Can the harmonic balance come loose?

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May be a stupid question.... but when tightening the bolt how do I keep the crank from turning?
I'll be playing with this when I get off of work later.

Thanks!
 
Remove the starter and wedge a screw driver in the ring gear teeth.....
 
Well, here we go...

I couldn't keep the crank from turning, however it was on tight enough to turn the engine over obviously.

So I took off the fan, belts ect... and it just seemed weird.
I could move the pulley (still attached to the harmonic balancer up, down, in and out with out hardly any effort at all about 1/8" I would think (although I could be wrong) that the crank would be heavy enough that you wouldn't be able to move it with your fingers? (unless maybe the crank was broke right at the balancer?) but then I wouldn't be able to turn the whole engine over by the crank bolt either.

I guess I'm confused by this? :dontknow:

I made a video with my phone. If you turn up the volume you can hear the noise it makes, and hopefully even though its a dark video you can see how easy it moves. I'm not as slick as my friend (above) that can make cool .gif files :)

Thanks guys!!

[ame="http://www.youtube.com/watch?v=ATMr_SAbG2c"]Bad bearings? - YouTube[/ame]
 
I had this EXACT thing happen to a 360 I built. I always check the thrust clearance, EXCEPT, on this 360. Just missed it. Turned out the motor was used with some NOS and it killed the crank. My machinist, Dunkums in NN VA, turned the crank and they missed it also. Both sides of the thrust surface on the crank were ground away and the crank would run in and out just like your video. You can not fix it with the bolt. You need a new crank. I ran that 360 for 25K miles before I yanked the engine and put a new bullet in. Your mileage may vary. Sorry Dude.
 
I think you nailed it originally. I think it's the balancer, OR unfortunately, the crankshaft is broken in front of the first throw. It happens and it will keep running because the two pieces wedge together. Remove the balancer and you'll know for sure. I don't think it's the thrust bearing. No way would you be able to move the entire crank that easily with the engine still assembled. Either the balancer is broken, or the snout of the crank. Remove the balancer and you'll know.
 
Well,, I'm sorry to hear it wasn't the bolt,, in which case, like the others said,, you've got serious problems requiring tear down...

I agree with Rusty,, by your description, it sounds like a broken crank .. too bad..

hang in there...
 
How can I take off this balancer? I don't have air tools, Any other methods of keeping the crank from turning?

Thanks.
 
I hate to say it but after 6 years of playing with this thing I think I might be done. Time, money, patience have worn thin.

If I just cut my losses I wonder what I can sell this car for? (broken crank and all :/ )
 
Make sure it's broken first. I've had them fool me before. Balancers DO break. They crack right in the keyway and the crack grows until they loosen up. Can you tell if the balancer moves independently of the crank? Even if you cannot, I would pull the balancer to be damned sure......before you give slam up.
 
I've seen this happen on a 350 chevy that came into the shop. Same symptoms, Found the crank broke under the #1 main cap.
 
Been where you are, I'm sorry to say, - find out what the problem is,, it could be the balancer, I've not seen a broken one, but others have,,

You'll likely need a puller to get balancer off, (if it's cracked as Rusty says, you wont need a puller), some have said you can borrow tools free from Autozone. (deposit required)

You'll not only find knowledge here,, but support as well.. hang in there,, it does get better,,..

Remember the smiles and the miles.. and the **** faced grin after a smoke show.. it'll happen again...
 
A replacement crank and bearings can be had for under 200 bucks. From there, it's all just labor.
 
It was a weird situation when this thing was built too.
I did work for the shop and in return they built the motor. I even remember I saw they installed a Eagle crank, and I said to them, wth? Of course you have to use the cheapest crack out there! But they said they balanced it in the shop before the install so its internally balanced, so everything should be fine... well I guess it was 10,000 mi Fine.

It's a stoker motor too.

