as you noted you need to use the 59 to 62 front harmonic balancer bolt and washer to install the 63 & 64 harmonic balancers. 

The bolt size is  9/16" - 18  and usually about 1 5/8" long...with a very thick large washer. You need the puller tool to get it off but just the large thick bolt and washer to put it back on. This bolt size is usually not one stocked in your typical hardware store but I have a stock of new yellow zink plated Grade-8  9/16" - 18 steel bolts that I sell for $5. If interested shoot me an email to jasonedge@nc.rr.com   

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Comment by Tony and Ginny 429 on November 6, 2018 at 2:34pm

You can leave the bolt in as cadillac did in many years before

I think this is an attemp to save a few pennys on a lot of cars which does seem odd considering all the quality that went into building these yesr cars

Enjoy- or your doing it Wrong !
Comment by Anders on November 6, 2018 at 1:50pm

Would there be a reason not to leave the bolt in the crankshaft?

Comment by Tony and Ginny 429 on September 10, 2016 at 8:23pm
One of the front bumper bolts will work to install the balancer
You may need a few large washers
Comment by Jason Edge on September 10, 2016 at 6:03pm

Russ, I was answering Denny's Question "but what size are the 6 bolts for the pulley ?". I also have the correct installation bolt new for $5 + s/h.

Comment by Russ Austin on September 10, 2016 at 5:16pm

If you get a harmonic balancer removal/installer kit, it will come with the correct size to thread into the crank end.

Comment by Russ Austin on September 10, 2016 at 5:15pm

Richard needs the bolt that goes into the end of the crank, so he can torque down the balancer.

Comment by Jason Edge on September 10, 2016 at 2:48pm

Denny, Per last entry on page 9-42 the pulley to harmonic balancer bolts are 5/16"-18 bolts. What is not listed is the bolt length which is 5/8" and use a standard 5/16" split/spring lock washer. If  you need any of these bolts I have a bin full cleaned harmonic balancer bolts and can put a set of 6 bolts & washers together for say $3 + s/h.

Comment by Denny Link on September 10, 2016 at 2:13pm

but what size are the 6 bolts for the pulley ? thank yoiu

Comment by Russ Austin on September 2, 2016 at 8:51am

Glad you found it, as I forgot to look for the part info. I just tap it into place, with Loc Tite. or Permatex threadlocker.   Freezing the balancer is a good idea, but I would worry about heating the sleeve.

Comment by Eric Pastrama on September 1, 2016 at 11:53pm
I got the sleeve what the best way to get it on ?? Freeze balancer and heat sleeve??


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