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Harmonic Balancer Install Disaster

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Old May 26, 2019 | 11:27 PM
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Default Harmonic Balancer Install Disaster

Well... I didn't realize I needed to get the ID of my ATI harmonic balancer honed to size and tried to install it with an Oreilley's rental harmonic balancer installer...

Now the shaft of the tool broke off and I can get neither it, nor the balancer off. I've been recommended not to try to get the balancer off until I can get the tool shaft off or I'll potentially strip the threads in the crank.
I can't get a normal locking vice grip on the end of the stud because the harmonic balancer is blocking it. I picked up a needle nose vice grip and it doesn't grasp enough to remove the stud...

Based upon the ATI Installation instructions, my understanding is that for my stock GM Forged Crank I need the ID of the balancer honed to 1.2453" +/-0.0001, once I actually figure out how to get it off again...


Video of current state: https://www.facebook.com/adamindublin/videos/10157567478421929/




Adam

Last edited by NewbVetteGuy; May 26, 2019 at 11:30 PM.
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Old May 26, 2019 | 11:42 PM
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you can likely get the balancer off with a 3 jaw gear puller. I have one I use and it has 3 10 in long jaws. Then maybe you can get something on the broken bolt to remove
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Old May 27, 2019 | 12:03 AM
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Originally Posted by henrikse
you can likely get the balancer off with a 3 jaw gear puller. I have one I use and it has 3 10 in long jaws. Then maybe you can get something on the broken bolt to remove
I agree with getting the balancer off first. But i wouldn't use anything that will press against the broken bolt. try to get something to cover the bolt and press against the shaft.
If the balancer is on tight enough you may need to try a hydraulic puller. Hopefully you don't need to go to a "hot spanner"

The warning sign that something wasn't right was when you had to go to the 18" wrench and again when the engine was turning over. But I bet you'll never make this mistake again.
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Old May 27, 2019 | 12:03 AM
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I think something happened like this on an episode of fast and loud with an old GT 500 they got in. They used some JB Weld and a piece of metal to make an extension to grab on to.
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Old May 27, 2019 | 01:38 AM
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Yep...ATI's almost always need honed. It's in the instructions.

Get balancer back off first. Maybe stick a socket or piece of pipe inside balancer/over bolt and up against crank so you can put a puller up against it. It needs to be long enough to extend past bolt. Might have to slip a piece of steel in there for it to push against. My puller has a flat adapter for the end that can replace the pointed one.

Good luck.

JIM
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Old May 27, 2019 | 06:45 AM
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The threaded end MAY come out of the crank pretty easy. I snapped one off in a Honda and it spun right out with hammer and punch. Bolt, not puller end. Try a reverse drill bit. First, drill into the rest of the puller shaft to see how hard it is. It is also possible the threads galled together and it is gonna be a machine shop job to re-thread the crank snout. A 3 jaw puller may well pull the outside of balancer off leaving the hub there. Then grab the hub with same 3 jaw and pull the rest. Send both pieces back to J C Whitney and get an OEM balancer. I love the way the aftermarket sells new parts that you have to have machined to correct size.

Last edited by derekderek; May 27, 2019 at 06:48 AM.
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Old May 27, 2019 | 07:30 AM
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To add to what Derek said: I'd remove the balancer off of the hub. It's held on with 9 bolts. Well, maybe 6 since it looks like you removed the 3 larger ones already. Use a Torx Plus socket. DO NOT use a regular Torx socket. The broken bolt should not be bound in the crank unless you bottomed it out and should turn out using a punch and hammer to turn it out. I've had to hone out some ATI balancer while some needed to sit on a hot plate, and others pressed on with no issues. Did the bolt break below the surface of the crank? If so, get a piece of bar stock to use for the puller pressure screw to bear against as not to go near the threads. Inspect the crank snout closely for any displaced metal. either way, I would get a new hub.
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Old May 27, 2019 | 11:45 AM
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I used my tool that looks like this to pull the harmonic balancer off the SBC 400 project I am working on.
https://shop.advanceautoparts.com/p/...B&gclsrc=aw.ds
A good shot of PB blaster from both sides helped.
To keep the crank from turning I just used some bolts in the flywheel end of the crank and a socket breaker bar braced between 2 of the bolts.
Like others pointed out....use a socket turned upside down that just fits inside the balancer to push against so not to damage what is left of the bolt.
Depending upon what you find is left of the installer bolt, you may luck out and just back it out.
Good luck.
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Old May 27, 2019 | 05:02 PM
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The balancer installer has individual crank-specific aluminum pieces that install into the crank, then the long bolt screws into that so even if the bolt breaks-off it doesn't get broken off in the crank and screw up the crank (honestly I think it's just so one kit works on most all engines and that's a side-effect).

