Hi guys, I was changing my belts when I noticed that my lower pulley was wiggling. Crawled under and noticed that one of the bolts was missing and that the harmonic balancer would wiggle. Moves front to back about 1/4 inch or so and will spin freely for about 1/3 a turn. The big bolt in the middle is tight. I have noticed that the fan belts have been shaking and the motor is shaking also. Does this mean I need to replace the harmonic balancer? Or is the wiggle and spin normal? Thanks, Jeff Oh Yea, 455
You're kidding, right???? If it moves like that do not drive the car until you investigate further. The harmonic balancer should be rock solid on the crankshaft. If it is rotating a 1/3 of a turn the keyway is wiped out or the outer ring is coming off (depends where you garb to turn) It should not move unless the crank moves with it as well. The bolt might be tight but it sounds like it is not holding anything, perhaps it is seized or shanked out or the balancer is coming apart in the middle. later Tim
Unfortunaltly I am not kidding. I got it about a month ago and noticed the belts wiggling. I thought they were just bad. How do you change the balancer on the car? Also, can you just buy one or do they need to be balanced for individal engines.
As he said, I wouldn't drive the car or even have it running unless you really want a "ram-air hood" Cuz when that thing comes off it could really put a pretty good size air inlet into your hood.
This may be stupid but just to be sure. I am talking about the round disk, inch or so thick and around 7 or so inches diameter. The lower pulleys bolt into. That is the harmonic balancer correct. Also, is there a difference between years of balancers on 455's?
Yup, that sounds like it, lower pulley bolts to it with six small bolts and the balancer itself is held on with one huge bolt in the center, head is 1 1/8" I believe. The balancers are all supposed to balanced for a particular engine. 70-76 will all exchange in a pinch. If you look at them form the fornt with the pulley off, there are holes used for balancing, they get filled as needed. many engines have been put together without being balanced though, but you do not want that thing 1/3 of a turn out. it is designed to dampenthe impulses of the crank and it need so tbe in a certian position to do that. there is a keyway tht the balancer is slotted for so it will only go in at one position, with a little luck somebody just forgot it and the main bolt came loose. See if you can get that large bolt out. Once you get the balancer off (it will slide off) then you will be able to see any possible damage. Later Tim
1 1/8" socket on the balancer bolt. And you'll need a puller to pull it off the crankshaft nose... unless your lucky and its loose enough to just slide right off. Sometimes they will, sometimes they won't. Check for a key in the crankshaft. And don't even think about using a hammer for ANY REASON!:blast: Lots of places will carry the balancer if you need one, and it sounds like you do. Make sure the factory weights from the old balancer go back in the new balancer in the same spot they were. Hope this helps ya!
Balancer OFF OK, I have removed the balancer and it looks to be new. The thing has a 1" grove that narrows on the end to 1/4" or so. The problem apears to be that the balancer was installed and it was not pushed all the way in so that the final part of the grove can grab the crank key and hold it tight. I have looked to slide it back all the way and it is not going on all the way. How do I get the balancer all the way on? Thanks for everyone's help so far.
I assume you mean by 'thing" that the harmonic balancer has the slot that widens on it??? How tight was the bolt? Is there a keyway on the crank? is it in good shape (square?). Get a good flashlight and check out the crank snout,make sure it is not damaged. I have attached a picture to show what a good balancer looks like. If your groove is all messed up, you need to replace it or risk big damage. later tim
Not so good Well on closer look it is busted. See picture. I looked at the crank and the key looks square but looks like the balancer rubbed the end some. Hey Tim, how much for that nice one in the picture? Also, mine does not seem to have any weights installed in it.
OUCH!!! Dude you were close to disaster there.... The one I have really isn't for sale, even with a smoking price by the time you paid shipping from here for that heavy thing you would be hurtin!!LOL AND you are on the opposite corner of the continent which only makes it worse. Should be able to find one locally without too much trouble, take a look around and see what happens. I'm glad you found that before it wrecked your crank, or your car. You spin that sucker to 5000 rpm and let it off and the energy there is amazing... Later Tim
Thanks Well I think I know what to do now. Thanks for the help. Hey Tim, I didn't notice you were that far north. Thanks for the picture and help. The picture showed me mine was trashed.
I can tell you what happens when a balancer comes off. About 22 years ago I was driving down on a backroad in Lousiana and BAM!!! off went the balancer! It put a good size bulge in my cowl induction hood. Also the car had plastic inner fender wells and cracked both of too. Not to mention the horrible shake the engine had right before it died. The car of course went home on a flatbed wrecker. It was a costly repair for the car and engine. Good thing the balancer didn't go thru the hood and into the windshield! I never was sure what happened exactly. The crank broke right behind the#1 journal so I don't know whether the crank broke and then it threw the balancer off or if the balancer came off and the crank broke right after that. It was a bummer!!! Brian
Dang Brian, I am glad I caught it before that happened. This morning I changed my plug wires and took it to a little high RPM test afterwards. I feel pretty lucky it didn't let go then.
www.taperformance.com They have the balancer but not too cheap. If no luck at the junk yard at least you know you can get one. Also when you put a new one on the center bolt should be torqued at 200ft lbs.
You are lucky Jeff! The more I think back to my disaster, I remember now that the engine locked up right after the balancer let loose and I had my hand on the 4 speed shifter and popped it out of gear. The rear tires had locked up when the crank blew and the car was starting to skid. You can't imagine the look on my face when i opened that hood and saw the balancer laying on top of the battery and the crank snout sticking up thru the timing cover!( the fan shroud didn't survive either) After disassembly the I saw that most of the front of the block under the timing cover was gone. There was not anything reusable from the inside of that engine! By the way it was a 71 SS454 Chevelle. I had owned that car since it was 6 years old. But I repaired it and that was that. Brian
Click on this link http://www.v8buick.com/showthread.php?s=&postid=191735#post191735 then scroll down to picture of harm. dampner..........Rick
Balancer Hi Rick, I considered that one and a new reproduction from TA. I ended up ordering a rebuilt one from Poston. My engine is pretty stock with forged 9.25 CR pistons and KB C118 cam. I think the stock rebuild will probably do me. Hope so anyway. JP
Hey Jeff, I just want you to know that stock-style harmonic balancers are tuned to reduce bad harmonics only in a small RPM range. I think after about 4,000 RPM, they don't work anymore! Something to keep in mind if you see any track timeo No:
