Hi I have a 62 dodge custom 880. It looks like the harmonic balance is moving forward and backward on the crank. It makes a clunk as it goes back and forth. How do I fix/tighten the balance up? What I am seeing move is a pulley sized part with with no belt grove in it and it is located between the pulley and the crank case. Zombilly
Would that allow the balance to spin at a slower speed than the shaft is spinning? And how problematic is this? Its been like this for 2 years and no problems yet just the next thing in line for me to fix, you know what I mean.
When it flies apart it will take the radiator , fan and damage the hood . I seen it happpen, don't take any chances with it . Replace it asap!
It might be a good idea to replace this thing asap. Once the inner and outer rings separate there's a real danger of the outer ring breaking and coming apart. As you can imagine, this would create a real shitstorm under the hood.
I've seen them come apart before. One guy had one chunk on a '64 Belair and kept driving it! I gave him one I had laying around and helped him fix it. The only damage was a big dent on the hood. I would also recommend parking it until you get a new one. Hope the crank snout is ok. Bob
Zombilly, I am not questioning what you are seeing, but the "clunk" has me thinking. Are you sure the whole crankshaft is not moving foward and backwards. This would be a severe worn thrust bearing condition, allowing the crank to move back and forth or forward and reverse, in the main housing bores. Believe me, in the 70's, I had a 440 that did the same thing, when I first noticed it during timing with the light, I couldn't believe my eyes. Before you go any further, pull the dampner, and see if the others are correct, and the ring or pulley is just seperating from the hub. If it is the thrust bearing, there is only one repair. R&R, before it destoys the block main webbing and crank. Best of luck, I hope its just the damper.
Like Bulldog said the crankshaft thrust could be worn beyond beleif. The 289 ford clutch pedel would go in and out w/change in rpm.
You might be able to carefully pry foward and backward on the crank pulley, to help diagnose whether its the damper or the crank thrust bearing. The engine wont be running of course, and the tranny should be in neutral if its a stick. A pair of vice-grips and a piece of coat hanger, and you can rig up like a machinist pointer, and see if just the pulley/damper is moving back and forth, or try and get the pointer to the center of the crank bolt/snout and see if the whole crank is moving back and forth on the thrust. Heck, just watching it close with the engine running and a timing light hooked up, might show you exactly whats going on down there. Racing the engine up, and then idling down will cause the crank to "walk" in and out if its the thrust.
I have also seen the thrust washer be a problem as bulldog explained. one more thing to check is the key way on the pulley and crank. if the pulley was loose for some time it is possible for the key way open up and then the pulley will rock back and forth.
So, the balancer/dampener is doing the Hoakie Pokie! I'm not to familiar with MOPARS, but they probably have a bolt that retains the balancer/dampener. If the elastomer "rubber" has broken down, and the parts are separating because of that, you need a new or rebuilt balancer/dampener (they do actually rebuild these things). Like the others have already said, if it comes off, or completely apart, it's going to wreck havock on everything. Butch/56sedandelivery.
I've seen both problems. If just the outer balancer is moving, then it needs a new balancer right away. But if the whole thing moves, along with the crank bolt, then the main thrust bearing is worn. I've seen a crank move for a while a keep on running
If the problem is a worn thrust bearing, the thing may go for a long time. It'll never keep a timing chain in good shape, but it will run. Small block Chryslers have had the issue from the beginning till the last magnums and 3.9 V6 engines were built. One of my Dakotas went over 100K after it recieved a new timing chain when I noticed the problem. personally, I think that is the problem with many SBD performance issues. The spec is less than .003" but they have been measured at nearly 1/8".
The balance can be moved back and forth by hand + or - 1/8" and the crank doesn't move back and forth with the engine running whatsoever . I also noticed that there is some miner rotation play also, about + or - 1/32 on the shaft. So I'm thinking what "Borntoloze" said made sense, although I'm not sure how if the damper has separated from its center tube, then why doesn't the damper spin freely by hand? Well thanks to everyone for their input its been a big help.
Yup its just the outer ring that moves front to back (that makes the noise), but there is some key slop, about 3/32 in the clock or counterclockwise directions. I'm wondering if anyone has tried to mend their balancer before. For instance if there were no rubber pieces missing and they were, eh-um, low on cash, if epoxying both sides of where the inner and the outer ring come together would hold till they could get there hands on a new one. Not from the hamb of course, but a-a a guy from another board.
Haven't tried and I wouldn't. It would be compromising the purpose of the rubber in there to begin with. When it decides to let loose there will be no stoping it, no second chances.......... I'd find another way to save the needed bucks for a proper repair even if it meant giving up barley pops for awhile, serious deal in my book. Ed
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