I drilled the end of the hardened shaft and used EZ Outs to get the shaft out. (I didn't know that I could remove the balancer at this point.)

Then removed the harmonic balancer with a rental puller, bought a replacement bolt for the installer and took both back.
Had troubles getting the insert out that went into the end of the crank but I tighted a regular locking vice grip AND my needle nosed locking vice grip on it at the same time and could unscrew it with the two fo them.

Balancer will be going to the machine shop to get honed to size tomorrow or Wednesday and I'll try again.
Disaster (maybe narrowly) averted!


Thank (AGAIN) all!

Adam
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Old May 27, 2019 | 05:05 PM
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Originally Posted by 427Hotrod
Yep...ATI's almost always need honed. It's in the instructions.
JIM
It sure was. I bought this second hand and didn't get the instructions, but ti's definitely in the online instructions.
I was so close to being done I didn't stop to read directions on this one and got "bit".
Unfortuantely the YouTube video I watched for the procedure showed a guy using a huge crescent wrench so when it got tough, I assumed that's how it was SUPPOSED to go...


Adam

Last edited by NewbVetteGuy; May 27, 2019 at 05:10 PM.
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Old May 27, 2019 | 07:12 PM
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Originally Posted by NewbVetteGuy
The balancer installer has individual crank-specific aluminum pieces that install into the crank, then the long bolt screws into that so even if the bolt breaks-off it doesn't get broken off in the crank and screw up the crank (honestly I think it's just so one kit works on most all engines and that's a side-effect).

I drilled the end of the hardened shaft and used EZ Outs to get the shaft out. (I didn't know that I could remove the balancer at this point.)

Then removed the harmonic balancer with a rental puller, bought a replacement bolt for the installer and took both back.
Had troubles getting the insert out that went into the end of the crank but I tighted a regular locking vice grip AND my needle nosed locking vice grip on it at the same time and could unscrew it with the two fo them.

Balancer will be going to the machine shop to get honed to size tomorrow or Wednesday and I'll try again.
Disaster (maybe narrowly) averted!


Thank (AGAIN) all!

Adam
Hi Adam, the shop is going to need the very EXACT dimension (exact as in measured with a 1"-2" micrometer) on the crank snout or you may never hit the required press fit!

Thanks, Gary in N.Y.

P.S. On a side note we install almost all our balancers using hot oil, they can be installed all the way on (with the SBC's) by hand with a pair of gloves. Occasionally the BBC's need a little extra help (a good installer) to get them seated! The press fit is critical, you are working with "tenths", not "thousandths"!

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Old May 27, 2019 | 07:35 PM
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The balancer hole should be .002 to .001 smaller than the the crank. Then you heat the balancer up to maybe 250* in the oven. Make sure the end of the crank has a slight bevel on it’s circumference vs a sharp edge. Use sand paper or whatever you got to make it smooth.
once the balancer is hot, you must act quickly to install it before it cools or the heat transfers to the crank. Ya you’ll need gloves.

i did mine early in the morning so the crank was as cool as it could be And sprayed a little carb cleaner on it to cool it via evaporation. This makes the diameter of the crank as small as you can.