I'm afraid if I tear this thing apart I won't be able to stop myself either. They used some stock parts (like the connecting rods) that I'd feel more comfortable if I replaced, one head is milled more then the other, I'd like to fix that too. That's what I mean though, everything just keeps adding up $$$ But you guys know how that all goes.
 
okay well lets get the balancer off first. this is how i would go about it remove the pulley from the ballancer. go to hardware store and get some some bolts that will screw in to ballancer. now that you have these screw two in to ballabcer now take a closed end wrench and put the wrench head over one of the bolts and the other part up against the other screw. now take a socket wrench to the ballancer bolt hold on to wrench and break the bolt loose. i hope this helps
 
not to say been there done that, but the people that put mine to gether striped the bolt that held my on. good luke
 
Seems to me if the front of the crank was broken the oil seal would be leaking badly.
The fact that it doesn't make noise in park then does make noise in drive does suggest the thrust bearing. Thrust bearing wear allows forward back movement but not the up/down side to side movement. That movement requires moving pistons and everything else so it wouldn't be easy to do by hand. Just strange...
I would have to get that balancer off and know its not the problem.
Here's what you can try... Get a impact grade socket and a good long 3/4 pull bar for the balancer bolt. Wedge it in such a way as it cannot move clockwise. Bump the starter. That should break the bolt loose so you can back it out. Pray that the balancer will fall off the crank snout. If it does, you can suspect the bolt was too long and bottomed in the hole. That would allow the bore in the balancer to fail, slowly but surely.
Hope and pray for the best and be prepared for the worst is all any of us can do.
 
Myasylum - I agree with REDFISH, I have installed a balancer bolt which was too long and did not catch it at first. When I did this I used an impact wrench - BIG NO-NO, learned the hard way. Result, needed to re-thread and put in a smaller bolt. Recommendation would be to go to Harbor Freight and buy a low cost balancer puller, about $15, get some anti-seize also. Follow what REDFISH said, but be very careful. Once the bolt is off, find a mic and check the depth on the bolt, bolt should not go all the way to the bottom, threads stop before that and you want the bolt to go about 75% down the threads. If you messed up the thread, you can get a tap from Summit and run it down, with anti-seize. You can probably do all this without pulling the balancer. I used a propane torch to heat the bolt to remove it when mine was on very tight, again watch you seals, anything rubber, overheating the snout etc. When you re-install the the bolt use a lot of anti-seize. I do think this is the issue, if they used an aftermarket crank with the factory bolt and with signs and symptoms you stated and showed, this is from my experience.

If the thrust was the case or something was broken, your signs are subtle. Easy fix, step away, have a coke and enjoy.
 
Also, you could peek inside that sheetmetal transmission cover and see if the flywheel is moving in and out while someone else pushes/pulls the balancer in and out. That would tell if the entire crank is moving together back n forth (thrust bearing) and not just the harmonic sliding on the end of the crank.
 
Get a impact grade socket and a good long 3/4 pull bar for the balancer bolt. Wedge it in such a way as it cannot move clockwise. Bump the starter. That should break the bolt loose so you can back it out. Pray that the balancer will fall off the crank snout..

This is an excellent way to break loose the crank bolt,, but be very careful..

The Breaker bar must be firmly against whatever support you're using,, or the whole wrench assemby could fly off quite violently..

I still hpe it's the damper sliding back and forth...
 
By his video and the ease at which he can move it, he is not moving the whole crank. It's either a broke balancer or broke crank at the number one main
 
Well, here we go...

I couldn't keep the crank from turning, however it was on tight enough to turn the engine over obviously.

Bad bearings? - YouTube

I can't be the only one using vise grips to hold the damper while removing the bolt? vice grips on damper, pressing against front cover. never had any problems.
 
Read if over, things that can cause crank failure.[ame]http://www.scatcrankshafts.com/scattechpdfs/Break_the_Nose.pdf[/ame]

To remove or tighten the crank bolt remove the starter or converter shield and hold the flex plate or converter with a bar, this may take a 2nd set of hands
 
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