i also use a little light oil on the crank to prevent galling. If I recall it was a penetrating oil from a spray can, it’s very thin.
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Old May 27, 2019 | 07:53 PM
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Not thousandth's ... Not 0.001" but about 0.0001" or even 0.00005" smaller
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Old May 28, 2019 | 10:50 AM
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Originally Posted by jackson
Not thousandth's ... Not 0.001" but about 0.0001" or even 0.00005" smaller
Well that sounds a little loose to me. Over time the vibration of the engine (harmonics) may egg the hole out if it's not a good enough interference fit. Mine was at .0015" and it went on with it heated pretty well. Cold you may not have any success or it may gall the inside of the dampner. If a guy is really concerned I guess you could shoot for the low side and maybe put it on at .0008" interference or thereabouts.
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Old May 28, 2019 | 11:13 AM
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Originally Posted by REELAV8R
Well that sounds a little loose to me. Over time the vibration of the engine (harmonics) may egg the hole out if it's not a good enough interference fit. Mine was at .0015" and it went on with it heated pretty well. Cold you may not have any success or it may gall the inside of the dampner. If a guy is really concerned I guess you could shoot for the low side and maybe put it on at .0008" interference or thereabouts.
This is pretty much right on the money. Anywhere between .0008" and .001" is good on most balancers. You definitely don't want .002", I also wouldn't put .0015" either unless it is a "cast-hub" piece (most OEM), steel hubs like the above numbers.

Thanks, Gary in N.Y.

P.S. Working with these dimensions requires some decent tools (mikes/bore gauges), same as when measuring pin-to-piston or pin-to rod numbers, you need to be very accurate for the most part! I also wouldn't recommend heating the entire balancer to make it a temporary slip-fit, only the hub needs heating?
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Old May 28, 2019 | 11:26 AM
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My numbers are too tight.

sbc --- Ati reads fit the bore of Their sbc hub ID 0.0009" to 0.0012" Smaller (interference) than sbc crank OD.

BBC --- Ati reads fit the bore of Their BBC hub ID 0.0007" to 0.0009" Smaller (interference) than BBC crank OD.
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Old May 28, 2019 | 11:31 AM
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My thought on heating the entire balancer is that it’s exposed to no less than 180* each time you drive and maybe as much as 230* ( depending on how hot your engine runs) and it may see even higher temps after shut down, so 250* should do no harm to the rubber compound in the dampener.

Last edited by REELAV8R; May 28, 2019 at 11:34 AM.
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Old May 28, 2019 | 12:11 PM
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Thanks all.

I've got a set of what I'm pretty sure are Chinese OD micrometers (I checked each of them against the included standards and they're dead-nuts accurate according to that anyway)
Amazon Amazon

I'll Mic up the crank in a couple of places tonight (or tomorrow night) in 4 places and see what it reads at.
Machine shop said they'll go 1 thou over whatever the crank reads and I can drop it off tomorrow morning.

I like the hot oil method that Gary posted, but I have a GAS oven so that's pretty terrifying. I'm thinking that I can get a shorter metal can like that and do a much smaller volume in a "double boiler" with boiling water around the oil. I'll make sure to have some fire extinguishers at the ready. (So I should be able to get the hub up to around 200F)

I've also got a 20 lb CO2 tank so I can definitely chill the crank pretty cold right before I go to press it on.
I never would've guessed that the harmonic balancer of all things, would require some of the most precision measuring of anything in the engine assembled. NEVER would've guessed that. #KeepingNewbInMyForumName...



Adam

Last edited by NewbVetteGuy; May 28, 2019 at 12:12 PM.
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Old May 28, 2019 | 12:38 PM
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Gas or electric, no difference, if it makes you more comfortable heat up the oven first then put the balancer in. Water is not a good lubricant. So getting it hot over water may not be ideal.
Gary's method would both heat the hub and lubricate the hole a little from off gassing of the oil.

Last edited by REELAV8R; May 28, 2019 at 12:39 PM.
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Old May 28, 2019 | 01:38 PM
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Originally Posted by REELAV8R
My thought on heating the entire balancer is that it’s exposed to no less than 180* each time you drive and maybe as much as 230* ( depending on how hot your engine runs) and it may see even higher temps after shut down, so 250* should do no harm to the rubber compound in the dampener.

You just want to stay a little conservative with the heat because the hub will be in direct contact with the timing cover seal
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